mirror of https://github.com/wwarthen/RomWBW.git
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
497 lines
14 KiB
497 lines
14 KiB
;======================================================================
|
|
; VIDEO DRIVER FOR FPGA VGA
|
|
; http://s100computers.com/My%20System%20Pages/FPGA%20Z80%20SBC/FPGA%20Z80%20SBC.htm
|
|
;
|
|
; WRITTEN BY: WAYNE WARTHEN -- 9/2/2024
|
|
;======================================================================
|
|
;
|
|
; FPGA VGA EXPOSES A FRAME BUFFER STARTING AT $E000.
|
|
; PORT $08 CONTROLS ACCESS TO THE FRAME BUFFER.
|
|
; - WHEN $01, FRAME BUFFER APPEARS AT $E000 IN CPU ADDRESS SPACE
|
|
; - WHEN $00, FRAME BUFFER IS INACCESSIBLE BY CPU
|
|
; PORT $C0: SET/GET CURSOR COL
|
|
; PORT $C1: SET/GET CURSOR ROW
|
|
; PORT $C2: CONTROLS VGA OUTPUT
|
|
; BIT 0: BLUE
|
|
; BIT 1: GREEN
|
|
; BIT 2: RED
|
|
; BIT 3: UNUSED?
|
|
; BIT 4: CURSOR MODE
|
|
; BIT 5: CURSOR BLINK
|
|
; BIT 6: CURSOR ENABLE
|
|
; BIT 7: VGA SIGNAL OUTPUT ENABLE
|
|
; PORT $08: BUFFER SELECT, 1=SELECTED
|
|
;
|
|
; TODO:
|
|
;
|
|
;======================================================================
|
|
; FPGA VGA DRIVER - CONSTANTS
|
|
;======================================================================
|
|
;
|
|
FV_FBUF .EQU $E000 ; ADDRESS OF FRAME BUFFER
|
|
FV_BASE .EQU $C0 ; BASE I/O ADDRESS
|
|
FV_CCOL .EQU FV_BASE+0 ; CUR COL PORT
|
|
FV_CROW .EQU FV_BASE+1 ; CUR ROW PORT
|
|
FV_CTL .EQU FV_BASE+2 ; VGA CONTROL PORT
|
|
;
|
|
FV_BUFCTL .EQU $08
|
|
;
|
|
FV_KBDDATA .EQU $03 ; KBD CTLR DATA PORT
|
|
FV_KBDST .EQU $02 ; KBD CTLR STATUS/CMD PORT
|
|
;
|
|
FV_ROWS .EQU 40
|
|
FV_COLS .EQU 80
|
|
;
|
|
TERMENABLE .SET TRUE ; INCLUDE TERMINAL PSEUDODEVICE DRIVER
|
|
;;;KBDENABLE .SET TRUE ; INCLUDE KBD KEYBOARD SUPPORT
|
|
;
|
|
DEVECHO "FV: IO="
|
|
DEVECHO FV_BASE
|
|
DEVECHO ", KBD MODE=FV"
|
|
DEVECHO ", KBD IO="
|
|
DEVECHO FV_KBDDATA
|
|
DEVECHO "\n"
|
|
;
|
|
;======================================================================
|
|
; FPGA VGA DRIVER - INITIALIZATION
|
|
;======================================================================
|
|
;
|
|
FV_INIT:
|
|
LD IY,FV_IDAT ; POINTER TO INSTANCE DATA
|
|
;
|
|
CALL NEWLINE ; FORMATTING
|
|
PRTS("FV: IO=0x$")
|
|
LD A,FV_BASE
|
|
CALL PRTHEXBYTE
|
|
CALL FV_PROBE ; CHECK FOR HW PRESENCE
|
|
JR Z,FV_INIT1 ; CONTINUE IF HW PRESENT
|
|
;
|
|
; HARDWARE NOT PRESENT
|
|
PRTS(" NOT PRESENT$")
|
|
OR $FF ; SIGNAL FAILURE
|
|
RET
|
|
;
|
|
FV_INIT1:
|
|
; RECORD DRIVER ACTIVE
|
|
OR $FF
|
|
LD (FV_ACTIVE),A
|
|
; DISPLAY CONSOLE DIMENSIONS
|
|
LD A,FV_COLS
|
|
CALL PC_SPACE
|
|
CALL PRTDECB
|
|
LD A,'X'
|
|
CALL COUT
|
|
LD A,FV_ROWS
|
|
CALL PRTDECB
|
|
PRTS(" TEXT$")
|
|
|
|
; HARDWARE INITIALIZATION
|
|
CALL FV_CRTINIT ; SETUP THE FPGA VGA CHIP REGISTERS
|
|
CALL FV_VDAINI ; INITIALIZE
|
|
;CALL KBD_INIT ; INITIALIZE KEYBOARD DRIVER
|
|
|
|
; ADD OURSELVES TO VDA DISPATCH TABLE
|
|
LD BC,FV_FNTBL ; BC := FUNCTION TABLE ADDRESS
|
|
LD DE,FV_IDAT ; DE := FPGA VGA INSTANCE DATA PTR
|
|
CALL VDA_ADDENT ; ADD ENTRY, A := UNIT ASSIGNED
|
|
|
|
; INITIALIZE EMULATION
|
|
LD C,A ; C := ASSIGNED VIDEO DEVICE NUM
|
|
LD DE,FV_FNTBL ; DE := FUNCTION TABLE ADDRESS
|
|
LD HL,FV_IDAT ; HL := FPGA VGA INSTANCE DATA PTR
|
|
CALL TERM_ATTACH ; DO IT
|
|
|
|
XOR A ; SIGNAL SUCCESS
|
|
RET
|
|
;
|
|
;======================================================================
|
|
; FPGA VGA DRIVER - VIDEO DISPLAY ADAPTER (VDA) FUNCTIONS
|
|
;======================================================================
|
|
;
|
|
FV_FNTBL:
|
|
.DW FV_VDAINI
|
|
.DW FV_VDAQRY
|
|
.DW FV_VDARES
|
|
.DW FV_VDADEV
|
|
.DW FV_VDASCS
|
|
.DW FV_VDASCP
|
|
.DW FV_VDASAT
|
|
.DW FV_VDASCO
|
|
.DW FV_VDAWRC
|
|
.DW FV_VDAFIL
|
|
.DW FV_VDACPY
|
|
.DW FV_VDASCR
|
|
.DW FV_STAT
|
|
.DW FV_FLUSH
|
|
.DW FV_READ
|
|
.DW FV_VDARDC
|
|
#IF (($ - FV_FNTBL) != (VDA_FNCNT * 2))
|
|
.ECHO "*** INVALID FV FUNCTION TABLE ***\n"
|
|
!!!!!
|
|
#ENDIF
|
|
|
|
FV_VDAINI:
|
|
; RESET VDA
|
|
CALL FV_VDARES ; RESET VDA
|
|
LD HL,0 ; ZERO
|
|
LD (FV_POS),HL ; ... TO POSITION
|
|
LD A,' ' ; BLANK THE SCREEN
|
|
LD DE,FV_ROWS*FV_COLS ; FILL ENTIRE BUFFER
|
|
CALL FV_FILL ; DO IT
|
|
LD DE,0 ; ROW = 0, COL = 0
|
|
CALL FV_XY ; SEND CURSOR TO TOP LEFT
|
|
CALL FV_SHOWCUR ; NOW SHOW THE CURSOR
|
|
XOR A ; SIGNAL SUCCESS
|
|
RET
|
|
|
|
FV_VDAQRY:
|
|
LD C,$00 ; MODE ZERO IS ALL WE KNOW
|
|
LD D,FV_ROWS ; ROWS
|
|
LD E,FV_COLS ; COLS
|
|
LD HL,0 ; EXTRACTION OF CURRENT BITMAP DATA NOT SUPPORTED
|
|
XOR A ; SIGNAL SUCCESS
|
|
RET
|
|
|
|
FV_VDARES:
|
|
CALL FV_CRTINIT
|
|
XOR A ; SIGNAL SUCCESS
|
|
RET
|
|
|
|
FV_VDADEV:
|
|
LD D,VDADEV_FV ; D := DEVICE TYPE
|
|
LD E,0 ; E := PHYSICAL UNIT IS ALWAYS ZERO
|
|
LD H,0 ; H := 0, DRIVER HAS NO MODES
|
|
LD L,FV_BASE ; L := BASE I/O ADDRESS
|
|
XOR A ; SIGNAL SUCCESS
|
|
RET
|
|
|
|
FV_VDASCS:
|
|
SYSCHKERR(ERR_NOTIMPL) ; NOT IMPLEMENTED (YET)
|
|
RET
|
|
|
|
FV_VDASCP:
|
|
CALL FV_XY ; SET CURSOR POSITION
|
|
XOR A ; SIGNAL SUCCESS
|
|
RET
|
|
|
|
FV_VDASAT:
|
|
; ATTRIBUTES NOT SUPPORTED BY HARDWARE
|
|
XOR A
|
|
RET
|
|
|
|
FV_VDASCO:
|
|
; CHARACTER COLOR NOT SUPPORT BY HARDWARE
|
|
XOR A ; SIGNAL SUCCESS
|
|
RET ; DONE
|
|
|
|
FV_VDAWRC:
|
|
LD A,E ; CHARACTER TO WRITE GOES IN A
|
|
CALL FV_PUTCHAR ; PUT IT ON THE SCREEN
|
|
XOR A ; SIGNAL SUCCESS
|
|
RET
|
|
|
|
FV_VDAFIL:
|
|
LD A,E ; FILL CHARACTER GOES IN A
|
|
EX DE,HL ; FILL LENGTH GOES IN DE
|
|
CALL FV_FILL ; DO THE FILL
|
|
XOR A ; SIGNAL SUCCESS
|
|
RET
|
|
|
|
FV_VDACPY:
|
|
; LENGTH IN HL, SOURCE ROW/COL IN DE, DEST IS FV_POS
|
|
; BLKCPY USES: HL=SOURCE, DE=DEST, BC=COUNT
|
|
PUSH HL ; SAVE LENGTH
|
|
CALL FV_XY2IDX ; ROW/COL IN DE -> SOURCE ADR IN HL
|
|
POP BC ; RECOVER LENGTH IN BC
|
|
LD DE,(FV_POS) ; PUT DEST IN DE
|
|
JP FV_BLKCPY ; DO A BLOCK COPY
|
|
|
|
FV_VDASCR:
|
|
LD A,E ; LOAD E INTO A
|
|
OR A ; SET FLAGS
|
|
RET Z ; IF ZERO, WE ARE DONE
|
|
PUSH DE ; SAVE E
|
|
JP M,FV_VDASCR1 ; E IS NEGATIVE, REVERSE SCROLL
|
|
CALL FV_SCROLL ; SCROLL FORWARD ONE LINE
|
|
POP DE ; RECOVER E
|
|
DEC E ; DECREMENT IT
|
|
JR FV_VDASCR ; LOOP
|
|
FV_VDASCR1:
|
|
CALL FV_RSCROLL ; SCROLL REVERSE ONE LINE
|
|
POP DE ; RECOVER E
|
|
INC E ; INCREMENT IT
|
|
JR FV_VDASCR ; LOOP
|
|
|
|
FV_STAT:
|
|
IN A,(FV_KBDST) ; GET STATUS
|
|
AND $01 ; ISOLATE DATA WAITING BIT
|
|
JP Z,CIO_IDLE ; NO DATA, EXIT VIA IDLE PROCESS
|
|
RET
|
|
|
|
FV_FLUSH:
|
|
XOR A ; SIGNAL SUCCESS
|
|
RET
|
|
|
|
FV_READ:
|
|
CALL FV_STAT ; GET STATUS
|
|
JR Z,FV_READ ; LOOP TILL DATA READY
|
|
IN A,(FV_KBDDATA) ; GET BYTE
|
|
LD E,A ; PUT IN E FOR RETURN
|
|
XOR A ; SIGNAL SUCCESS
|
|
RET ; DONE
|
|
|
|
;----------------------------------------------------------------------
|
|
; READ VALUE AT CURRENT VDU BUFFER POSITION
|
|
; RETURN E = CHARACTER, B = COLOUR, C = ATTRIBUTES
|
|
;----------------------------------------------------------------------
|
|
|
|
FV_VDARDC:
|
|
CALL FV_GETCHAR ; GET THE CHARACTER AT CUR CUR POS
|
|
LD E,A ; PUT IN E
|
|
LD BC,0 ; COLOR AND ATTR NOT SUPPORTED
|
|
XOR A ; SIGNAL SUCCESS
|
|
RET
|
|
;
|
|
;======================================================================
|
|
; FPGA VGA DRIVER - PRIVATE DRIVER FUNCTIONS
|
|
;======================================================================
|
|
;
|
|
;
|
|
;----------------------------------------------------------------------
|
|
; PROBE FOR FPGA VGA HARDWARE
|
|
;----------------------------------------------------------------------
|
|
;
|
|
; ON RETURN, ZF SET INDICATES HARDWARE FOUND
|
|
;
|
|
FV_PROBE:
|
|
XOR A ; ASSUME H/W EXISTS
|
|
RET
|
|
;
|
|
;----------------------------------------------------------------------
|
|
; CRTC DISPLAY CONTROLLER CHIP INITIALIZATION
|
|
;----------------------------------------------------------------------
|
|
;
|
|
FV_CRTINIT:
|
|
LD A,%11001111 ; WHITE ON BLACK, CURSOR ON, ENABLE OUTPUT
|
|
OUT (FV_CTL),A ; WRITE TO CONTROL PORT
|
|
XOR A ; ZERO ACCUM
|
|
RET ; DONE
|
|
;
|
|
;----------------------------------------------------------------------
|
|
; SET CURSOR POSITION TO ROW IN D AND COLUMN IN E
|
|
;----------------------------------------------------------------------
|
|
;
|
|
FV_XY:
|
|
CALL FV_HIDECUR ; HIDE THE CURSOR
|
|
PUSH DE ; SAVE NEW POSITION FOR NOW
|
|
CALL FV_XY2IDX ; CONVERT ROW/COL TO BUF IDX
|
|
LD (FV_POS),HL ; SAVE THE RESULT (DISPLAY POSITION)
|
|
POP DE ; RECOVER INCOMING ROW/COL
|
|
LD A,D ; GET ROW
|
|
OUT (FV_CROW),A ; SET ROW REGISTER
|
|
LD A,E ; GET COL
|
|
INC A ; 1..79,0 (WHY???)
|
|
CP 80 ; COL 80?
|
|
JR NZ, FV_XY1 ; SKIP IF NOT
|
|
XOR A ; ELSE MAKE IT ZERO!
|
|
FV_XY1:
|
|
OUT (FV_CCOL),A ; SET COL REGISTER
|
|
JP FV_SHOWCUR ; SHOW THE CURSOR AND EXIT
|
|
;
|
|
;----------------------------------------------------------------------
|
|
; CONVERT XY COORDINATES IN DE INTO LINEAR INDEX IN HL
|
|
; D=ROW, E=COL
|
|
;----------------------------------------------------------------------
|
|
;
|
|
FV_XY2IDX:
|
|
LD A,E ; SAVE COLUMN NUMBER IN A
|
|
LD H,D ; SET H TO ROW NUMBER
|
|
LD E,FV_COLS ; SET E TO ROW LENGTH
|
|
CALL MULT8 ; MULTIPLY TO GET ROW OFFSET, H * E = HL, E=0, B=0
|
|
LD E,A ; GET COLUMN BACK
|
|
ADD HL,DE ; ADD IT IN
|
|
RET ; RETURN
|
|
;
|
|
;----------------------------------------------------------------------
|
|
; SHOW OR HIDE CURSOR
|
|
;----------------------------------------------------------------------
|
|
;
|
|
FV_SHOWCUR:
|
|
LD A,%11001111 ; CONTROL PORT VALUE
|
|
;;;LD A,%11111111 ; CONTROL PORT VALUE
|
|
OUT (FV_CTL),A ; SET REGISTER
|
|
XOR A ; SIGNAL SUCCESS
|
|
RET ; DONE
|
|
;
|
|
FV_HIDECUR:
|
|
LD A,%11001111 ; CONTROL PORT VALUE
|
|
;;;LD A,%11111111 ; CONTROL PORT VALUE
|
|
OUT (FV_CTL),A ; SET REGISTER
|
|
XOR A ; SIGNAL SUCCESS
|
|
RET ; DONE
|
|
;
|
|
;----------------------------------------------------------------------
|
|
; (DE)SELECT FRAME BUFFER
|
|
;----------------------------------------------------------------------
|
|
;
|
|
FV_BUFSEL:
|
|
PUSH AF
|
|
LD A,$01
|
|
OUT (FV_BUFCTL),A
|
|
POP AF
|
|
RET
|
|
;
|
|
FV_BUFDESEL:
|
|
PUSH AF
|
|
XOR A
|
|
OUT (FV_BUFCTL),A
|
|
POP AF
|
|
RET
|
|
;
|
|
;----------------------------------------------------------------------
|
|
; WRITE VALUE IN A TO CURRENT VDU BUFFER POSITION, ADVANCE CURSOR
|
|
;----------------------------------------------------------------------
|
|
;
|
|
FV_PUTCHAR:
|
|
; WRITE CHAR AT CURRENT CURSOR POSITION.
|
|
PUSH AF ; SAVE INCOMING CHAR
|
|
CALL FV_HIDECUR ; HIDE CURSOR
|
|
CALL FV_BUFSEL ; SELECT FRAME BUFFER
|
|
POP AF
|
|
LD HL,(FV_POS) ; GET CUR BUF POSITION
|
|
LD DE,FV_FBUF ; START OF FRAME BUF
|
|
ADD HL,DE ; ADD IT IN
|
|
LD (HL),A ; PUT THE CHAR
|
|
;
|
|
; SET NEW POSITION
|
|
LD HL,(FV_POS) ; GET POSITION
|
|
INC HL ; BUMP POSITION
|
|
LD (FV_POS),HL ; SAVE NEW POSITION
|
|
;
|
|
; PUT CUROR IN PLACE
|
|
LD DE,FV_COLS ; COLS PER LINE
|
|
CALL DIV16 ; BC=ROW, HL=COL
|
|
LD D,C
|
|
LD E,L
|
|
CALL FV_XY
|
|
CALL FV_BUFDESEL ; DESELECT FRAME BUFFER
|
|
JP FV_SHOWCUR ; SHOW IT AND RETURN
|
|
;
|
|
;----------------------------------------------------------------------
|
|
; GET CHAR VALUE TO A FROM CURRENT VDU BUFFER POSITION
|
|
;----------------------------------------------------------------------
|
|
;
|
|
FV_GETCHAR:
|
|
XOR A
|
|
RET
|
|
;
|
|
;----------------------------------------------------------------------
|
|
; FILL AREA IN BUFFER WITH SPECIFIED CHARACTER AND CURRENT COLOR/ATTRIBUTE
|
|
; STARTING AT THE CURRENT FRAME BUFFER POSITION
|
|
; A: FILL CHARACTER
|
|
; DE: NUMBER OF CHARACTERS TO FILL
|
|
;----------------------------------------------------------------------
|
|
;
|
|
FV_FILL:
|
|
PUSH AF ; SAVE INCOMING FILL CHAR
|
|
CALL FV_HIDECUR ; HIDE CURSOR
|
|
CALL FV_BUFSEL ; SELECT BUFFER
|
|
LD HL,(FV_POS) ; CUR POS TO HL
|
|
LD BC,FV_FBUF ; ADR OF FRAME
|
|
ADD HL,BC ; ADD IT IN
|
|
POP AF
|
|
LD C,A ; FILL CHAR TO C
|
|
FV_FILL1:
|
|
LD A,D ; CHECK FILL
|
|
OR E ; ... COUNTER
|
|
JR Z,FV_FILL2 ; DONE IF ZERO
|
|
LD (HL),C ; FILL ONE CHAR
|
|
INC HL ; BUMP BUF PTR
|
|
DEC DE ; DEC FILL COUNTER
|
|
JR FV_FILL1 ; LOOP
|
|
;
|
|
FV_FILL2:
|
|
CALL FV_BUFDESEL ; DESELECT BUFFER
|
|
JP FV_SHOWCUR ; EXIT VIA SHOW CURSOR
|
|
;
|
|
;----------------------------------------------------------------------
|
|
; SCROLL ENTIRE SCREEN FORWARD BY ONE LINE (CURSOR POSITION UNCHANGED)
|
|
;----------------------------------------------------------------------
|
|
;
|
|
FV_SCROLL:
|
|
CALL FV_BUFSEL ; SELECT FRAME BUFFER
|
|
;
|
|
; COPY "UP" ONE LINE
|
|
LD HL,FV_FBUF + FV_COLS ; FROM SECOND LINE
|
|
LD DE,FV_FBUF ; TO FIRST LINE
|
|
LD BC,+(FV_ROWS - 1) * FV_COLS ; ALL BUT ONE LINE
|
|
LDIR ; DO IT
|
|
;
|
|
; FILL LAST LINE OF SCREEN
|
|
LD HL,FV_FBUF + ((FV_ROWS - 1) * FV_COLS) ; LAST LINE
|
|
LD A,' ' ; FILL CHAR
|
|
LD (HL),A ; COPY 1 CHAR
|
|
LD DE,FV_FBUF + ((FV_ROWS - 1) * FV_COLS) + 1 ; SECOND POS IN LAST LINE
|
|
LD BC,FV_COLS - 1 ; COLS PER LINE - 1
|
|
LDIR ; FILL IT
|
|
;
|
|
CALL FV_BUFDESEL ; DESELECT FRAME BUFFER
|
|
RET ; DONE
|
|
;
|
|
;----------------------------------------------------------------------
|
|
; REVERSE SCROLL ENTIRE SCREEN BY ONE LINE (CURSOR POSITION UNCHANGED)
|
|
;----------------------------------------------------------------------
|
|
;
|
|
FV_RSCROLL:
|
|
CALL FV_BUFSEL ; SELECT FRAME BUFFER
|
|
;
|
|
; COPY "DOWN" ONE LINE
|
|
LD HL,FV_FBUF + (FV_COLS * (FV_ROWS - 1)) - 1 ; FROM END OF SECOND TO LAST LINE
|
|
LD DE,FV_FBUF + (FV_COLS * FV_ROWS) - 1 ; TO END OF LAST LINE
|
|
LD BC,+(FV_ROWS - 1) * FV_COLS ; ALL BUT ONE LINE
|
|
LDDR ; DO IT IN REVERSE
|
|
;
|
|
; FILL FIRST LINE OF SCREEN
|
|
LD HL,FV_FBUF ; FIRST LINE
|
|
LD A,' ' ; FILL CHAR
|
|
LD (HL),A ; COPY 1 CHAR
|
|
LD DE,FV_FBUF + 1 ; SECOND POS IN FIRST LINE
|
|
LD BC,FV_COLS - 1 ; COLS PER LINE - 1
|
|
LDIR ; FILL IT
|
|
;
|
|
CALL FV_BUFDESEL ; DESELECT FRAME BUFFER
|
|
RET ; DONE
|
|
;
|
|
;----------------------------------------------------------------------
|
|
; BLOCK COPY BC BYTES FROM HL TO DE
|
|
;----------------------------------------------------------------------
|
|
;
|
|
FV_BLKCPY:
|
|
|
|
CALL FV_BUFSEL ; SELECT FRAME BUFFER
|
|
PUSH BC ; SAVE LENGTH
|
|
LD BC,FV_FBUF ; FRAME BUFFER ADR
|
|
ADD HL,BC ; ADD TO SOURCE
|
|
EX DE,HL ; EXCHANGE
|
|
ADD HL,BC ; ADD TO DEST
|
|
EX DE,HL ; EXCHANGE
|
|
POP BC ; RECOVER LENGTH
|
|
LDIR ; LDIR DOES THE COPY
|
|
CALL FV_BUFDESEL ; DESELECT FRAME BUFFER
|
|
RET ; DONE
|
|
;
|
|
;==================================================================================================
|
|
; FPGA VGA DRIVER - DATA
|
|
;==================================================================================================
|
|
;
|
|
FV_POS .DW 0 ; CURRENT DISPLAY POSITION
|
|
FV_ACTIVE .DB FALSE ; FLAG FOR DRIVER ACTIVE
|
|
;
|
|
;==================================================================================================
|
|
; VGA DRIVER - INSTANCE DATA
|
|
;==================================================================================================
|
|
;
|
|
FV_IDAT:
|
|
.DB KBDMODE_FV ; FPGA VGA KEYBOARD CONTROLLER
|
|
.DB FV_KBDST
|
|
.DB FV_KBDDATA
|
|
|