diff --git a/doc/cx16.sgml b/doc/cx16.sgml index 78a51206b..a718e52fa 100644 --- a/doc/cx16.sgml +++ b/doc/cx16.sgml @@ -243,6 +243,12 @@ point to

+ + + This driver features a resolution of 640 across and 480 down with 2 colors, + black and white. +

+ Extended memory drivers

diff --git a/libsrc/cx16/tgi/cx640p1.s b/libsrc/cx16/tgi/cx640p1.s new file mode 100644 index 000000000..287160f6b --- /dev/null +++ b/libsrc/cx16/tgi/cx640p1.s @@ -0,0 +1,675 @@ +; +; Graphics driver for the 640 pixels across, 480 pixels down, 2 color mode +; on the Commander X16 +; +; 2024-06-11, Scott Hutter +; Based on code by Greg King +; + + .include "zeropage.inc" + + .include "tgi-kernel.inc" + .include "tgi-error.inc" + + .include "cbm_kernal.inc" + .include "cx16.inc" + + .macpack generic + .macpack module + + +; ------------------------------------------------------------------------ +; Header. Includes jump table and constants. + + module_header _cx640p1_tgi ; 640 pixels across, 1 pixel per bit + +; First part of the header is a structure that has a signature, +; and defines the capabilities of the driver. + + .byte $74, $67, $69 ; ASCII "tgi" + .byte TGI_API_VERSION ; TGI API version number + .addr $0000 ; Library reference + .word 640 ; X resolution + .word 480 ; Y resolution + .byte 2 ; Number of drawing colors + .byte 0 ; Number of screens available + .byte 8 ; System font X size + .byte 8 ; System font Y size + .word $0100 ; Aspect ratio (based on VGA display) + .byte 0 ; TGI driver flags + +; Next, comes the jump table. Currently, all entries must be valid, +; and may point to an RTS for test versions (function not implemented). + + .addr INSTALL + .addr UNINSTALL + .addr INIT + .addr DONE + .addr GETERROR + .addr CONTROL + .addr CLEAR + .addr SETVIEWPAGE + .addr SETDRAWPAGE + .addr SETCOLOR + .addr SETPALETTE + .addr GETPALETTE + .addr GETDEFPALETTE + .addr SETPIXEL + .addr GETPIXEL + .addr LINE + .addr BAR + .addr TEXTSTYLE + .addr OUTTEXT + + +; ------------------------------------------------------------------------ +; Constant + + + +; ------------------------------------------------------------------------ +; Data. + +; Variables mapped to the zero page segment variables. Some of these are +; used for passing parameters to the driver. + +X1 = ptr1 +Y1 = ptr2 +X2 = ptr3 +Y2 = ptr4 + +ADDR = tmp1 ; ADDR+1,2,3 + +TEMP = tmp3 +TEMP2 = tmp4 ; HORLINE +TEMP3 = sreg ; HORLINE + + +; Absolute variables used in the code + +.bss + +; The colors are indicies into a TGI palette. The TGI palette is indicies into +; VERA's palette. Vera's palette is a table of Red, Green, and Blue levels. +; The first 16 RGB elements mimic the Commodore 64's colors. + +SCRBASE: .res 1 ; High byte of screen base +BITMASK: .res 1 ; $00 = clear, $FF = set pixels + +defpalette: .res 2 +palette: .res 2 + +color: .res 1 ; Stroke and fill index +text_mode: .res 1 ; Old text mode + +tempX: .res 2 +tempY: .res 2 +ERR2: .res 1 +ERR: .res 1 +SY: .res 1 +SX: .res 1 +DY: .res 1 +DX: .res 1 +CURRENT_Y: .res 2 +CURRENT_X: .res 2 + +.data + +ERROR: .byte TGI_ERR_OK ; Error code + + +; Constants and tables + +.rodata + +veracolors: +col_black: .byte %00000000, %00000000 +col_white: .byte %11111111, %00001111 +col_red: .byte %00000000, %00001000 +col_cyan: .byte %11111110, %00001010 +col_purple: .byte %01001100, %00001100 +col_green: .byte %11000101, %00000000 +col_blue: .byte %00001010, %00000000 +col_yellow: .byte %11100111, %00001110 +col_orange: .byte %10000101, %00001101 +col_brown: .byte %01000000, %00000110 +col_lred: .byte %01110111, %00001111 +col_gray1: .byte %00110011, %00000011 +col_gray2: .byte %01110111, %00000111 +col_lgreen: .byte %11110110, %00001010 +col_lblue: .byte %10001111, %00000000 +col_gray3: .byte %10111011, %00001011 + +; Bit masks for setting pixels +bitMasks1: + .byte %10000000, %01000000, %00100000, %00010000 + .byte %00001000, %00000100, %00000010, %00000001 +bitMasks2: + .byte %01111111, %10111111, %11011111, %11101111 + .byte %11110111, %11111011, %11111101, %11111110 + + +.code + +; ------------------------------------------------------------------------ +; INSTALL routine. Is called after the driver is loaded into memory. May +; initialize anything that has to be done just once. Is probably empty +; most of the time. +; +; Must set an error code: NO + +INSTALL: +; Create the default palette. + lda #$00 + sta defpalette + lda #$01 + sta defpalette+1 + + ; Fall through. + +; ------------------------------------------------------------------------ +; UNINSTALL routine. Is called before the driver is removed from memory. May +; clean up anything done by INSTALL, but is probably empty most of the time. +; +; Must set an error code: NO + +UNINSTALL: + rts + +; ------------------------------------------------------------------------ +; INIT: Changes an already installed device from text mode to graphics +; mode. +; Note that INIT/DONE may be called multiple times while the driver +; is loaded, while INSTALL is called only once; so, any code that is needed +; to initiate variables and so on must go here. Setting the palette is not +; needed because that is called by the graphics kernel later. +; The graphics kernel never will call INIT when a graphics mode already is +; active, so there is no need to protect against that. +; +; Must set an error code: YES + +INIT: stz ERROR ; #TGI_ERR_OK + +; Save the current text mode. + + sec + jsr SCREEN_MODE + sta text_mode + +; Switch into (640 x 480 x 2 bpp) graphics mode. + + lda #%00000000 ; DCSEL = 0, VRAM port 1 + sta VERA::CTRL + lda #%00100001 ; Disable sprites, layer 1 enable, VGA + sta VERA::DISP::VIDEO + lda #%00000100 ; Bitmap mode enable + sta VERA::L1::CONFIG + lda #%00000001 ; Tile width 640 + sta VERA::L1::TILE_BASE + rts + +; ------------------------------------------------------------------------ +; DONE: Will be called to switch the graphics device back into text mode. +; The graphics kernel never will call DONE when no graphics mode is active, +; so there is no need to protect against that. +; +; Must set an error code: NO + +DONE: + jsr CINT + lda text_mode + clc + jmp SCREEN_MODE + +; ------------------------------------------------------------------------ +; GETERROR: Return the error code in .A, and clear it. + +GETERROR: + lda ERROR + stz ERROR + rts + +; ------------------------------------------------------------------------ +; CONTROL: Platform-/driver-specific entry point. +; +; Must set an error code: YES + +CONTROL: + lda #TGI_ERR_INV_FUNC + sta ERROR + rts + +; ------------------------------------------------------------------------ +; CLEAR: Clear the screen. +; +; Must set an error code: NO + +CLEAR: + .scope inner + + ; set up DCSEL=2 + lda #(2 << 1) + sta VERA::CTRL + + ; set cache writes + lda #$40 + tsb VERA::DISP::VIDEO ; VERA_FX_CTRL when DCSEL=2 + + ; set FX cache to all zeroes + lda #(6 << 1) + sta VERA::CTRL + + lda #$00 + sta VERA::DISP::VIDEO + sta VERA::DISP::HSCALE + sta VERA::DISP::VSCALE + sta VERA::DISP::FRAME + + stz VERA::CTRL + ; set address and increment for bitmap area + stz VERA::ADDR + stz VERA::ADDR + 1 + lda #$30 ; increment +4 + sta VERA::ADDR + 2 + + ldy #$F0 +@blank_outer: + ldx #$0A +@blank_loop: + + .repeat 8 + stz VERA::DATA0 + .endrep + + dex + bne @blank_loop + dey + bne @blank_outer + + ; set up DCSEL=2 + lda #(2 << 1) + sta VERA::CTRL + + ; set FX off (cache write bit 1 -> 0) + stz VERA::DISP::VIDEO ; VERA_FX_CTRL when DCSEL=2 + stz VERA::CTRL + + .endscope + rts + + +; ------------------------------------------------------------------------ +; SETVIEWPAGE: Set the visible page. Called with the new page in .A (0..n-1). +; The page number already is checked to be valid by the graphics kernel. +; +; Must set an error code: NO (will be called only if page OK) + +SETVIEWPAGE: + + ; Fall through. + +; ------------------------------------------------------------------------ +; SETDRAWPAGE: Set the drawable page. Called with the new page in .A (0..n-1). +; The page number already is checked to be valid by the graphics kernel. +; +; Must set an error code: NO (will be called only if page OK) + +SETDRAWPAGE: + rts + +; ------------------------------------------------------------------------ +; SETPALETTE: Set the palette (not available with all drivers/hardware). +; A pointer to the palette is passed in ptr1. Must set an error if palettes +; are not supported +; +; Must set an error code: YES + +SETPALETTE: + stz ERROR ; #TGI_ERR_OK + ldy #$01 ; Palette size of 2 colors +@L1: lda (ptr1),y ; Copy the palette + sta palette,y + dey + bpl @L1 + + ; set background color from palette color 0 + lda #$00 + sta VERA::ADDR + lda #$FA + sta VERA::ADDR+1 + lda #$01 + sta VERA::ADDR+2 ; write color RAM @ $1FA00 + + lda palette + asl + tay + lda veracolors,y + sta VERA::DATA0 + + inc VERA::ADDR ; $1FA01 + + lda palette + asl + tay + iny ; second byte of color + lda veracolors,y + sta VERA::DATA0 + + ; set foreground color from palette color 1 + inc VERA::ADDR ; $1FA02 + + lda palette+1 + asl + tay + lda veracolors,y + sta VERA::DATA0 + + inc VERA::ADDR ; $1FA03 + + lda palette+1 + asl + tay + iny ; second byte of color + lda veracolors,y + sta VERA::DATA0 + rts + +; ------------------------------------------------------------------------ +; SETCOLOR: Set the drawing color (in .A). The new color already is checked +; to be in a valid range (0..maxcolor). +; +; Must set an error code: NO (will be called only if color OK) + +SETCOLOR: + tax + beq @L1 + lda #$FF +@L1: sta BITMASK + stx color + rts + +; ------------------------------------------------------------------------ +; GETPALETTE: Return the current palette in .XA. Even drivers that cannot +; set the palette should return the default palette here, so there's no +; way for this function to fail. +; +; Must set an error code: NO + +GETPALETTE: + lda #palette + rts + +; ------------------------------------------------------------------------ +; GETDEFPALETTE: Return the default palette for the driver in .XA. All +; drivers should return something reasonable here, even drivers that don't +; support palettes, otherwise the caller has no way to determine the colors +; of the (not changable) palette. +; +; Must set an error code: NO (all drivers must have a default palette) + +GETDEFPALETTE: + lda #defpalette + rts + +; ------------------------------------------------------------------------ +; SETPIXEL: Draw one pixel at X1/Y1 = ptr1/ptr2 with the current drawing +; color. The co-ordinates passed to this function never are outside the +; visible screen area, so there is no need for clipping inside this function. +; +; Must set an error code: NO + +SETPIXEL: + jsr CALC + + stx TEMP + + lda ADDR + ldy ADDR+1 + ldx #$00 + + sta VERA::ADDR + sty VERA::ADDR + 1 + stx VERA::ADDR + 2 + + ldx TEMP + + lda BITMASK + beq @ahead + + ; if BITMASK = $00, white is line color + ; Set the bit in the byte at VERA_DATA0 + lda VERA::DATA0 ; Load the byte at memory address + ora bitMasks1,X ; OR with the bit mask + sta VERA::DATA0 ; Store back the modified byte + rts + +@ahead: + ; if BITMASK = $FF, black is line color + lda VERA::DATA0 ; Load the byte at memory address + and bitMasks2,X ; OR with the bit mask + sta VERA::DATA0 ; Store back the modified byte + rts + +; ------------------------------------------------------------------------ +; GETPIXEL: Read the color value of a pixel, and return it in .XA. The +; co-ordinates passed to this function never are outside the visible screen +; area, so there is no need for clipping inside this function. + +GETPIXEL: + jsr CALC + + stx TEMP + + lda ADDR + ldy ADDR+1 + ldx #$00 + + sta VERA::ADDR + sty VERA::ADDR + 1 + stx VERA::ADDR + 2 + + ldx TEMP + lda VERA::DATA0 ; Load the byte at memory address + and bitMasks1,X + + bne @ahead + + ldx #$00 + lda #$00 + rts + +@ahead: + ldx #$00 + lda #$01 + rts + +; ------------------------------------------------------------------------ +; BAR: Draw a filled rectangle with the corners X1/Y1, X2/Y2, where +; X1/Y1 = ptr1/ptr2 and X2/Y2 = ptr3/ptr4, using the current drawing color. +; Contrary to most other functions, the graphics kernel will sort and clip +; the co-ordinates before calling the driver; so on entry, the following +; conditions are valid: +; X1 <= X2 +; Y1 <= Y2 +; (X1 >= 0) && (X1 < XRES) +; (X2 >= 0) && (X2 < XRES) +; (Y1 >= 0) && (Y1 < YRES) +; (Y2 >= 0) && (Y2 < YRES) +; +; Must set an error code: NO + +BAR: + ; Initialize tempY with Y1 + lda Y1 + sta tempY + lda Y1+1 + sta tempY+1 + +@outer_loop: + ; Compare tempY with Y2 + lda tempY+1 + cmp Y2+1 + bcc @outer_continue ; If tempY high byte < Y2 high byte, continue + bne @outer_end ; If tempY high byte > Y2 high byte, end + lda tempY + cmp Y2 + bcc @outer_continue ; If tempY low byte < Y2 low byte, continue + beq @outer_end ; If tempY low byte = Y2 low byte, end + +@outer_continue: + ; Initialize tempX with X1 + lda X1 + sta tempX + lda X1+1 + sta tempX+1 + +@inner_loop: + ; Compare tempX with X2 + lda tempX+1 + cmp X2+1 + bcc @inner_continue ; If tempX high byte < X2 high byte, continue + bne @inner_end ; If tempX high byte > X2 high byte, end + lda tempX + cmp X2 + bcc @inner_continue ; If tempX low byte < X2 low byte, continue + +@inner_end: + ; Increment tempY + inc tempY + bne @outer_loop ; If no overflow, continue outer loop + inc tempY+1 ; If overflow, increment high byte + +@inner_continue: + ; Call setpixel(tempX, tempY) + lda X1 + pha + lda X1+1 + pha + lda Y1 + pha + lda Y1+1 + pha + + lda tempX + ldx tempX+1 + sta X1 + stx X1+1 + + lda tempY + ldx tempY+1 + sta Y1 + stx Y1+1 + + jsr SETPIXEL + + pla + sta Y1+1 + pla + sta Y1 + pla + sta X1+1 + pla + sta X1 + + ; Increment tempX + inc tempX + bne @inner_loop_check ; If no overflow, continue + inc tempX+1 ; If overflow, increment high byte + +@inner_loop_check: + ; Compare tempX with X2 again after increment + lda tempX+1 + cmp X2+1 + bcc @inner_continue ; If tempX high byte < X2 high byte, continue + bne @outer_increment ; If tempX high byte > X2 high byte, increment tempY + lda tempX + cmp X2 + bcc @inner_continue ; If tempX low byte < X2 low byte, continue + +@outer_increment: + ; Increment tempY + inc tempY + bne @outer_loop ; If no overflow, continue outer loop + inc tempY+1 ; If overflow, increment high byte + +@outer_end: + jmp @done + +@done: + rts + +; ------------------------------------------------------------------------ +; TEXTSTYLE: Set the style used when calling OUTTEXT. Text scaling in X and Y +; directions are passed in .X and .Y, the text direction is passed in .A. +; +; Must set an error code: NO + +TEXTSTYLE: + rts + +; ------------------------------------------------------------------------ +; OUTTEXT: Output text at X/Y = ptr1/ptr2 using the current color and the +; current text style. The text to output is given as a zero-terminated +; string with address in ptr3. +; +; Must set an error code: NO + +OUTTEXT: + rts + + +; ------------------------------------------------------------------------ +; Calculate all variables to plot the pixel at X1/Y1. +;------------------------ +;< X1,Y1 - pixel +;> ADDR - address of card +;> X - bit number (X1 & 7) +CALC: + lda Y1+1 + sta ADDR+1 + lda Y1 + asl + rol ADDR+1 + asl + rol ADDR+1 ; Y*4 + clc + adc Y1 + sta ADDR + lda Y1+1 + adc ADDR+1 + sta ADDR+1 ; Y*4+Y=Y*5 + lda ADDR + asl + rol ADDR+1 + asl + rol ADDR+1 + asl + rol ADDR+1 + asl + rol ADDR+1 + sta ADDR ; Y*5*16=Y*80 + lda X1+1 + sta TEMP + lda X1 + lsr TEMP + ror + lsr TEMP + ror + lsr TEMP + ror + clc + adc ADDR + sta ADDR + lda ADDR+1 ; ADDR = Y*80+x/8 + adc TEMP + sta ADDR+1 + lda ADDR+1 + lda X1 + and #7 + tax + rts + + +.include "../../tgi/tgidrv_line.inc"