;__VDUDRIVER_______________________________________________________________________________________ ; ; VDUDRIVER FOR CBIOS 2.2, PAGED. ; ; VDU DRIVERS BY: ANDREW LYNCH ; KEYBOARD DRIVERS BY: DR JAMES MOXHAM ; REMAINDER WRITTEN BY: DAN WERNER -- 11/7/2009 ;__________________________________________________________________________________________________ ; ;__________________________________________________________________________________________________ ; DATA CONSTANTS ;__________________________________________________________________________________________________ ; READR .EQU 0F0h ; READ VDU WRITR .EQU 0F1h ; WRITE VDU SY6545S .EQU 0F2h ; VDU STATUS/REGISTER SY6545D .EQU 0F3h ; STATE_NORMAL .EQU 00H ; NORMAL TERMINAL OPS STATE_ESC .EQU 01H ; ESC MODE STATE_DIR_L .EQU 02H ; ESC-Y X * STATE_DIR_C .EQU 03H ; ESC-Y * X ESC_KEY .EQU 1BH ; ESCAPE CODE ; ;__________________________________________________________________________________________________ ; BOARD INITIALIZATION ;__________________________________________________________________________________________________ ; VDU_INIT: CALL INITVDU CALL PPK_INIT XOR A RET ; ;__________________________________________________________________________________________________ ; FUNCTION JUMP TABLE ;__________________________________________________________________________________________________ ; VDU_DISPCIO: LD A,B ; GET REQUESTED FUNCTION AND $0F ; ISOLATE SUB-FUNCTION JR Z,VDU_CIOIN DEC A JR Z,VDU_CIOOUT DEC A JR Z,VDU_CIOIST DEC A JR Z,VDU_CIOOST CALL PANIC ; VDU_CIOIN: JP PPK_READ ; VDU_CIOIST: JP PPK_STAT ; VDU_CIOOUT: JP VDU_VDAWRC ; VDU_CIOOST: XOR A INC A RET ; ;__________________________________________________________________________________________________ ; NEW FUNCTION JUMP TABLE ;__________________________________________________________________________________________________ ; VDU_DISPVDA: LD A,B ; GET REQUESTED FUNCTION AND $0F ; ISOLATE SUB-FUNCTION JR Z,VDU_VDAINI DEC A JR Z,VDU_VDAQRY DEC A JR Z,VDU_VDARES DEC A JR Z,VDU_VDASCS DEC A JR Z,VDU_VDASCP DEC A JR Z,VDU_VDASAT DEC A JR Z,VDU_VDASCO DEC A JR Z,VDU_VDAWRC DEC A JR Z,VDU_VDAFIL DEC A JR Z,VDU_VDASCR DEC A JP Z,PPK_STAT DEC A JP Z,PPK_FLUSH DEC A JP Z,PPK_READ CALL PANIC VDU_VDAINI: CALL INITVDU XOR A RET VDU_VDAQRY: CALL PANIC VDU_VDARES: JR VDU_INIT VDU_VDASCS: CALL PANIC VDU_VDASCP: LD A,E LD (TERM_X),A LD A,D LD (TERM_Y),A CALL GOTO_XY XOR A RET VDU_VDASAT: ; FIX: NOT IMPLEMENTED!!! CALL PANIC VDU_VDASCO: ; NOT SUPPORTED!!! CALL PANIC VDU_VDAWRC: ; PUSH CHARACTER OUT AT CURRENT POSITION LD A,31 ; PREP VDU FOR DATA R/W OUT (SY6545S),A CALL VDU_WAITRDY ; WAIT FOR VDU TO BE READY LD A,E OUT (WRITR),A ; OUTPUT CHAR TO VDU ; UPDATE CURSOR POSITION TO FOLLOW CHARACTERS LD HL,(VDU_DISPLAYPOS) ; GET CURRENT DISPLAY POSITION INC HL ; INCREMENT IT LD (VDU_DISPLAYPOS),HL ; STORE NEW DISPLAY POSITION LD DE,(VDU_DISPLAY_START) ; GET DISPLAY START ADD HL,DE ; ADD IT TO DISPLAY POSITION LD A,14 ; UPDATE CURSOR POSITION CALL VDU_HL2WREG_A ; SEND IT ; RETURN WITH SUCCESS XOR A RET VDU_VDAFIL: LD A, 31 ; PREP VDU FOR DATA R/W OUT (SY6545S),A VDU_VDAFIL1: LD A,H ; CHECK NUMBER OF FILL CHARS LEFT OR L JR Z,VDU_VDAFIL2 ; ALL DONE, GO TO COMPLETION CALL VDU_WAITRDY ; WAIT FOR VDU TO BE READY LD A,E OUT (WRITR), A ; OUTPUT CHAR TO VDU DEC HL ; DECREMENT COUNT JR VDU_VDAFIL1 ; LOOP AS NEEDED VDU_VDAFIL2: CALL GOTO_XY ; YES, MOVE CURSOR BACK TO ORIGINAL POSITION XOR A ; RESULT = 0 RET VDU_VDASCR: ; FIX: IMPLEMENT REVERSE SCROLLING!!! LD A,E OR A RET Z PUSH DE CALL DO_SCROLL POP DE DEC E JR VDU_VDASCR ; VDU_WAITRDY: IN A,(SY6545S) ; READ STATUS OR A ; SET FLAGS RET M ; IF BIT 7 SET, THEN READY! JR VDU_WAITRDY ; KEEP CHECKING ;__________________________________________________________________________________________________ ; IMBED COMMON PARALLEL PORT KEYBOARD DRIVER ;__________________________________________________________________________________________________ ; #INCLUDE "ppk.asm" ; ;__________________________________________________________________________________________________ ; INITIALIZATION ;__________________________________________________________________________________________________ INITVDU: CALL VDUINIT ; INIT VDU ; CALL KB_INITIALIZE ; INIT KB ; CALL PR_INITIALIZE ; INIT PR ; CALL DSPMATRIX ; DISPLAY INIT MATRIX SCREEN ; CALL WAIT_KBHIT ; WAIT FOR A KEYSTROKE ; LD A,0 ; EMPTY KB QUEUE ; LD (KB_QUEUE_PTR),A ; CALL PERF_ERASE_EOS ; CLEAR SCREEN CALL PERF_CURSOR_HOME ; CURSOR HOME RET ; ;__CHARIN__________________________________________________________________________________________ ; ; PROCESS INCOMMING CHARACTER AND DISPLAY ON SCREEN OR PERFORM FUNCTION ; C: INCOMMING CHARACTER ;__________________________________________________________________________________________________ CHARIN: LD A,C PUSH AF ; STORE AF LD A,(TERMSTATE) ; MOVE CURRENT STATE INTO A CP STATE_NORMAL ; NORMAL PROCESSING STATE? JP Z,CHARIN_NORM ; CP STATE_ESC ; ESCAPE PROCESSING STATE? JP Z,CHARIN_ESCSTATE ; CP STATE_DIR_L ; WAITING FOR Y COORD STATE? JP Z,CHARIN_DIR_L_STATE ; CP STATE_DIR_C ; WAITING FOR X COORD STATE? JP Z,CHARIN_DIR_C_STATE ; LD A,STATE_NORMAL ; UNKNOWN STATE, RESET STATE LD (TERMSTATE),A ; POP AF ; RET ; ;__CHARIN_DIR_L_STATE______________________________________________________________________________ ; ; PROCESS "WAITING FOR Y COORD STATE" ;__________________________________________________________________________________________________ CHARIN_DIR_L_STATE: LD A,32 ; MOVE 32 (' ') INTO A LD C,A ; PARK INTO C POP AF ; GET CHAR FROM STACK SUB C ; DECODE CHAR INTO USABLE Y COORD CP 24 ; IS OFF SCREEN? JP M,CHARIN_DIR_L_STATE_CONT LD A,23 ; YES, PLACE CRSR ON LAST ROW CHARIN_DIR_L_STATE_CONT: LD (TERM_Y),A ; NO, USE DECODED VALUE LD A,STATE_DIR_C ; SET UP STATE TO GET X COORD LD (TERMSTATE),A ; RET ;__CHARIN_DIR_C_STATE______________________________________________________________________________ ; ; PROCESS "WAITING FOR X COORD STATE" ;__________________________________________________________________________________________________ CHARIN_DIR_C_STATE: LD A,32 ; MOVE 32 (' ') INTO A LD C,A ; PARK INTO C POP AF ; GET CHAR FROM STACK SUB C ; DECODE CHAR INTO USABLE X COORD CP 80 ; IS OFF SCREEN? JP M,CHARIN_DIR_C_STATE_CONT LD A,79 ; YES, PLACE CRSR IN LAST COLUMN CHARIN_DIR_C_STATE_CONT: LD (TERM_X),A ; NO, USE DECODED VALUE CALL GOTO_XY ; SET CURSOR POS LD A,STATE_NORMAL ; RESET STATE TO NORMAL LD (TERMSTATE),A ; RET ;__CHARIN_NORM_____________________________________________________________________________________ ; ; PROCESS NORMAL STATE ;__________________________________________________________________________________________________ CHARIN_NORM: POP AF ; GET CHAR FROM STACK CP 0AH ; IS LINEFEED? JP Z,CHARIN_LF ; CP 09H ; IS TAB? JP Z,CHARIN_TAB ; CP 08H ; IS BS? JP Z,CHARIN_BS ; CP 0DH ; IS CR? JP Z,CHARIN_CR ; CP 07H ; IS BELL? JP Z,CHARIN_BELL ; CP 13H ; IS XOFF? JP Z,CHARIN_XOFF ; CP 11H ; IS XON? JP Z,CHARIN_XON ; CP ESC_KEY ; IS ESC? JP Z,CHARIN_ESC ; JP VDU_PUTCHAR ; NORMAL OUTPUT CHAR ;__CHARIN_ESC______________________________________________________________________________________ ; ; PROCESS "ESC" STATE ;__________________________________________________________________________________________________ CHARIN_ESC: LD A,STATE_ESC ; ESC PRESSED, STATE TO ESCPRESSED LD (TERMSTATE),A ; RET ;__CHARIN_LF_______________________________________________________________________________________ ; ; PROCESS LINE FEED ;__________________________________________________________________________________________________ CHARIN_LF: LD A,(TERM_Y) ; MOVE CRSR Y COORD INTO A INC A ; INC A LD (TERM_Y),A ; STORE NEW Y COORD JP GOTO_XY ; SET CRSR POSITION ;__CHARIN_TAB______________________________________________________________________________________ ; ; PROCESS TABS ;__________________________________________________________________________________________________ CHARIN_TAB: LD HL,TABSTOPS ; SET HL TO TAB STOP TABLE LD A,(TERM_X) ; MOVE CURENT CRSR X COORD INTO A INC A ; INC A LD C,A ; STORE CRSR X COORD INTO A CHARIN_TAB_LOOP: LD A,(HL) ; GET NEXT TAB STOP OR A ; IS ZERO? JP Z,CHARIN_TAB_EXIT ; END OF TABLE, PROCESS 73+ INC HL ; SET POINTER TO NEXT TABLE ENTRY CP C ; IS CURRENT ENTRY > X COORD? JP M,CHARIN_TAB_LOOP ; NO, LOOP LD (TERM_X),A ; YES, USE IT JP GOTO_XY ; SET CRSR POSITION CHARIN_TAB_EXIT: LD A,(TERM_X) ; COLUMN IS PAST LAST TAB STOP, SET A TO CRSR POS CP 79 ; IS LAST PHYSICAL POS? RET Z ; YES, DO NOTHING INC A ; NO, INC CRSR BY ONE LD (TERM_X),A ; STORE NEW X COORD JP GOTO_XY ; SET CRSR POSITION TABSTOPS: .DB 09,17,25,33,41,49,57,65,73,00 ;__CHARIN_BS_______________________________________________________________________________________ ; ; PROCESS BACKSPACE ;__________________________________________________________________________________________________ CHARIN_BS: JP PERF_CURSOR_LEFT ; PERFORM CRSR LEFT FUNCTION ;__CHARIN_CR_______________________________________________________________________________________ ; ; PROCESS CARRAGE RETURN ;__________________________________________________________________________________________________ CHARIN_CR: LD A,00H ; MOVE 0 TO X COORD LD (TERM_X),A ; JP GOTO_XY ; GOTO XY COORDS ;__CHARIN_BELL_____________________________________________________________________________________ ; ; PROCESS BELL ;__________________________________________________________________________________________________ CHARIN_BELL: ; ; NO HARDWARE FOR THIS, DO NOTHING ; RET ;__CHARIN_XOFF_____________________________________________________________________________________ ; ; PROCESS XOFF ;__________________________________________________________________________________________________ CHARIN_XOFF: ; ; SHOULD NOT BE NECESSARY FOR LOCAL IMPLIMENTATION ; RET ;__CHARIN_XON______________________________________________________________________________________ ; ; PROCESS XON ;__________________________________________________________________________________________________ CHARIN_XON: ; ; SHOULD NOT BE NECESSARY FOR LOCAL IMPLIMENTATION ; RET ;__CHARIN_ESCSTATE_________________________________________________________________________________ ; ; PROCESS ESC STATE ;__________________________________________________________________________________________________ CHARIN_ESCSTATE: POP AF ; CP 'A' ; IS CURSOR UP? JP Z, PERF_CURSOR_UP ; CP 'B' ; IS CURSOR DOWN? JP Z, PERF_CURSOR_DOWN ; CP 'C' ; IS CURSOR RIGHT? JP Z, PERF_CURSOR_RIGHT ; CP 'D' ; IS CURSOR LEFT? JP Z, PERF_CURSOR_LEFT ; CP 'F' ; IS ENTER GRAPHICS MODE? JP Z, PERF_ENTER_GR ; CP 'G' ; IS EXIT GRAPHICS MODE? JP Z, PERF_EXIT_GR ; CP 'H' ; IS CURSOR HOME? JP Z, PERF_CURSOR_HOME ; CP 'I' ; IS CURSOR HOME? JP Z, PERF_REVERSE_LF ; CP 'Y' ; IS REVERSE LINE FEED? JP Z, PERF_DIRECT_ADDRESS ; CP 'K' ; IS ERASE TO END OF LINE? JP Z,PERF_ERASE_EOL ; CP 'J' ; IS ERASE TO END OF SCREEN? JP Z,PERF_ERASE_EOS ; CP 'Z' ; IS TERMINAL IDENTIFY? JP Z,PERF_IDENTIFY ; CP '{' ; IS ENTER HOLD SCREEN MODE? JP Z,PERF_ENTER_HOLD ; CP 05CH ; IS EXIT HOLD SCREEN MODE? JP Z,PERF_EXIT_HOLD ; CP '=' ; IS ENTER ALT KEYPAD MODE? JP Z,PERF_ENTER_ALT ; CP '}' ; IS EXIT ALT KEYPAD MODE? JP Z,PERF_EXIT_ALT ; CALL VDU_PUTCHAR ; NORMAL OUTPUT CHAR JP SET_STATE_NORMAL ; ;__PERF_REVERSE_LF_________________________________________________________________________________ ; ; PERFORM REVERSE LINE FEED ;__________________________________________________________________________________________________ PERF_REVERSE_LF: CALL SET_STATE_NORMAL ; SET STATE TO NORMAL LD A,(TERM_Y) ; GET CURRENT Y COORD INTO A OR A ; IS ZERO JP Z,REVERSE_SCROLL ; YES, SCROLL SCREEN DOWN ONE LINE DEC A ; NO, MOVE CRSR UP ONE LINE LD (TERM_Y),A ; STORE NEW CRSR POSITION JP GOTO_XY ; POSITION CRSR ;__PERF_DIRECT_ADDRESS_____________________________________________________________________________ ; ; PERFORM DIRECT CURSOR ADDRESSING ;__________________________________________________________________________________________________ PERF_DIRECT_ADDRESS: LD A,STATE_DIR_L ; SET STATE "WAITING FOR Y COORD" LD (TERMSTATE),A ; RET ; ;__PERF_ENTER_GR___________________________________________________________________________________ ; ; PERFORM ENTER GRAPHICS MODE ;__________________________________________________________________________________________________ PERF_ENTER_GR: LD A,0FFH ; LD (GR_MODE),A ; GRAPHICS MODE JP SET_STATE_NORMAL ; ;__PERF_EXIT_GR____________________________________________________________________________________ ; ; PERFORM EXIT GRAPHICS MODE ;__________________________________________________________________________________________________ PERF_EXIT_GR: LD A,00FH ; LD (GR_MODE),A ; GRAPHICS MODE JP SET_STATE_NORMAL ; ;__PERF_ENTER_ALT___________________________________________________________________________________ ; ; PERFORM ENTER ALTERNATE KEYPAD MODE ;__________________________________________________________________________________________________ PERF_ENTER_ALT: LD A,0FFH ; LD (ALT_KEYPAD),A ; ALT KEYPAD JP SET_STATE_NORMAL ; ;__PERF_EXIT_ALT___________________________________________________________________________________ ; ; PERFORM EXIT ALTERNATE KEYPAD MODE ;__________________________________________________________________________________________________ PERF_EXIT_ALT: LD A,00H ; LD (ALT_KEYPAD),A ; ALT KEYPAD JP SET_STATE_NORMAL ; ;__PERF_ENTER_HOLD_________________________________________________________________________________ ; ; PERFORM ENTER HOLD MODE ;__________________________________________________________________________________________________ PERF_ENTER_HOLD: ; ********* IGNORE HOLD MODE !! JP SET_STATE_NORMAL ; ;__PERF_EXIT_HOLD__________________________________________________________________________________ ; ; PERFORM EXIT HOLD MODE ;__________________________________________________________________________________________________ PERF_EXIT_HOLD: ; ********* IGNORE HOLD MODE !! JP SET_STATE_NORMAL ; ;__SET_STATE_NORMAL________________________________________________________________________________ ; ; SET NORMAL STATE ;__________________________________________________________________________________________________ SET_STATE_NORMAL: LD A,STATE_NORMAL ; RESET STATE LD (TERMSTATE),A ; RET ;__PERF_ERASE_EOL__________________________________________________________________________________ ; ; PERFORM ERASE FROM CURSOR POS TO END OF LINE ;__________________________________________________________________________________________________ PERF_ERASE_EOL: LD A,(TERM_X) ; GET CURRENT CURSOR X COORD LD C,A ; STORE IT IN C LD A,80 ; MOVE CURRENT LINE WIDTH INTO A SUB C ; GET REMAINING POSITIONS ON CURRENT LINE LD B,A ; MOVE IT INTO B LD A, 31 ; UPDATE TOGGLE VDU CHIP OUT (SY6545S),A ; PERF_ERASE_EOL_LOOP: CALL VDU_UPDATECHECK ; WAIT FOR VDU CHIP TO BE READY LD A,32 ; MOVE SPACE CHARACTER INTO A OUT (WRITR),A ; WRITE IT TO SCREEN, VDU WILL AUTO INC TO NEXT ADDRESS DJNZ PERF_ERASE_EOL_LOOP ; LOOP UNTIL DONE CALL GOTO_XY ; MOVE CURSOR BACK TO ORIGINAL POSITION CALL SET_STATE_NORMAL ; SET NORMAL STATE RET ;__PERF_ERASE_EOS__________________________________________________________________________________ ; ; PERFORM ERASE FROM CURSOR POS TO END OF SCREEN ;__________________________________________________________________________________________________ PERF_ERASE_EOS: LD HL,0780H ; SET SCREEN SIZE INTO HL PUSH HL ; MOVE IT TO DE POP DE ; LD A, 31 ; UPDATE TOGGLE VDU CHIP OUT (SY6545S),A ; PERF_ERASE_EOS_LOOP: CALL VDU_UPDATECHECK ; WAIT FOR VDU CHIP TO BE READY LD A, ' ' ; MOVE SPACE CHARACTER INTO A OUT (WRITR),A ; WRITE IT TO SCREEN, VDU WILL AUTO INC TO NEXT ADDRESS DEC DE ; DEC COUNTER LD A,D ; IS COUNTER 0 YET? OR E ; JP NZ,PERF_ERASE_EOS_LOOP ; NO, LOOP CALL GOTO_XY ; YES, MOVE CURSOR BACK TO ORIGINAL POSITION CALL SET_STATE_NORMAL ; SET NORMAL STATE RET ;__PERF_IDENTIFY___________________________________________________________________________________ ; ; PERFORM TERMINAL IDENTIFY FUNCTION ;__________________________________________________________________________________________________ PERF_IDENTIFY: ; LD A,ESC_KEY ; ; CALL KB_ENQUEUE ; STORE ON KB QUEUE ; LD A,'/' ; ; CALL KB_ENQUEUE ; STORE ON KB QUEUE ; LD A,'K' ; ; CALL KB_ENQUEUE ; STORE ON KB QUEUE CALL SET_STATE_NORMAL ; SET NORMAL STATE RET ;__PERF_CURSOR_HOME________________________________________________________________________________ ; ; PERFORM CURSOR HOME ;__________________________________________________________________________________________________ PERF_CURSOR_HOME: LD A,0 ; LOAD 0 INTO A LD (TERM_X),A ; SET X COORD LD (TERM_Y),A ; SET Y COORD CALL SET_STATE_NORMAL ; SET NORMAL STATE JP GOTO_XY ; MOVE CURSOR TO POSITION ;__PERF_CURSOR_LEFT________________________________________________________________________________ ; ; PERFORM CURSOR LEFT ;__________________________________________________________________________________________________ PERF_CURSOR_LEFT: LD A,(TERM_X) ; GET CURRENT X COORD INTO A OR A ; IS ZERO? JP Z,PERF_CURSOR_ABORT ; YES, ABORT DEC A ; MOVE ONE TO THE LEFT LD (TERM_X),A ; STORE NEW CURSOR POSITION CALL SET_STATE_NORMAL ; SET NORMAL STATE JP GOTO_XY ; MOVE CURSOR TO POSITION ;__PERF_CURSOR_RIGHT_______________________________________________________________________________ ; ; PERFORM CURSOR RIGHT ;__________________________________________________________________________________________________ PERF_CURSOR_RIGHT: LD A,(TERM_X) ; GET CURRENT X COORD INTO A CP 79 ; IS END OF LINE? JP Z,PERF_CURSOR_ABORT ; YES, ABORT INC A ; MOVE ONE TO THE RIGHT LD (TERM_X),A ; STORE NEW CURSOR POSITION CALL SET_STATE_NORMAL ; SET NORMAL STATE JP GOTO_XY ; MOVE CURSOR TO POSITION ;__PERF_CURSOR_UP__________________________________________________________________________________ ; ; PERFORM CURSOR UP ;__________________________________________________________________________________________________ PERF_CURSOR_UP: LD A,(TERM_Y) ; GET CURRENT Y COORD INTO A OR A ; IS ZERO? JP Z,PERF_CURSOR_ABORT ; YES, ABORT DEC A ; MOVE UP ONE POSITION LD (TERM_Y),A ; STORE NEW CURSOR POSITION 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 ; ;__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 01AH ; 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 ; ;================================================================================================== ; 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