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1545 lines
52 KiB
1545 lines
52 KiB
;__VDUDRIVER_______________________________________________________________________________________
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;
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; VDUDRIVER FOR CBIOS 2.2, PAGED.
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;
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; VDU DRIVERS BY: ANDREW LYNCH
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; KEYBOARD DRIVERS BY: DR JAMES MOXHAM
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; REMAINDER WRITTEN BY: DAN WERNER -- 11/7/2009
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;__________________________________________________________________________________________________
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;
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;__________________________________________________________________________________________________
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; DATA CONSTANTS
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;__________________________________________________________________________________________________
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;IDE REGISTER IO PORT ; FUNCTION
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READR .EQU 0F0h ; READ VDU
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WRITR .EQU 0F1h ; WRITE VDU
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SY6545S .EQU 0F2h ; VDU STATUS/REGISTER
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SY6545D .EQU 0F3h ;
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VPPIA .EQU 0F4h ; PPI PORT A
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VPPIB .EQU 0F5h ; PPI PORT B
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VPPIC .EQU 0F6h ; PPI PORT C
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VPPICONT .EQU 0F7h ; PPI CONTROL PORT
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STATE_NORMAL .EQU 00H ; NORMAL TERMINAL OPS
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STATE_ESC .EQU 01H ; ESC MODE
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STATE_DIR_L .EQU 02H ; ESC-Y X *
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STATE_DIR_C .EQU 03H ; ESC-Y * X
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ESC_KEY .EQU 1BH ; ESCAPE CODE
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;
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;__________________________________________________________________________________________________
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; FUNCTION JUMP TABLE
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;__________________________________________________________________________________________________
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;
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VDU_DISPATCH:
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LD A,B ; GET REQUESTED FUNCTION
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AND $0F ; ISOLATE SUB-FUNCTION
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JR Z,VDU_IN
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DEC A
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JR Z,VDU_OUT
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DEC A
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JR Z,VDU_IST
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DEC A
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JR Z,VDU_OST
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CALL PANIC
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;
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VDU_INIT:
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CALL INITVDU
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RET
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;
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VDU_IN:
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CALL GET_KEY
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LD E,A
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RET
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;
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VDU_IST:
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CALL IS_KBHIT
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RET
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;
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VDU_OUT:
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LD C,E
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CALL CHARIN
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RET
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;
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VDU_OST:
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CALL PANIC
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;
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;__________________________________________________________________________________________________
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; INITIALIZATION
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;__________________________________________________________________________________________________
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INITVDU:
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CALL VDUINIT ; INIT VDU
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CALL KB_INITIALIZE ; INIT KB
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; CALL PR_INITIALIZE ; INIT PR
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; CALL DSPMATRIX ; DISPLAY INIT MATRIX SCREEN
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; CALL WAIT_KBHIT ; WAIT FOR A KEYSTROKE
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LD A,0 ; EMPTY KB QUEUE
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LD (KB_QUEUE_PTR),A ;
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CALL PERF_ERASE_EOS ; CLEAR SCREEN
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CALL PERF_CURSOR_HOME ; CURSOR HOME
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RET
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;
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;__CHARIN__________________________________________________________________________________________
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;
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; PROCESS INCOMMING CHARACTER AND DISPLAY ON SCREEN OR PERFORM FUNCTION
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; C: INCOMMING CHARACTER
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;__________________________________________________________________________________________________
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CHARIN:
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LD A,C
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PUSH AF ; STORE AF
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LD A,(TERMSTATE) ; MOVE CURRENT STATE INTO A
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CP STATE_NORMAL ; NORMAL PROCESSING STATE?
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JP Z,CHARIN_NORM ;
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CP STATE_ESC ; ESCAPE PROCESSING STATE?
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JP Z,CHARIN_ESCSTATE ;
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CP STATE_DIR_L ; WAITING FOR Y COORD STATE?
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JP Z,CHARIN_DIR_L_STATE ;
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CP STATE_DIR_C ; WAITING FOR X COORD STATE?
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JP Z,CHARIN_DIR_C_STATE ;
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LD A,STATE_NORMAL ; UNKNOWN STATE, RESET STATE
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LD (TERMSTATE),A ;
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POP AF ;
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RET ;
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;__CHARIN_DIR_L_STATE______________________________________________________________________________
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;
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; PROCESS "WAITING FOR Y COORD STATE"
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;__________________________________________________________________________________________________
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CHARIN_DIR_L_STATE:
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LD A,32 ; MOVE 32 (' ') INTO A
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LD C,A ; PARK INTO C
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POP AF ; GET CHAR FROM STACK
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SUB C ; DECODE CHAR INTO USABLE Y COORD
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CP 24 ; IS OFF SCREEN?
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JP M,CHARIN_DIR_L_STATE_CONT
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LD A,23 ; YES, PLACE CRSR ON LAST ROW
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CHARIN_DIR_L_STATE_CONT:
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LD (TERM_Y),A ; NO, USE DECODED VALUE
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LD A,STATE_DIR_C ; SET UP STATE TO GET X COORD
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LD (TERMSTATE),A ;
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RET
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;__CHARIN_DIR_C_STATE______________________________________________________________________________
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;
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; PROCESS "WAITING FOR X COORD STATE"
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;__________________________________________________________________________________________________
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CHARIN_DIR_C_STATE:
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LD A,32 ; MOVE 32 (' ') INTO A
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LD C,A ; PARK INTO C
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POP AF ; GET CHAR FROM STACK
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SUB C ; DECODE CHAR INTO USABLE X COORD
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CP 80 ; IS OFF SCREEN?
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JP M,CHARIN_DIR_C_STATE_CONT
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LD A,79 ; YES, PLACE CRSR IN LAST COLUMN
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CHARIN_DIR_C_STATE_CONT:
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LD (TERM_X),A ; NO, USE DECODED VALUE
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CALL GOTO_XY ; SET CURSOR POS
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LD A,STATE_NORMAL ; RESET STATE TO NORMAL
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LD (TERMSTATE),A ;
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RET
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;__CHARIN_NORM_____________________________________________________________________________________
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;
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; PROCESS NORMAL STATE
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;__________________________________________________________________________________________________
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CHARIN_NORM:
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POP AF ; GET CHAR FROM STACK
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CP 0AH ; IS LINEFEED?
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JP Z,CHARIN_LF ;
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CP 09H ; IS TAB?
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JP Z,CHARIN_TAB ;
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CP 08H ; IS BS?
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JP Z,CHARIN_BS ;
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CP 0DH ; IS CR?
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JP Z,CHARIN_CR ;
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CP 07H ; IS BELL?
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JP Z,CHARIN_BELL ;
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CP 13H ; IS XOFF?
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JP Z,CHARIN_XOFF ;
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CP 11H ; IS XON?
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JP Z,CHARIN_XON ;
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CP ESC_KEY ; IS ESC?
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JP Z,CHARIN_ESC ;
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JP VDU_PUTCHAR ; NORMAL OUTPUT CHAR
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;__CHARIN_ESC______________________________________________________________________________________
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;
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; PROCESS "ESC" STATE
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;__________________________________________________________________________________________________
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CHARIN_ESC:
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LD A,STATE_ESC ; ESC PRESSED, STATE TO ESCPRESSED
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LD (TERMSTATE),A ;
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RET
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;__CHARIN_LF_______________________________________________________________________________________
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;
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; PROCESS LINE FEED
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;__________________________________________________________________________________________________
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CHARIN_LF:
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LD A,(TERM_Y) ; MOVE CRSR Y COORD INTO A
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INC A ; INC A
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LD (TERM_Y),A ; STORE NEW Y COORD
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JP GOTO_XY ; SET CRSR POSITION
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;__CHARIN_TAB______________________________________________________________________________________
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;
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; PROCESS TABS
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;__________________________________________________________________________________________________
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CHARIN_TAB:
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LD HL,TABSTOPS ; SET HL TO TAB STOP TABLE
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LD A,(TERM_X) ; MOVE CURENT CRSR X COORD INTO A
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INC A ; INC A
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LD C,A ; STORE CRSR X COORD INTO A
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CHARIN_TAB_LOOP:
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LD A,(HL) ; GET NEXT TAB STOP
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OR A ; IS ZERO?
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JP Z,CHARIN_TAB_EXIT ; END OF TABLE, PROCESS 73+
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INC HL ; SET POINTER TO NEXT TABLE ENTRY
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CP C ; IS CURRENT ENTRY > X COORD?
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JP M,CHARIN_TAB_LOOP ; NO, LOOP
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LD (TERM_X),A ; YES, USE IT
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JP GOTO_XY ; SET CRSR POSITION
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CHARIN_TAB_EXIT:
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LD A,(TERM_X) ; COLUMN IS PAST LAST TAB STOP, SET A TO CRSR POS
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CP 79 ; IS LAST PHYSICAL POS?
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RET Z ; YES, DO NOTHING
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INC A ; NO, INC CRSR BY ONE
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LD (TERM_X),A ; STORE NEW X COORD
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JP GOTO_XY ; SET CRSR POSITION
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TABSTOPS:
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.DB 09,17,25,33,41,49,57,65,73,00
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;__CHARIN_BS_______________________________________________________________________________________
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;
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; PROCESS BACKSPACE
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;__________________________________________________________________________________________________
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CHARIN_BS:
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JP PERF_CURSOR_LEFT ; PERFORM CRSR LEFT FUNCTION
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;__CHARIN_CR_______________________________________________________________________________________
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;
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; PROCESS CARRAGE RETURN
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;__________________________________________________________________________________________________
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CHARIN_CR:
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LD A,00H ; MOVE 0 TO X COORD
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LD (TERM_X),A ;
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JP GOTO_XY ; GOTO XY COORDS
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;__CHARIN_BELL_____________________________________________________________________________________
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;
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; PROCESS BELL
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;__________________________________________________________________________________________________
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CHARIN_BELL:
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;
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; NO HARDWARE FOR THIS, DO NOTHING
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;
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RET
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;__CHARIN_XOFF_____________________________________________________________________________________
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;
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; PROCESS XOFF
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;__________________________________________________________________________________________________
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CHARIN_XOFF:
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;
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; SHOULD NOT BE NECESSARY FOR LOCAL IMPLIMENTATION
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;
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RET
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;__CHARIN_XON______________________________________________________________________________________
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;
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; PROCESS XON
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;__________________________________________________________________________________________________
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CHARIN_XON:
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;
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; SHOULD NOT BE NECESSARY FOR LOCAL IMPLIMENTATION
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;
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RET
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;__CHARIN_ESCSTATE_________________________________________________________________________________
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;
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; PROCESS ESC STATE
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;__________________________________________________________________________________________________
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CHARIN_ESCSTATE:
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POP AF ;
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CP 'A' ; IS CURSOR UP?
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JP Z, PERF_CURSOR_UP ;
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CP 'B' ; IS CURSOR DOWN?
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JP Z, PERF_CURSOR_DOWN ;
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CP 'C' ; IS CURSOR RIGHT?
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JP Z, PERF_CURSOR_RIGHT ;
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CP 'D' ; IS CURSOR LEFT?
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JP Z, PERF_CURSOR_LEFT ;
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CP 'F' ; IS ENTER GRAPHICS MODE?
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JP Z, PERF_ENTER_GR ;
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CP 'G' ; IS EXIT GRAPHICS MODE?
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JP Z, PERF_EXIT_GR ;
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CP 'H' ; IS CURSOR HOME?
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JP Z, PERF_CURSOR_HOME ;
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CP 'I' ; IS CURSOR HOME?
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JP Z, PERF_REVERSE_LF ;
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CP 'Y' ; IS REVERSE LINE FEED?
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JP Z, PERF_DIRECT_ADDRESS ;
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CP 'K' ; IS ERASE TO END OF LINE?
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JP Z,PERF_ERASE_EOL ;
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CP 'J' ; IS ERASE TO END OF SCREEN?
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JP Z,PERF_ERASE_EOS ;
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CP 'Z' ; IS TERMINAL IDENTIFY?
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JP Z,PERF_IDENTIFY ;
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CP '{' ; IS ENTER HOLD SCREEN MODE?
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JP Z,PERF_ENTER_HOLD ;
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CP 05CH ; IS EXIT HOLD SCREEN MODE?
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JP Z,PERF_EXIT_HOLD ;
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CP '=' ; IS ENTER ALT KEYPAD MODE?
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JP Z,PERF_ENTER_ALT ;
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CP '}' ; IS EXIT ALT KEYPAD MODE?
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JP Z,PERF_EXIT_ALT ;
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CALL VDU_PUTCHAR ; NORMAL OUTPUT CHAR
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JP SET_STATE_NORMAL ;
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;__PERF_REVERSE_LF_________________________________________________________________________________
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;
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; PERFORM REVERSE LINE FEED
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;__________________________________________________________________________________________________
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PERF_REVERSE_LF:
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CALL SET_STATE_NORMAL ; SET STATE TO NORMAL
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LD A,(TERM_Y) ; GET CURRENT Y COORD INTO A
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OR A ; IS ZERO
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JP Z,REVERSE_SCROLL ; YES, SCROLL SCREEN DOWN ONE LINE
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DEC A ; NO, MOVE CRSR UP ONE LINE
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LD (TERM_Y),A ; STORE NEW CRSR POSITION
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JP GOTO_XY ; POSITION CRSR
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;__PERF_DIRECT_ADDRESS_____________________________________________________________________________
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;
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; PERFORM DIRECT CURSOR ADDRESSING
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;__________________________________________________________________________________________________
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PERF_DIRECT_ADDRESS:
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LD A,STATE_DIR_L ; SET STATE "WAITING FOR Y COORD"
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LD (TERMSTATE),A ;
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RET ;
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;__PERF_ENTER_GR___________________________________________________________________________________
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;
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; PERFORM ENTER GRAPHICS MODE
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;__________________________________________________________________________________________________
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PERF_ENTER_GR:
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LD A,0FFH ;
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LD (GR_MODE),A ; GRAPHICS MODE
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JP SET_STATE_NORMAL ;
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;__PERF_EXIT_GR____________________________________________________________________________________
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;
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; PERFORM EXIT GRAPHICS MODE
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;__________________________________________________________________________________________________
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PERF_EXIT_GR:
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LD A,00FH ;
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LD (GR_MODE),A ; GRAPHICS MODE
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JP SET_STATE_NORMAL ;
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;__PERF_ENTER_ALT___________________________________________________________________________________
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;
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; PERFORM ENTER ALTERNATE KEYPAD MODE
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;__________________________________________________________________________________________________
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PERF_ENTER_ALT:
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LD A,0FFH ;
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LD (ALT_KEYPAD),A ; ALT KEYPAD
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JP SET_STATE_NORMAL ;
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;__PERF_EXIT_ALT___________________________________________________________________________________
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;
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; PERFORM EXIT ALTERNATE KEYPAD MODE
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;__________________________________________________________________________________________________
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PERF_EXIT_ALT:
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LD A,00H ;
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LD (ALT_KEYPAD),A ; ALT KEYPAD
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JP SET_STATE_NORMAL ;
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;__PERF_ENTER_HOLD_________________________________________________________________________________
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;
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; PERFORM ENTER HOLD MODE
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;__________________________________________________________________________________________________
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PERF_ENTER_HOLD:
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; ********* IGNORE HOLD MODE !!
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JP SET_STATE_NORMAL ;
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;__PERF_EXIT_HOLD__________________________________________________________________________________
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;
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; PERFORM EXIT HOLD MODE
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;__________________________________________________________________________________________________
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PERF_EXIT_HOLD:
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; ********* IGNORE HOLD MODE !!
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JP SET_STATE_NORMAL ;
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;__SET_STATE_NORMAL________________________________________________________________________________
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;
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; SET NORMAL STATE
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;__________________________________________________________________________________________________
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SET_STATE_NORMAL:
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LD A,STATE_NORMAL ; RESET STATE
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LD (TERMSTATE),A ;
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RET
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;__PERF_ERASE_EOL__________________________________________________________________________________
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;
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; PERFORM ERASE FROM CURSOR POS TO END OF LINE
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;__________________________________________________________________________________________________
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PERF_ERASE_EOL:
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LD A,(TERM_X) ; GET CURRENT CURSOR X COORD
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LD C,A ; STORE IT IN C
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LD A,80 ; MOVE CURRENT LINE WIDTH INTO A
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SUB C ; GET REMAINING POSITIONS ON CURRENT LINE
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LD B,A ; MOVE IT INTO B
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LD A, 31 ; UPDATE TOGGLE VDU CHIP
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OUT (SY6545S),A ;
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PERF_ERASE_EOL_LOOP:
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CALL VDU_UPDATECHECK ; WAIT FOR VDU CHIP TO BE READY
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LD A,32 ; MOVE SPACE CHARACTER INTO A
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OUT (WRITR),A ; WRITE IT TO SCREEN, VDU WILL AUTO INC TO NEXT ADDRESS
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DJNZ PERF_ERASE_EOL_LOOP ; LOOP UNTIL DONE
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CALL GOTO_XY ; MOVE CURSOR BACK TO ORIGINAL POSITION
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CALL SET_STATE_NORMAL ; SET NORMAL STATE
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RET
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;__PERF_ERASE_EOS__________________________________________________________________________________
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;
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; PERFORM ERASE FROM CURSOR POS TO END OF SCREEN
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;__________________________________________________________________________________________________
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PERF_ERASE_EOS:
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LD HL,0780H ; SET SCREEN SIZE INTO HL
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PUSH HL ; MOVE IT TO DE
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POP DE ;
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LD A, 31 ; UPDATE TOGGLE VDU CHIP
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OUT (SY6545S),A ;
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PERF_ERASE_EOS_LOOP:
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CALL VDU_UPDATECHECK ; WAIT FOR VDU CHIP TO BE READY
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LD A, ' ' ; MOVE SPACE CHARACTER INTO A
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OUT (WRITR),A ; WRITE IT TO SCREEN, VDU WILL AUTO INC TO NEXT ADDRESS
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DEC DE ; DEC COUNTER
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LD A,D ; IS COUNTER 0 YET?
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OR E ;
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JP NZ,PERF_ERASE_EOS_LOOP ; NO, LOOP
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CALL GOTO_XY ; YES, MOVE CURSOR BACK TO ORIGINAL POSITION
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CALL SET_STATE_NORMAL ; SET NORMAL STATE
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RET
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;__PERF_IDENTIFY___________________________________________________________________________________
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;
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; PERFORM TERMINAL IDENTIFY FUNCTION
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;__________________________________________________________________________________________________
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PERF_IDENTIFY:
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LD A,ESC_KEY ;
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CALL KB_ENQUEUE ; STORE ON KB QUEUE
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LD A,'/' ;
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CALL KB_ENQUEUE ; STORE ON KB QUEUE
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LD A,'K' ;
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CALL KB_ENQUEUE ; STORE ON KB QUEUE
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CALL SET_STATE_NORMAL ; SET NORMAL STATE
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RET
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;__PERF_CURSOR_HOME________________________________________________________________________________
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;
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; PERFORM CURSOR HOME
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;__________________________________________________________________________________________________
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PERF_CURSOR_HOME:
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LD A,0 ; LOAD 0 INTO A
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LD (TERM_X),A ; SET X COORD
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LD (TERM_Y),A ; SET Y COORD
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CALL SET_STATE_NORMAL ; SET NORMAL STATE
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JP GOTO_XY ; MOVE CURSOR TO POSITION
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;__PERF_CURSOR_LEFT________________________________________________________________________________
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;
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; PERFORM CURSOR LEFT
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;__________________________________________________________________________________________________
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PERF_CURSOR_LEFT:
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LD A,(TERM_X) ; GET CURRENT X COORD INTO A
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OR A ; IS ZERO?
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JP Z,PERF_CURSOR_ABORT ; YES, ABORT
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DEC A ; MOVE ONE TO THE LEFT
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LD (TERM_X),A ; STORE NEW CURSOR POSITION
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CALL SET_STATE_NORMAL ; SET NORMAL STATE
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JP GOTO_XY ; MOVE CURSOR TO POSITION
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;__PERF_CURSOR_RIGHT_______________________________________________________________________________
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;
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; PERFORM CURSOR RIGHT
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;__________________________________________________________________________________________________
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PERF_CURSOR_RIGHT:
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LD A,(TERM_X) ; GET CURRENT X COORD INTO A
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CP 79 ; IS END OF LINE?
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JP Z,PERF_CURSOR_ABORT ; YES, ABORT
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INC A ; MOVE ONE TO THE RIGHT
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LD (TERM_X),A ; STORE NEW CURSOR POSITION
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CALL SET_STATE_NORMAL ; SET NORMAL STATE
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JP GOTO_XY ; MOVE CURSOR TO POSITION
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;__PERF_CURSOR_UP__________________________________________________________________________________
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;
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; PERFORM CURSOR UP
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;__________________________________________________________________________________________________
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PERF_CURSOR_UP:
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LD A,(TERM_Y) ; GET CURRENT Y COORD INTO A
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OR A ; IS ZERO?
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JP Z,PERF_CURSOR_ABORT ; YES, ABORT
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DEC A ; MOVE UP ONE POSITION
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LD (TERM_Y),A ; STORE NEW CURSOR POSITION
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|
CALL SET_STATE_NORMAL ; SET NORMAL STATE
|
|
JP GOTO_XY ; MOVE CURSOR TO POSTION
|
|
|
|
|
|
;__PERF_CURSOR_DOWN________________________________________________________________________________
|
|
;
|
|
; PERFORM CURSOR DOWN
|
|
;__________________________________________________________________________________________________
|
|
PERF_CURSOR_DOWN:
|
|
LD A,(TERM_Y) ; GET CURRENT Y COORD INTO A
|
|
CP 23 ; IS END OF SCREEN?
|
|
JP Z,PERF_CURSOR_ABORT ; YES, ABORT
|
|
INC A ; NO, MOVE DOWN ONE POSITION
|
|
LD (TERM_Y),A ; STORE NEW CURSOR POSITION
|
|
PERF_CURSOR_ABORT:
|
|
CALL SET_STATE_NORMAL ; SET NORMAL STATE
|
|
JP GOTO_XY ; MOVE CURSOR TO POSITION
|
|
|
|
|
|
|
|
|
|
|
|
;__DO_SCROLL_______________________________________________________________________________________
|
|
;
|
|
; SCROLL THE SCREEN UP ONE LINE
|
|
;__________________________________________________________________________________________________
|
|
DO_SCROLL:
|
|
PUSH AF ; STORE AF
|
|
DO_SCROLL1:
|
|
PUSH HL ; STORE HL
|
|
PUSH BC ; STORE BC
|
|
LD A, 31 ; TOGGLE VDU FOR UPDATE
|
|
OUT (SY6545S),A ;
|
|
CALL VDU_UPDATECHECK ; WAIT FOR VDU TO BE READY
|
|
LD HL, (VDU_DISPLAY_START) ; GET UP START OF DISPLAY
|
|
LD DE,0050H ; SET AMOUNT TO ADD
|
|
ADD HL,DE ; ADD TO START POS
|
|
LD (VDU_DISPLAY_START),HL ; STORE DISPLAY START
|
|
LD A, 12 ; SAVE START OF DISPLAY TO VDU
|
|
CALL VDU_HL2WREG_A ;
|
|
LD A,23 ; SET CURSOR TO BEGINNING OF LAST LINE
|
|
LD (TERM_Y),A ;
|
|
LD A,(TERM_X) ;
|
|
PUSH AF ; STORE X COORD
|
|
LD A,0 ;
|
|
LD (TERM_X),A ;
|
|
CALL GOTO_XY ; SET CURSOR POSITION TO BEGINNING OF LINE
|
|
CALL PERF_ERASE_EOL ; ERASE SCROLLED LINE
|
|
POP AF ; RESTORE X COORD
|
|
LD (TERM_X),A ;
|
|
CALL GOTO_XY ; SET CURSOR POSITION
|
|
POP BC ; RESTORE BC
|
|
POP HL ; RESTORE HL
|
|
POP AF ; RESTORE AF
|
|
RET ;
|
|
|
|
;__REVERSE_SCROLL__________________________________________________________________________________
|
|
;
|
|
; SCROLL THE SCREEN DOWN ONE LINE
|
|
;__________________________________________________________________________________________________
|
|
REVERSE_SCROLL:
|
|
PUSH AF ; STORE AF
|
|
PUSH HL ; STORE HL
|
|
PUSH BC ; STORE BC
|
|
LD A, 31 ; TOGGLE VDU FOR UPDATE
|
|
OUT (SY6545S),A ;
|
|
CALL VDU_UPDATECHECK ; WAIT FOR VDU TO BE READY
|
|
LD HL, (VDU_DISPLAY_START) ; GET UP START OF DISPLAY
|
|
LD DE,0FFB0H ; SET AMOUNT TO SUBTRACT (TWOS COMPLEMENT 50H)
|
|
ADD HL,DE ; ADD TO START POS
|
|
LD (VDU_DISPLAY_START),HL ; STORE DISPLAY START
|
|
LD A, 12 ; SAVE START OF DISPLAY TO VDU
|
|
CALL VDU_HL2WREG_A ;
|
|
LD A,23 ; SET CURSOR TO BEGINNING OF LAST LINE
|
|
LD (TERM_Y),A ;
|
|
LD A,(TERM_X) ;
|
|
PUSH AF ; STORE X COORD
|
|
LD A,0 ;
|
|
LD (TERM_X),A ;
|
|
CALL GOTO_XY ; SET CURSOR POSITION TO BEGINNING OF LINE
|
|
CALL PERF_ERASE_EOL ; ERASE SCROLLED LINE
|
|
POP AF ; RESTORE X COORD
|
|
LD (TERM_X),A ;
|
|
CALL GOTO_XY ; SET CURSOR POSITION
|
|
POP BC ; RESTORE BC
|
|
POP HL ; RESTORE HL
|
|
POP AF ; RESTORE AF
|
|
RET ;
|
|
|
|
|
|
|
|
;__IS_KBHIT________________________________________________________________________________________
|
|
;
|
|
; WAS A KEY PRESSED?
|
|
;__________________________________________________________________________________________________
|
|
IS_KBHIT:
|
|
CALL KB_PROCESS ; CALL KEYBOARD ROUTINE
|
|
LD A,(KB_QUEUE_PTR) ; ASK IF KEYBOARD HAS KEY WAITING
|
|
OR A
|
|
JP Z,CIO_IDLE
|
|
LD A,$FF ; SIGNAL DATA PENDING
|
|
RET
|
|
|
|
|
|
;__WAIT_KBHIT______________________________________________________________________________________
|
|
;
|
|
; WAIT FOR A KEY PRESS
|
|
;__________________________________________________________________________________________________
|
|
WAIT_KBHIT:
|
|
CALL IS_KBHIT
|
|
JR Z,WAIT_KBHIT
|
|
RET
|
|
|
|
|
|
;__GET_KEY_________________________________________________________________________________________
|
|
;
|
|
; GET KEY PRESS VALUE
|
|
;__________________________________________________________________________________________________
|
|
GET_KEY:
|
|
CALL WAIT_KBHIT ; WAIT FOR A KEY
|
|
LD A,(KB_QUEUE_PTR) ; GET QUEUE POINTER
|
|
OR A ;
|
|
RET Z ; ABORT IF QUEUE EMPTY
|
|
PUSH BC ; STORE BC
|
|
LD B,A ; STORE QUEUE COUNT FOR LATER
|
|
PUSH HL ; STORE HL
|
|
LD A,(KB_QUEUE) ; GET TOP BYTE FROM QUEUE
|
|
PUSH AF ; STORE IT
|
|
LD HL,KB_QUEUE ; GET POINTER TO QUEUE
|
|
GET_KEY_LOOP: ;
|
|
INC HL ; POINT TO NEXT VALUE IN QUEUE
|
|
LD A,(HL) ; GET VALUE
|
|
DEC HL ;
|
|
LD (HL),A ; MOVE IT UP ONE
|
|
INC HL ;
|
|
DJNZ GET_KEY_LOOP ; LOOP UNTIL DONE
|
|
LD A,(KB_QUEUE_PTR) ; DECREASE QUEUE POINTER BY ONE
|
|
DEC A ;
|
|
LD (KB_QUEUE_PTR),A ;
|
|
POP AF ; RESTORE VALUE
|
|
POP HL ; RESTORE HL
|
|
POP BC ; RESTORE BC
|
|
RET
|
|
|
|
|
|
|
|
|
|
|
|
|
|
;__VDUINIT__________________________________________________________________________________________
|
|
;
|
|
; INITIALIZE VDU
|
|
;__________________________________________________________________________________________________
|
|
VDUINIT:
|
|
PUSH AF ; STORE AF
|
|
PUSH DE ; STORE DE
|
|
PUSH HL ; STORE HL
|
|
|
|
CALL VDU_CRTINIT ; INIT 6545 VDU CHIP
|
|
LD A, 31 ; TOGGLE VDU FOR UPDATE
|
|
OUT (SY6545S),A ;
|
|
LD HL,0 ; SET-UP START OF DISPLAY
|
|
LD DE, 2048 ; SET-UP DISPLAY SIZE
|
|
LD A, 18 ; WRITE HL TO R18 AND R19 (UPDATE ADDRESS)
|
|
CALL VDU_HL2WREG_A ;
|
|
LD A, 31 ; TOGGLE VDU FOR UPDATE
|
|
OUT (SY6545S),A ;
|
|
VDU_CRTSPACELOOP: ;
|
|
CALL VDU_UPDATECHECK ; WAIT FOR VDU TO BE READY
|
|
LD A, ' ' ; CLEAR SCREEN
|
|
OUT (WRITR),A ; SEND SPACE TO DATAPORT
|
|
DEC DE ; DECREMENT DE
|
|
LD A,D ; IS ZERO?
|
|
OR E ;
|
|
JP NZ, VDU_CRTSPACELOOP ; NO, LOOP
|
|
LD A, 31 ; TOGGLE VDU FOR UPDATE
|
|
OUT (SY6545S),A ;
|
|
LD HL, 0 ; SET UP START OF DISPLAY
|
|
LD (VDU_DISPLAY_START),HL ; STORE DISPLAY START
|
|
LD A, 12 ; SAVE START OF DISPLAY TO VDU
|
|
CALL VDU_HL2WREG_A ;
|
|
POP HL ;
|
|
POP DE ;
|
|
POP AF ;
|
|
CALL PERF_CURSOR_HOME ; CURSOR HOME
|
|
CALL PERF_ERASE_EOS ; CLEAR SCREEN
|
|
CALL VDU_CURSORON ; TURN ON CURSOR
|
|
RET
|
|
|
|
|
|
;;__DSPMATRIX_______________________________________________________________________________________
|
|
;;
|
|
;; DISPLAY INTRO SCREEN
|
|
;;__________________________________________________________________________________________________
|
|
;DSPMATRIX:
|
|
; CALL PERF_CURSOR_HOME ; RESET CURSOR TO HOME POSITION
|
|
; LD HL,TESTMATRIX ; SET HL TO SCREEN IMAGE
|
|
; LD DE, 1918 ; SET IMAGE SIZE
|
|
;DSPMATRIX_LOOP:
|
|
; LD A,(HL) ; GET NEXT CHAR FROM IMAGE
|
|
; CALL VDU_PUTCHAR ; DUMP CHAR TO DISPLAY
|
|
; INC HL ; INC POINTER
|
|
; DEC DE ; DEC COUNTER
|
|
; LD A,D ; IS COUNTER ZERO?
|
|
; OR E ;
|
|
; JP NZ,DSPMATRIX_LOOP ; NO, LOOP
|
|
; CALL PERF_CURSOR_HOME ; YES, RESET CURSOR TO HOME POSITION
|
|
; RET
|
|
|
|
;TESTMATRIX:
|
|
; .TEXT "0 1 2 3 4 5 6 7 "
|
|
; .TEXT "01234567890123456789012345678901234567890123456789012345678901234567890123456789"
|
|
; .TEXT "2 "
|
|
; .TEXT "3 "
|
|
; .TEXT "4 "
|
|
; .TEXT "5 "
|
|
; .TEXT "6 NN NN 8888 VV VV EEEEEEEEEE MM MM "
|
|
; .TEXT "7 NNNN NN 88 88 VV VV EE MMMM MMMM "
|
|
; .TEXT "8 NN NN NN 88 88 VV VV EE MM MM MM MM "
|
|
; .TEXT "9 NN NNNN 88 88 VV VV EE MM MM MM "
|
|
; .TEXT "10 NN NN 8888 VV VV EEEEEEE MM MM "
|
|
; .TEXT "11 NN NN 88 88 VV VV EE MM MM "
|
|
; .TEXT "12 NN NN 88 88 VV VV EE MM MM "
|
|
; .TEXT "13 NN NN 88 88 VVV EE MM MM "
|
|
; .TEXT "14 NN NN 8888 V EEEEEEEEEE MM MM S B C "
|
|
; .TEXT "15 "
|
|
; .TEXT "16 "
|
|
; .TEXT "17 "
|
|
; .TEXT "18 * VDU OK * VT-52 EMULATION "
|
|
; .TEXT "19 "
|
|
; .TEXT "20 ** PRESS ANY KEY TO ENTER TERMINAL MODE ** "
|
|
; .TEXT "21 "
|
|
; .TEXT "22 "
|
|
; .TEXT "23 "
|
|
; .TEXT "24 "
|
|
|
|
|
|
;__VDU_HL2WREG_A___________________________________________________________________________________
|
|
;
|
|
; WRITE VALUE IN HL TO REGISTER IN A
|
|
; A: REGISTER TO UPDATE
|
|
; HL: WORD VALUE TO WRITE
|
|
;__________________________________________________________________________________________________
|
|
VDU_HL2WREG_A:
|
|
PUSH BC ; STORE BC
|
|
PUSH AF ; STORE AF
|
|
CALL VDU_UPDATECHECK ; WAIT FOR VDU TO BE READY
|
|
POP AF ; RESTORE AF
|
|
LD C, SY6545S ; ADDRESS REGISTER
|
|
OUT (C), A ; SELECT REGISTER (A)
|
|
INC C ; NEXT WRITE IN REGISTER
|
|
OUT (C), H ; WRITE H TO SELECTED REGISTER
|
|
DEC C ; NEXT WRITE SELECT REGISTER
|
|
INC A ; INCREASE REGISTER NUMBER
|
|
OUT (C), A ; SELECT REGISTER (A+1)
|
|
INC C ; NEXT WRITE IN REGISTER
|
|
OUT (C), L ; WRITE L TO SELECTED REGISTER
|
|
POP BC ; RESTORE BC
|
|
RET
|
|
|
|
;__VDU_UPDATECHECK_________________________________________________________________________________
|
|
;
|
|
; WAIT FOR VDU TO BE READY
|
|
;__________________________________________________________________________________________________
|
|
VDU_UPDATECHECK:
|
|
IN A,(SY6545S) ; READ ADDRESS/STATUS REGISTER
|
|
BIT 7,A ; IF BIT 7 = 1 THAN AN UPDATE STROBE HAS OCCURED
|
|
RET NZ ;
|
|
JR VDU_UPDATECHECK ; WAIT FOR READY
|
|
|
|
VDU_INIT6845:
|
|
; DB 07FH, 50H, 60H, 7CH, 19H, 1FH, 19H, 1AH, 78H, 09H, 60H, 09H, 00H, 00H, 00H, 00H
|
|
|
|
; CCIR 625/50 VERSION (USED IN MOST OF THE WORLD)
|
|
; JUMPER K1 2-3, K2 1-2 FOR 2MHz CHAR CLOCK
|
|
.DB 07FH ; R0 TOTAL NUMBER OF HORIZONTAL CHARACTERS (DETERMINES HSYNC)
|
|
.DB 050H ; R1 NUMBER OF HORIZONTAL CHARACTERS DISPLAYED (80 COLUMNS)
|
|
.DB 060H ; R2 HORIZONTAL SYNC POSITION
|
|
.DB 00CH ; R3 SYNC WIDTHS
|
|
.DB 01EH ; R4 VERTICAL TOTAL (TOTAL CHARS IN A FRAME -1)
|
|
.DB 002H ; R5 VERTICAL TOTAL ADJUST (
|
|
.DB 018H ; R6 VERTICAL DISPLAYED (24 ROWS)
|
|
.DB 01CH ; R7 VERTICAL SYNC
|
|
.DB 078H ; R8 MODE B7=0 TRANSPARENT UPDATE DURING BLANKING
|
|
; B6=1 PIN 34 IS UPDATE STROBE
|
|
; B5=1 DELAY CURSOR 1 CHARACTER
|
|
; B4=1 DELAY DISPLAY ENABLE 1 CHARACTER
|
|
; B3=1 TRANSPARENT MEMORY ADDRESSING
|
|
; B2=0 RAM STRAIGHT BINARY ADDRESSING
|
|
; B1,B0=0 NON-INTERLACE
|
|
.DB 009H ; R9 SCAN LINE (LINES PER CHAR AND SPACING -1)
|
|
.DB 060H ; R10 CURSOR START RASTER
|
|
.DB 009H ; R11 CURSOR END RASTER
|
|
.DB 00H ; R12 START ADDRESS HI
|
|
.DB 00H ; R13 START ADDRESS LO
|
|
.DB 00H ; R14 CURSOR ADDRESS HI
|
|
.DB 00H ; R15 CURSOR ADDRESS LO
|
|
; THE CCIR 625/50 TELEVISION STANDARD HAS 625 LINES INTERLACED AT 50 FIELDS PER SECOND. THIS WORKS
|
|
; OUT AS 50 FIELDS OF 312.5 LINES PER SECOND NON-INTERLACED AS USED HERE.
|
|
; HORIZONTAL LINE WIDTH IS 64uS. FOR A 2 MHz CHARACTER CLOCK (R0+1)/2000000 = 64uS
|
|
; NEAREST NUMBER OF LINES IS 312 = (R4+1) * (R9+1) + R5.
|
|
; 15625 / 312 = 50.08 FIELDS PER SECOND (NEAR ENOUGH-DGG)
|
|
|
|
|
|
;__VDU_CRTINIT_____________________________________________________________________________________
|
|
;
|
|
; INIT VDU CHIP
|
|
;__________________________________________________________________________________________________
|
|
VDU_CRTINIT:
|
|
PUSH AF ; STORE AF
|
|
PUSH BC ; STORE BC
|
|
PUSH DE ; STORE DE
|
|
PUSH HL ; STORE HL
|
|
LD BC,010F2h ; B = 16, C = SY6545S
|
|
LD HL,VDU_INIT6845 ; HL = POINTER TO THE DEFAULT VALUES
|
|
XOR A ; A = 0
|
|
VDU_CRTINITLOOP:
|
|
OUT (C), A ; SY6545S SET REGISTER
|
|
INC C ; 0F3h
|
|
LD D,(HL) ; LOAD THE NEXT DEFAULT VALUE IN D
|
|
OUT (C),D ; 0F3h ADDRESS
|
|
DEC C ; SY6545S
|
|
INC HL ; TAB + 1
|
|
INC A ; REG + 1
|
|
DJNZ VDU_CRTINITLOOP ; LOOP UNTIL DONE
|
|
POP HL ; RESTORE HL
|
|
POP DE ; RESTORE DE
|
|
POP BC ; RESTORE BC
|
|
POP AF ; RESTORE AF
|
|
RET
|
|
|
|
|
|
;__VDU_CURSORON____________________________________________________________________________________
|
|
;
|
|
; TURN ON CURSOR
|
|
;__________________________________________________________________________________________________
|
|
VDU_CURSORON:
|
|
PUSH AF ; STORE AF
|
|
LD A, 060h ; SET CURSOR VALUE
|
|
JP VDU_CURSORSET ;
|
|
|
|
;__VDU_CURSOROFF___________________________________________________________________________________
|
|
;
|
|
; TURN OFF CURSOR
|
|
;__________________________________________________________________________________________________
|
|
VDU_CURSOROFF:
|
|
PUSH AF ; STORE AF
|
|
LD A, 020h ; SET CURSOR VALUE
|
|
VDU_CURSORSET:
|
|
PUSH BC ; STORE BC
|
|
LD C,A ; MOVE A TO C
|
|
CALL VDU_UPDATECHECK ; WAIT FOR VDU TO BE READY
|
|
LD A, 10 ; R10, CURSOR START AND STATUS
|
|
OUT (SY6545S), A ;
|
|
LD A,C ; STORE CURSOR VALUE
|
|
OUT (SY6545D), A ;
|
|
POP BC ; RESTORE BC
|
|
POP AF ; RESTORE AF
|
|
RET
|
|
|
|
;__GOTO_XY_________________________________________________________________________________________
|
|
;
|
|
; MOVE CURSOR TO POSITON IN TERM_X AND TERM_Y
|
|
;__________________________________________________________________________________________________
|
|
GOTO_XY:
|
|
PUSH AF ; STORE AF
|
|
|
|
LD A,(TERM_Y) ; PLACE Y COORD IN A
|
|
CP 24 ; IS 24?
|
|
JP Z,DO_SCROLL1 ; YES, MUST SCROLL
|
|
|
|
PUSH BC ; STORE BC
|
|
PUSH DE ; STORE DE
|
|
LD A,(TERM_X) ;
|
|
LD H,A ;
|
|
LD A,(TERM_Y) ;
|
|
LD L,A ;
|
|
PUSH HL ; STORE HL
|
|
LD B, A ; B = Y COORD
|
|
LD DE, 80 ; MOVE LINE LENGTH INTO DE
|
|
LD HL, 0 ; MOVE 0 INTO HL
|
|
LD A, B ; A=B
|
|
CP 0 ; Y=0?
|
|
JP Z, VDU_YLOOPEND ; THEN DO NOT MULTIPLY BY 80
|
|
VDU_YLOOP: ; HL = 80 * Y
|
|
ADD HL, DE ; HL=HL+DE
|
|
DJNZ VDU_YLOOP ; LOOP
|
|
VDU_YLOOPEND: ;
|
|
POP DE ; DE = ORG HL
|
|
LD E, D ; E = X
|
|
LD D, 0 ; D = 0
|
|
ADD HL, DE ; HL = HL + X
|
|
LD (VDU_DISPLAYPOS), HL ;
|
|
PUSH HL ;
|
|
POP DE ;
|
|
LD HL,(VDU_DISPLAY_START) ;
|
|
ADD HL,DE ;
|
|
LD A, 18 ; SET UPDATE ADDRESS IN VDU
|
|
CALL VDU_HL2WREG_A ;
|
|
LD A, 31 ; TOGGLE VDU FOR UPDATE
|
|
OUT (SY6545S),A ;
|
|
LD A, 14 ; SET CURSOR POS
|
|
CALL VDU_HL2WREG_A ;
|
|
POP DE ; RESTORE DE
|
|
POP BC ; RESTORE BC
|
|
POP AF ; RESTORE AF
|
|
RET
|
|
|
|
;__VDU_PUTCHAR______________________________________________________________________________________
|
|
;
|
|
; PLACE CHARACTER ON SCREEN
|
|
; A: CHARACTER TO OUTPUT
|
|
;__________________________________________________________________________________________________
|
|
VDU_PUTCHAR:
|
|
PUSH DE ; STORE DE
|
|
PUSH AF ; STORE AF
|
|
LD A,(TERM_X) ; PLACE X COORD IN A
|
|
INC A ; INC X COORD
|
|
LD (TERM_X),A ; STORE IN A
|
|
CP 80 ; IS 80?
|
|
JP NZ,VDU_PUTCHAR1 ; NO, PLACE CHAR ON DISPLAY
|
|
LD A,0 ; YES, WRAP TO NEXT LINE
|
|
LD (TERM_X),A ; STORE X
|
|
LD A,(TERM_Y) ; A= Y COORD
|
|
INC A ; INC Y COORD
|
|
LD (TERM_Y),A ; STORE Y
|
|
CP 24 ; IS PAST END OF SCREEN?
|
|
CALL Z,GOTO_XY ; YES, HANDLE SCROLLING
|
|
VDU_PUTCHAR1: ;
|
|
CALL VDU_UPDATECHECK ; WAIT FOR VDU TO BE READY
|
|
;
|
|
LD A, 31 ; TOGGLE VDU FOR UPDATE
|
|
OUT (SY6545S),A ;
|
|
;
|
|
CALL VDU_UPDATECHECK ; WAIT FOR VDU TO BE READY
|
|
;
|
|
LD A, 31 ; TOGGLE VDU FOR UPDATE
|
|
OUT (SY6545S),A ;
|
|
;
|
|
POP AF ; RESTORE CHAR
|
|
OUT (WRITR), A ; OUTPUT CHAR TO VDU
|
|
PUSH AF ; STORE AF
|
|
PUSH HL ; STORE HL
|
|
LD HL, (VDU_DISPLAYPOS) ; GET CURRENT DISPLAY ADDRESS
|
|
INC HL ; INCREMENT IT
|
|
LD (VDU_DISPLAYPOS), HL ; STORE CURRENT DISPLAY ADDRESS
|
|
PUSH HL ; MOVE HL TO DE
|
|
POP DE ;
|
|
LD HL,(VDU_DISPLAY_START) ;
|
|
ADD HL,DE ;
|
|
LD A, 14 ; UPDATE CURSOR POSITION IN HARDWARE
|
|
CALL VDU_HL2WREG_A ;
|
|
POP HL ; RESTORE HL
|
|
POP AF ; RESTORE AF
|
|
POP DE ; RESTORE DE
|
|
RET
|
|
|
|
|
|
|
|
|
|
|
|
|
|
;;__PR_OUTCHAR______________________________________________________________________________________
|
|
;;
|
|
;; PR_OUTCHAR- OUTPUT CHAR TO PRINTER PORT
|
|
;; A: CHAR TO OUTPUT
|
|
;;__________________________________________________________________________________________________
|
|
;PR_OUTCHAR:
|
|
; PUSH AF ; STORE AF
|
|
;PR_OUTCHAR_LOOP:
|
|
; IN A,(VPPIB) ; GET STATUS INFO
|
|
; AND 10000000B ; ONLY INTERESTED IN BUSY FLAG
|
|
; JP NZ,PR_OUTCHAR_LOOP ; LOOP IF BUSY
|
|
; POP AF ; RESTORE AF
|
|
; OUT (VPPIA),A ; OUTPUT DATA TO PORT
|
|
; LD A,1 ; 01 SECOND DELAY
|
|
; CALL KB_DELAY ; IGNORE ANYTHING BACK AFTER A RESET
|
|
; CALL KB_PORTCBIT0LOW ; STROBE
|
|
; LD A,1 ; 01 SECOND DELAY
|
|
; CALL KB_DELAY ; IGNORE ANYTHING BACK AFTER A RESET
|
|
; CALL KB_PORTCBIT0HIGH ; STROBE
|
|
; RET
|
|
|
|
;;__PR_INITIALIZE___________________________________________________________________________________
|
|
;;
|
|
;; INITIALISE - SET UP PORT FOR PRINTING
|
|
;;__________________________________________________________________________________________________
|
|
;PR_INITIALIZE:
|
|
; CALL KB_PORTCBIT0HIGH ; STROBE
|
|
; CALL KB_PORTCBIT1HIGH ; FORM FEED
|
|
; CALL KB_PORTCBIT2LOW ; DEVICE SELECT
|
|
; CALL KB_PORTCBIT3LOW ; DEVICE INIT
|
|
; LD A,200 ; 1 SECOND DELAY
|
|
; CALL KB_DELAY ; IGNORE ANYTHING BACK AFTER A RESET
|
|
; CALL KB_PORTCBIT3HIGH ; DEVICE INIT
|
|
; RET
|
|
|
|
|
|
;__KB_INITIALIZE___________________________________________________________________________________
|
|
;
|
|
; INITIALISE - CLEAR SOME LOCATIONS AND SEND A RESET TO THE KEYBOARD
|
|
;__________________________________________________________________________________________________
|
|
KB_INITIALIZE:
|
|
CALL KB_SETPORTC ; SETS PORT C SO CAN INPUT AND OUTPUT
|
|
CALL KB_RESET ; RESET TO THE KEYBOARD
|
|
LD A,200 ; 1 SECOND DELAY AS KEYBOARD SENDS STUFF BACK WHEN RESET
|
|
CALL KB_DELAY ; IGNORE ANYTHING BACK AFTER A RESET
|
|
LD A,0 ; EMPTY KB QUEUE
|
|
LD (KB_QUEUE_PTR),A ;
|
|
RET
|
|
|
|
|
|
;__KB_RESET________________________________________________________________________________________
|
|
;
|
|
; RESET THE KEYBOARD
|
|
;__________________________________________________________________________________________________
|
|
KB_RESET:
|
|
CALL KB_DATAHIGH ;
|
|
CALL KB_CLOCKHIGH ;
|
|
LD B,255 ;
|
|
SF1: DJNZ SF1 ;
|
|
CALL KB_CLOCKLOW ; STEP 1
|
|
LD B,255 ;
|
|
SF2: DJNZ SF2 ;
|
|
CALL KB_DATALOW ; STEP 2
|
|
CALL KB_CLOCKHIGH ; STEP 3
|
|
CALL KB_WAITCLOCKLOW ; STEP 4
|
|
LD B,9 ; 8 DATA BITS + 1 PARITY BIT LOW
|
|
SF3: PUSH BC ;
|
|
CALL KB_DATAHIGH ; STEP 5
|
|
CALL KB_WAITCLOCKHIGH ; STEP 6
|
|
CALL KB_WAITCLOCKLOW ; STEP 7
|
|
POP BC ;
|
|
DJNZ SF3 ;
|
|
CALL KB_DATAHIGH ; STEP9
|
|
CALL KB_WAITCLOCKLOW ; STEP 10 COULD READ THE ACK BIT HERE IF WANT TO
|
|
CALL KB_WAITCLOCKHIGH ; STEP 11
|
|
LD B,255 ;
|
|
SF4: DJNZ SF4 ; FINISH UP DELAY
|
|
RET
|
|
|
|
;__KB_SETPORTC_____________________________________________________________________________________
|
|
;
|
|
; SETUP PORT C OF 8255 FOR KEYBOARD
|
|
;__________________________________________________________________________________________________
|
|
KB_SETPORTC:
|
|
LD A,10000010B ; A=OUT B=IN, C HIGH=OUT, CLOW=OUT
|
|
OUT (VPPICONT),A ; PPI CONTROL PORT
|
|
LD A,00000000B ; PORT A TO ZERO AS NEED THIS FOR COMMS TO WORK
|
|
OUT (VPPIA),A ; PPI PORT A
|
|
CALL KB_DATAHIGH ;
|
|
CALL KB_CLOCKHIGH ;
|
|
LD A,0 ;
|
|
LD (CAPSLOCK),A ; SET CAPSLOCK OFF TO START
|
|
LD (CTRL),A ; CONTROL OFF
|
|
LD (NUMLOCK),A ; NUMLOCK OFF
|
|
RET
|
|
;_________________________________________________________________________________________________
|
|
;
|
|
; PORT C BIT ROUTINES
|
|
;__________________________________________________________________________________________________
|
|
KB_PORTCBIT0HIGH: ;
|
|
LD A,01110001B ; SEE THE 8255 DATA SHEET
|
|
JP KB_SETBITS ;
|
|
KB_PORTCBIT1HIGH: ;
|
|
LD A,01110011B ; SEE THE 8255 DATA SHEET
|
|
JP KB_SETBITS ;
|
|
KB_PORTCBIT2HIGH: ;
|
|
LD A,01110101B ; SEE THE 8255 DATA SHEET
|
|
JP KB_SETBITS ;
|
|
KB_PORTCBIT3HIGH: ;
|
|
LD A,01110111B ; SEE THE 8255 DATA SHEET
|
|
JP KB_SETBITS ;
|
|
KB_PORTCBIT0LOW: ;
|
|
LD A,01110000B ; SEE THE 8255 DATA SHEET
|
|
JP KB_SETBITS ;
|
|
KB_PORTCBIT1LOW: ;
|
|
LD A,01110010B ; SEE THE 8255 DATA SHEET
|
|
JP KB_SETBITS ;
|
|
KB_PORTCBIT2LOW: ;
|
|
LD A,01110100B ; SEE THE 8255 DATA SHEET
|
|
JP KB_SETBITS ;
|
|
KB_PORTCBIT3LOW: ;
|
|
LD A,01110110B ; SEE THE 8255 DATA SHEET
|
|
JP KB_SETBITS ;
|
|
KB_DATAHIGH:
|
|
KB_PORTCBIT4HIGH: ;
|
|
LD A,01111001B ; SEE THE 8255 DATA SHEET
|
|
JP KB_SETBITS ;
|
|
KB_DATALOW: ;
|
|
KB_PORTCBIT4LOW: ;
|
|
LD A,01111000B ; SEE THE 8255 DATA SHEET
|
|
JP KB_SETBITS ;
|
|
KB_CLOCKHIGH: ;
|
|
KB_PORTCBIT5HIGH: ;
|
|
LD A,01111011B ; BIT 5 HIGH
|
|
JP KB_SETBITS ;
|
|
KB_CLOCKLOW: ;
|
|
PORTCBIT5LOW: ;
|
|
LD A,01111010B ;
|
|
KB_SETBITS: ;
|
|
OUT (VPPICONT),A ;
|
|
RET ;
|
|
|
|
|
|
|
|
;__KB_WAITCLOCKLOW_________________________________________________________________________________
|
|
;
|
|
; WAITCLOCKLOW SAMPLES DATA BIT 0, AND WAITS TILL
|
|
; IT GOES LOW, THEN RETURNS
|
|
; ALSO TIMES OUT AFTER 0 001 SECONDS
|
|
; USES A, CHANGES B
|
|
;__________________________________________________________________________________________________
|
|
KB_WAITCLOCKLOW:
|
|
LD B,255 ; FOR TIMEOUT COUNTER
|
|
WL1: IN A,(VPPIB) ; GET A BYTE FROM PORT B
|
|
BIT 1,A ; TEST THE CLOCK BIT
|
|
RET Z ; EXIT IF IT WENT LOW
|
|
DJNZ WL1 ; LOOP B TIMES
|
|
RET
|
|
|
|
|
|
;__KB_WAITCLOCKHIGH_________________________________________________________________________________
|
|
;
|
|
; WAITCLOCKHIGH SAMPLES DATA BIT 0, AND WAITS TILL
|
|
; IT GOES HIGH, THEN RETURNS
|
|
; ALSO TIMES OUT AFTER 0 001 SECONDS
|
|
; USES A, CHANGES B
|
|
;__________________________________________________________________________________________________
|
|
KB_WAITCLOCKHIGH:
|
|
LD B,255 ; FOR TIMEOUT COUNTER
|
|
WH1: IN A,(VPPIB) ; GET A BYTE FROM PORT B
|
|
BIT 1,A ; TEST THE CLOCK BIT
|
|
RET NZ ; EXIT IF IT WENT HIGH
|
|
DJNZ WH1 ; LOOP B TIMES
|
|
RET
|
|
|
|
;__KB_DELAY________________________________________________________________________________________
|
|
;
|
|
; PASS A - DELAY IS B*0 005 SECONDS, BCDEHL ALL PRESERVED
|
|
;__________________________________________________________________________________________________
|
|
KB_DELAY:
|
|
PUSH BC ; STORE ALL VARIABLES
|
|
PUSH DE ;
|
|
PUSH HL ;
|
|
LD B,A ; PUT THE VARIABLE DELAY IN B
|
|
LD DE,1 ;
|
|
LOOP1: LD HL,740 ; ADJUST THIS VALUE FOR YOUR CLOCK 1481=3 68MHZ, 3219=8MHZ (TEST WITH A=1000=10 SECS)
|
|
LOOP2: SBC HL,DE ; HL-1
|
|
JR NZ,LOOP2 ;
|
|
DJNZ LOOP1 ;
|
|
POP HL ; RESTORE VARIABLES
|
|
POP DE ;
|
|
POP BC ;
|
|
RET ;
|
|
|
|
|
|
;__KB_PROCESS______________________________________________________________________________________
|
|
;
|
|
; A=0 IF WANT TO KNOW IF A BYTE IS AVAILABLE, AND A=1 TO ASK FOR THE BYTE
|
|
;__________________________________________________________________________________________________
|
|
KB_PROCESS:
|
|
CALL SKIP ; DON'T TEST EVERY ONE AS TAKES TIME
|
|
OR A ; IS IT ZERO
|
|
RET Z ; RETURN IF ZERO
|
|
CALL KB_WAITBYTE ; TEST KEYBOARD TIMES OUT AFTER A BIT
|
|
CALL KB_DECODECHAR ; RETURNS CHAR OR 0 FOR THINGS LIKE KEYUP, SOME RETURN DIRECTLY TO CP/M
|
|
RET ; RETURN TO CP/M
|
|
|
|
|
|
;-----------------------------------------------
|
|
; CPM CALLS THE KEYBOARD QUITE FREQUENTLY IF A KEYBOARD WAS LIKE A UART WHICH CAN BE CHECKED
|
|
; WITH ONE INSTRUCTION, THAT WOULD BE FINE BUT CHECKING A KEYBOARD INVOLVES PUTTING THE CLOCK LINE LOW
|
|
; THEN WAITING SOME TIME FOR A POSSIBLE REPLY, THEN READING IN BITS WITH TIMEOUTS AND THEN RETURNING
|
|
; THIS SLOWS DOWN A LOT OF CP/M PROCESSES, EG TRY TYPE MYPROG AND PRINTING OUT TEXT
|
|
SKIP:
|
|
LD B,0 ;
|
|
LD A,(SKIPCOUNT) ;
|
|
DEC A ; SUBTRACT 1
|
|
LD (SKIPCOUNT),A ; STORE IT BACK
|
|
CP 0 ;
|
|
JP NZ,SK1 ; WORDSTAR IS VERY SLOW EVEN TRIED A VALUE OF 5 TO 200 HERE
|
|
LD A,200 ; ONLY ACT ON EVERY N CALLS - BIGGER=BETTER BECAUSE THIS SUB IS QUICKER THAN READBITS
|
|
LD (SKIPCOUNT),A ; RESET COUNTER
|
|
LD B,1 ; FLAG TO SAY RESET COUNTER
|
|
SK1: ;
|
|
LD A,B ; RETURN THE VALUE IN A
|
|
RET
|
|
|
|
|
|
;__KB_DECODECHAR____________________________________________________________________________________
|
|
;
|
|
; DECODE CHARACTER PASS A AND PRINTS OUT THE CHAR
|
|
; ON THE LCD SCREEN
|
|
;__________________________________________________________________________________________________
|
|
KB_DECODECHAR:
|
|
CP 0 ; IS IT ZERO
|
|
RET Z ; RETURN IF A ZERO - NO NEED TO DO ANYTHING
|
|
CP 0F0H ; IS A KEY UP (NEED TO DO SPECIAL CODE FOR SHIFT)
|
|
JP Z,DECKEYUP ; IGNORE CHAR UP
|
|
CP 0E0H ; TWO BYTE KEYPRESSES
|
|
JP Z,TWOBYTE ;
|
|
CP 058H ; CAPS LOCK SO TOGGLE
|
|
JP Z,CAPSTOG ;
|
|
CP 12H ; SHIFT (DOWN, BECAUSE UP WOULD BE TRAPPED BY 0F ABOVE)
|
|
JP Z,SHIFTDOWN ;
|
|
CP 59H ; OTHER SHIFT KEY
|
|
JP Z,SHIFTDOWN ;
|
|
CP 014H ; CONTROL KEY
|
|
JP Z,CONTROLDOWN ;
|
|
CP 05AH ; ENTER KEY
|
|
JP Z,RETURN ;
|
|
CP 066H ; BACKSPACE KEY
|
|
JP Z,BACKSPACE ;
|
|
CP 0DH ; TAB KEY
|
|
JP Z,TABKEY ;
|
|
CP 076H ; ESCAPE KEY
|
|
JP Z,ESCAPE ;
|
|
LD C,A ;
|
|
LD B,0 ; ADD BC TO HL
|
|
LD HL,NORMALKEYS ; OFFSET TO ADD
|
|
ADD HL,BC ;
|
|
JP TESTCONTROL ; IS THE CONTROL KEY DOWN?
|
|
DC1: LD A,(CAPSLOCK) ;
|
|
CP 0 ; IS IT 0, IF SO THEN DON'T ADD THE CAPS OFFSET
|
|
JR Z,DC2 ;
|
|
LD C,080H ; ADD ANOTHER 50H TO SMALLS TO GET CAPS
|
|
ADD HL,BC ;
|
|
DC2: LD A,(HL) ;
|
|
CALL KB_ENQUEUE ; STORE ON KB QUEUE
|
|
RET ;
|
|
TESTCONTROL:
|
|
LD A,(CTRL) ;
|
|
CP 0 ; IS CONTROL BEING HELD DOWN?
|
|
JP Z,DC1 ; NO SO GO BACK TO TEST CAPS LOCK ON
|
|
LD A,(HL) ; GET THE LETTER, SHOULD BE SMALLS
|
|
SUB 96 ; A=97 SO SUBTRACT 96 A=1=^A
|
|
CALL KB_ENQUEUE ; STORE ON KB QUEUE
|
|
RET ; RETURN INSTEAD OF THE RET AFTER DC2
|
|
TABKEY: ;
|
|
LD A,9 ;
|
|
CALL KB_ENQUEUE ; STORE ON KB QUEUE
|
|
RET ;TAB
|
|
BACKSPACE: ;
|
|
LD A,8 ; BACKSPACE
|
|
CALL KB_ENQUEUE ; STORE ON KB QUEUE
|
|
RET ;
|
|
ESCAPE: ;
|
|
LD A,27 ;
|
|
CALL KB_ENQUEUE ; STORE ON KB QUEUE
|
|
RET ;
|
|
RETURN: ;
|
|
LD A,13 ; CARRIAGE RETURN
|
|
CALL KB_ENQUEUE ; STORE ON KB QUEUE
|
|
RET ;
|
|
DECKEYUP:
|
|
CALL KB_WAITBYTE ; IGNORE KEY UP THROW AWAY THE CHARACTER UNLESS A SHIFT
|
|
CP 012H ; IS IT A SHIFT
|
|
JP Z,SHIFTUP ;
|
|
CP 59H ; OTHER SHIFT KEY
|
|
JP Z,SHIFTUP ;
|
|
CP 014H ; CONTROL UP
|
|
JP Z,CONTROLUP ; CONTROL UP
|
|
LD A,0 ; NOTHING CAPTURED SO SEND BACK A ZERO
|
|
RET
|
|
TWOBYTE:; ALREADY GOT EO SO GET THE NEXT CHARACTER
|
|
CALL KB_WAITBYTE
|
|
CP 0F0H ; SEE THE NOTES - KEYUP FOR E0 KEYS IS EO F0 NN NOT F0 EO!!
|
|
JP Z,TWOBYTEUP ;
|
|
CP 071H ; DELETE
|
|
JP Z,DELETEKEY ;
|
|
CP 05AH ; RETURN ON NUMBER PAD
|
|
JP Z,RETURNKEY ;
|
|
CP 072H ;
|
|
JP Z,DOWNARROW ;
|
|
CP 074H ;
|
|
JP Z,RIGHTARROW ;
|
|
CP 06BH ;
|
|
JP Z,LEFTARROW ;
|
|
CP 075H ;
|
|
JP Z,UPARROW ;
|
|
CP 070H ;
|
|
JP Z,INSERT ;
|
|
CP 07DH ;
|
|
JP Z,PAGEUP ;
|
|
CP 07AH ;
|
|
JP Z,PAGEDOWN ;
|
|
CP 06CH ;
|
|
JP Z,HOME ;
|
|
CP 069H ;
|
|
JP Z,END ;
|
|
LD A,0 ; RETURNS NOTHING
|
|
RET
|
|
TWOBYTEUP: ;EXPECT A BYTE AND IGNORE IT
|
|
CALL KB_WAITBYTE ;
|
|
LD A,0 ;
|
|
RET ;
|
|
HOME: ;
|
|
LD A,1BH ; ESC
|
|
CALL KB_ENQUEUE ; STORE ON KB QUEUE
|
|
LD A,'?' ; ?
|
|
CALL KB_ENQUEUE ; STORE ON KB QUEUE
|
|
LD A,'W' ; W
|
|
CALL KB_ENQUEUE ; STORE ON KB QUEUE
|
|
RET ;
|
|
END: ;
|
|
LD A,1BH ; ESC
|
|
CALL KB_ENQUEUE ; STORE ON KB QUEUE
|
|
LD A,'?' ; ?
|
|
CALL KB_ENQUEUE ; STORE ON KB QUEUE
|
|
LD A,'Q' ; Q
|
|
CALL KB_ENQUEUE ; STORE ON KB QUEUE
|
|
RET ;
|
|
DOWNARROW: ;
|
|
LD A,1BH ; ESC
|
|
CALL KB_ENQUEUE ; STORE ON KB QUEUE
|
|
LD A,'B' ; B
|
|
CALL KB_ENQUEUE ; STORE ON KB QUEUE
|
|
RET ;
|
|
RIGHTARROW: ;
|
|
LD A,1BH ; ESC
|
|
CALL KB_ENQUEUE ; STORE ON KB QUEUE
|
|
LD A,'C' ; C
|
|
CALL KB_ENQUEUE ; STORE ON KB QUEUE
|
|
RET ;
|
|
LEFTARROW: ;
|
|
LD A,1BH ; ESC
|
|
CALL KB_ENQUEUE ; STORE ON KB QUEUE
|
|
LD A,'D' ; D
|
|
CALL KB_ENQUEUE ; STORE ON KB QUEUE
|
|
RET ;
|
|
UPARROW: ;
|
|
LD A,1BH ; ESC
|
|
CALL KB_ENQUEUE ; STORE ON KB QUEUE
|
|
LD A,'A' ; A
|
|
CALL KB_ENQUEUE ; STORE ON KB QUEUE
|
|
RET ;
|
|
INSERT: ;
|
|
LD A,1BH ; ESC
|
|
CALL KB_ENQUEUE ; STORE ON KB QUEUE
|
|
LD A,'?' ; ?
|
|
CALL KB_ENQUEUE ; STORE ON KB QUEUE
|
|
LD A,'P' ; P
|
|
CALL KB_ENQUEUE ; STORE ON KB QUEUE
|
|
RET ;
|
|
PAGEUP: ;
|
|
LD A,1BH ; ESC
|
|
CALL KB_ENQUEUE ; STORE ON KB QUEUE
|
|
LD A,'?' ; ?
|
|
CALL KB_ENQUEUE ; STORE ON KB QUEUE
|
|
LD A,'Y' ; Y
|
|
CALL KB_ENQUEUE ; STORE ON KB QUEUE
|
|
RET ;
|
|
PAGEDOWN: ;
|
|
LD A,1BH ; ESC
|
|
CALL KB_ENQUEUE ; STORE ON KB QUEUE
|
|
LD A,'?' ; ?
|
|
CALL KB_ENQUEUE ; STORE ON KB QUEUE
|
|
LD A,'S' ; S
|
|
CALL KB_ENQUEUE ; STORE ON KB QUEUE
|
|
RET ;
|
|
CONTROLDOWN: ; SAME CODE AS SHIFTDOWN BUT DIFF LOCATION
|
|
LD A,0FFH ;
|
|
LD (CTRL),A ; CONTROL DOWN
|
|
LD A,0 ;
|
|
RET ;
|
|
CONTROLUP: ; CONTROL KEY UP SEE SHIFT FOR EXPLANATION
|
|
LD A,0 ;
|
|
LD (CTRL),A ;
|
|
LD A,0 ;
|
|
RET ;
|
|
RETURNKEY: ;
|
|
LD A,13 ;
|
|
CALL KB_ENQUEUE ; STORE ON KB QUEUE
|
|
RET ;
|
|
DELETEKEY: ;
|
|
LD A,07FH ; DELETE KEY VALUE THAT CP/M USES
|
|
CALL KB_ENQUEUE ; STORE ON KB QUEUE
|
|
RET ;
|
|
CAPSTOG: ;
|
|
LD A,(CAPSLOCK) ;
|
|
XOR 11111111B ; SWAP ALL THE BITS
|
|
LD (CAPSLOCK),A ;
|
|
LD A,0 ; RETURNS NOTHING
|
|
RET ;
|
|
SHIFTDOWN: ; SHIFT IS SPECIAL - HOLD IT DOWN AND IT AUTOREPEATS
|
|
; SO ONCE IT IS DOWN, TURN CAPS ON AND IGNORE ALL FURTHER SHIFTS
|
|
; ONLY AN F0+SHIFT TURNS CAPS LOCK OFF AGAIN
|
|
LD A,0FFH ;
|
|
LD (CAPSLOCK),A ;
|
|
LD A,0 ; RETURNS NOTHING
|
|
RET ;
|
|
SHIFTUP: ; SHIFTUP TURNS OFF CAPS LOCK DEFINITELY
|
|
LD A,0 ;
|
|
LD (CAPSLOCK),A ;
|
|
LD A,0 ; RETURNS NOTHING
|
|
RET ;
|
|
|
|
;__KB_ENQUEUE______________________________________________________________________________________
|
|
;
|
|
; STORE A BYTE IN THE KEYBOARD QUEUE
|
|
; A: BYTE TO ENQUEUE
|
|
;__________________________________________________________________________________________________
|
|
KB_ENQUEUE:
|
|
PUSH DE ; STORE DE
|
|
PUSH HL ; STORE HL
|
|
PUSH AF ; STORE VALUE
|
|
LD A,(KB_QUEUE_PTR); PUT QUEUE POINTER IN A
|
|
CP 15 ; IS QUEUE FULL
|
|
JP P,KB_ENQUEUE_AB ; YES, ABORT
|
|
LD HL,KB_QUEUE ; GET QUEUE POINTER
|
|
PUSH HL ; MOVE HL TO BC
|
|
POP BC ;
|
|
LD H,0 ; ZERO OUT H
|
|
LD L,A ; PLACE QUEUE POINTER IN L
|
|
ADD HL,BC ; POINT HL AT THE NEXT LOACTION TO ADD VALUE
|
|
POP AF ; RESTORE VALUE
|
|
LD (HL),A ; ENQUEUE VALUE
|
|
LD A,(KB_QUEUE_PTR); GET QUEUE POINTER
|
|
INC A ; INC IT
|
|
LD (KB_QUEUE_PTR),A ;STORE QUEUE POINTER
|
|
KB_ENQUEUE_AB:
|
|
POP HL ; RESTORE HL
|
|
POP DE ; RESTORE DE
|
|
RET
|
|
|
|
|
|
;__KB_WAITBYTE_____________________________________________________________________________________
|
|
;
|
|
; WAIT FOR A BYTE - TESTS A NUMBER OF TIMES IF THERE IS A KEYBOARD INPUT,
|
|
; OVERWRITES ALL REGISTERS, RETURNS BYTE IN A
|
|
;__________________________________________________________________________________________________
|
|
KB_WAITBYTE:
|
|
CALL KB_CLOCKHIGH ; TURN ON KEYBOARD
|
|
LD HL,500 ; NUMBER OF TIMES TO CHECK 200=SLOW TYPE
|
|
; 10=ERROR, 25 ?ERROR 50 OK -
|
|
; THIS DELAY HAS TO BE THERE OTHERWISE WEIRD KEYUP ERRORS
|
|
WB1: PUSH HL ; STORE COUNTER
|
|
CALL KB_READBITS ; TEST FOR A LOW ON THE CLOCK LINE
|
|
POP HL ; GET THE COUNTER BACK
|
|
CP 0 ; TEST FOR A ZERO BACK FROM READBITS
|
|
JR NZ,WB2 ; IF NOT A ZERO THEN MUST HAVE A BYTE IE A KEYBOARD PRESS
|
|
LD DE,1 ; LOAD WITH 1
|
|
SBC HL,DE ; SUBTRACT 1
|
|
JR NZ,WB1 ; LOOP WAITING FOR A RESPONSE
|
|
WB2: PUSH AF ; STORE THE VALUE IN A
|
|
CALL KB_CLOCKLOW ; TURN OFF KEYBOARD
|
|
POP AF ; GET BACK BYTE AS CLOCKLOW ERASED IT
|
|
RET
|
|
|
|
;__KB_READBITS_____________________________________________________________________________________
|
|
;
|
|
; READBITS READS 11 BITS IN FROM THE KEYBOARD
|
|
; FIRST BIT IS A START BIT THEN 8 BITS FOR THE BYTE
|
|
; THEN A PARITY BIT AND A STOP BIT
|
|
; RETURNS AFTER ONE MACHINE CYCLE IF NOT LOW
|
|
; USES A, B,D, E
|
|
; RETURNS A=0 IF NO DATA, A= SCANCODE (OR PART THEREOF)
|
|
;__________________________________________________________________________________________________
|
|
KB_READBITS:
|
|
IN A,(VPPIB)
|
|
BIT 1,A ; TEST THE CLOCK BIT
|
|
JR Z,R1 ; IF LOW THEN START THE CAPTURE
|
|
LD A,0 ; RETURNS A=0 IF NOTHING
|
|
RET ;
|
|
R1: CALL KB_WAITCLOCKHIGH; IF GETS TO HERE THEN MUST BE LOW SO WAIT TILL HIGH
|
|
LD B,8 ; SAMPLE 8 TIMES
|
|
LD E,0 ; START WITH E=0
|
|
R2: LD D,B ; STORE BECAUSE WAITCLOCKHIGH DESTROYS
|
|
CALL KB_WAITCLOCKLOW ; WAIT TILL CLOCK GOES LOW
|
|
IN A,(VPPIB) ; SAMPLE THE DATA LINE
|
|
RRA ; MOVE THE DATA BIT INTO THE CARRY REGISTER
|
|
LD A,E ; GET THE BYTE WE ARE BUILDING IN E
|
|
RRA ; MOVE THE CARRY BIT INTO BIT 7 AND SHIFT RIGHT
|
|
LD E,A ; STORE IT BACK AFTER 8 CYCLES 1ST BIT READ WILL BE IN B0
|
|
CALL KB_WAITCLOCKHIGH; WAIT TILL GOES HIGH
|
|
LD B,D ; RESTORE FOR LOOP
|
|
DJNZ R2 ; DO THIS 8 TIMES
|
|
CALL KB_WAITCLOCKLOW ; GET THE PARITY BIT
|
|
CALL KB_WAITCLOCKHIGH;
|
|
CALL KB_WAITCLOCKLOW ; GET THE STOP BIT
|
|
CALL KB_WAITCLOCKHIGH;
|
|
LD A,E ; RETURNS WITH ANSWER IN A
|
|
RET
|
|
|
|
NORMALKEYS:
|
|
; THE TI CHARACTER CODES, OFFSET FROM LABEL BY KEYBOARD SCAN CODE
|
|
.DB $00, $00, $00, $00, $00, $00, $00, $00
|
|
.DB $00, $00, $00, $00, $00, $09, "`", $00 ; $09=TAB
|
|
.DB $00, $00, $00, $00, $00, "q", "1", $00
|
|
.DB $00, $00, "z", "s", "a", "w", "2", $00
|
|
.DB $00, "c", "x", "d", "e", "4", "3", $00
|
|
.DB $00, " ", "v", "f", "t", "r", "5", $00
|
|
.DB $00, "n", "b", "h", "g", "y", "6", $00
|
|
.DB $00, $00, "m", "j", "u", "7", "8", $00
|
|
.DB $00, ",", "k", "i", "o", "0", "9", $00
|
|
.DB $00, ".", "/", "l", ";", "p", "-", $00
|
|
.DB $00, $00, $27, $00, "[", "=", $00, $00 ; $27=APOSTROPHE
|
|
.DB $00, $00, $00, "]", $00, $5C, $00, $00 ; $5C=BACKSLASH
|
|
.DB $00, $00, $00, $00, $00, $00, $00, $00
|
|
.DB $00, "1", $00, "4", "7", $00, $00, $00
|
|
.DB "0", ".", "2", "5", "6", "8", $00, $00
|
|
.DB $00, "+", "3", "-", "*", "9", $00, $00
|
|
|
|
SHIFTKEYS:
|
|
.DB $00, $00, $00, $00, $00, $00, $00, $00
|
|
.DB $00, $00, $00, $00, $00, 009, "~", $00 ; $09=TAB
|
|
.DB $00, $00, $00, $00, $00, "Q", "!", $00
|
|
.DB $00, $00, "Z", "S", "A", "W", "@", $00
|
|
.DB $00, "C", "X", "D", "E", "$", "#", $00
|
|
.DB $00, " ", "V", "F", "T", "R", "%", $00
|
|
.DB $00, "N", "B", "H", "G", "Y", "^", $00
|
|
.DB $00, $00, "M", "J", "U", "&", "*", $00
|
|
.DB $00, "<", "K", "I", "O", ")", "(", $00
|
|
.DB $00, ">", "?", "L", ":", "P", "_", $00
|
|
.DB $00, $00, 034, $00, "{", "+", $00, $00 ; $22=DBLQUOTE
|
|
.DB $00, $00, $00, "}", $00, "|", $00, $00
|
|
.DB $00, $00, $00, $00, $00, $00, $00, $00
|
|
.DB $00, "1", $00, "4", "7", $00, $00, $00
|
|
.DB "0", ".", "2", "5", "6", "8", $00, $00
|
|
.DB $00, "+", "3", "-", "*", "9", $00, $00
|
|
;
|
|
;==================================================================================================
|
|
; VDU DRIVER - DATA
|
|
;==================================================================================================
|
|
;
|
|
ALT_KEYPAD .DB 0 ; ALT KEYPAD ENABLED?
|
|
GR_MODE .DB 0 ; GRAPHICS MODE ENABLED?
|
|
TERM_X .DB 0 ; CURSOR X
|
|
TERM_Y .DB 0 ; CURSOR Y
|
|
TERMSTATE .DB 0 ; TERMINAL STATE
|
|
; 0 = NORMAL
|
|
; 1 = ESC RCVD
|
|
VDU_DISPLAYPOS .DW 0 ; CURRENT DISPLAY POSITION
|
|
VDU_DISPLAY_START .DW 0 ; CURRENT DISPLAY POSITION
|
|
CAPSLOCK .DB 0 ; location for caps lock, either 00000000 or 11111111
|
|
CTRL .DB 0 ; location for ctrl on or off 00000000 or 11111111
|
|
NUMLOCK .DB 0 ; location for num lock
|
|
SKIPCOUNT .DB 0 ; only check some calls, speeds up a lot of cp/m
|
|
KB_QUEUE .FILL 16,0 ; 16 BYTE KB QUEUE
|
|
KB_QUEUE_PTR .DB 0 ; POINTER TO QUEUE
|
|
|