Display_classic

160x120 color display. Compatible with programs intended for titokone display. It has a memory mapped framebuffer. This means that every pixel has a memory address. The first pixel (top left) is located at address 0x2000 (or 8192 in decimal). The three least significant bytes are mapped to the color values: 0x00000RGB, so writing 0x00000F00 to the framebuffer would result in a red pixel. The framebuffer is both readable and writable, but note that the it only stores the RGB values. The 5 other bytes will be lost.

Interrupts

Cause an interrupt at every refresh (~60Hz). See PIC.

Examples

See the screen test program for an example on how to interact with the display:

screen  equ 0x2000
spstash equ 0x0100

color_r dc 0x0f00
color_g dc 0x00f0
color_b dc 0x000f
color_c dc 0x00ff
color_m dc 0x0f0f
color_y dc 0x0ff0
color_bl dc 0x0000
color_w dc 0x0fff

load r5, =screen
sub  r5, =1     ; because push increments before writing!
load r3, r5

load r4, =160   ; R4 determines how many pixels to write in fill
mul  r4, =15

add  r3, r4     ; R3 has the address where we stop
load r1, color_r
call sp, fill
add  r5, r4

add  r3, r4
load r1, color_g
call sp, fill
add  r5, r4

add  r3, r4
load r1, color_b
call sp, fill
add  r5, r4

add  r3, r4
load r1, color_c
call sp, fill
add  r5, r4

add  r3, r4
load r1, color_m
call sp, fill
add  r5, r4

add  r3, r4
load r1, color_y
call sp, fill
add  r5, r4

add  r3, r4
load r1, color_bl
call sp, fill
add  r5, r4

add  r3, r4
load r1, color_w
call sp, fill


hcf ; Stop the program

fill    store sp, spstash
        load  sp, r5
        loop comp sp, r3
            jnles end
            push sp, r1
            jump loop
        load sp, spstash
        end exit sp, =0