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Reduced columns to 46

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This commit is contained in:
Daniele Verducci su MatissePenguin 2021-02-12 18:48:42 +01:00
parent 9872968720
commit b395a4dd21
3 changed files with 31 additions and 212 deletions
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9
pat80-io-devices/composite-pal-adapter/software/avr-assembly/character_generator.asm
View File

@ -6,7 +6,7 @@
; This module generates the character pixels using the font present in rom
; and adds it on the framebuffer in the position indicated by POS_COARSE (Y).
.equ LINE_COLUMNS = 52 ; number of columns (characters or chunks) per line
.equ LINE_COLUMNS = 46 ; number of columns (characters or chunks) per line
; Draws character in register A to the screen at current coords (Y)
; @param r16 (HIGH_ACCUM) ascii code to display
@ -75,11 +75,8 @@ cursor_pos_home:
clr POS_ROWP
clr POS_FINE
; Load framebuffer start position to Y
; ldi YH, high(FRAMEBUFFER)
; ldi YL, low(FRAMEBUFFER)
; TODO: First 3 lines are not visible! Outside of screen!
ldi YH, high(0x780)
ldi YL, low(0x780)
ldi YH, high(FRAMEBUFFER)
ldi YL, low(FRAMEBUFFER)
ret
; Updates framebuffer pointer (Y) to point to current text cursor position (POS_COLUMN, POS_ROWP)

63
pat80-io-devices/composite-pal-adapter/software/avr-assembly/main.asm
View File

@ -1,7 +1,4 @@
; VIDEO COMPOSITE PAL IO DEVICE
; Implemented following timings in http://blog.retroleum.co.uk/electronics-articles/pal-tv-timing-and-voltages/
; Every line, for 52 times, it loads a byte from memory into PORTA register and then shifts the byte to the left to show another bit (do it 7 times)
; This also displays byte's MSB pixel "for free", as the video pin is PD7 (last bit of PORTA).
;
; INTERFACING WITH PAT80:
; Use PortB as data port. Before writing anything, issue a read (pin RW HIGH) and check the busy pin on the data port.
@ -55,7 +52,7 @@
; memory
.equ FRAMEBUFFER = 0x0100
.equ FRAMEBUFFER_END = 0x3EC0
.equ FRAMEBUFFER_END = 0x2AB0
; start vector
.org 0x0000
@ -92,53 +89,17 @@ main:
; test draw character routine
call cursor_pos_home
ldi r18, 0x21
draw_chars:
mov HIGH_ACCUM, r18
call draw_char
inc r18
cpi r18, 0x7E
brne draw_chars
ldi r18, 0x21
draw_chars2:
mov HIGH_ACCUM, r18
call draw_char
inc r18
cpi r18, 0x7E
brne draw_chars2
ldi r18, 0x21
draw_chars3:
mov HIGH_ACCUM, r18
call draw_char
inc r18
cpi r18, 0x7E
brne draw_chars3
ldi r18, 0x21
draw_chars4:
mov HIGH_ACCUM, r18
call draw_char
inc r18
cpi r18, 0x7E
brne draw_chars4
ldi r18, 0x21
draw_chars5:
mov HIGH_ACCUM, r18
call draw_char
inc r18
cpi r18, 0x7E
brne draw_chars5
ldi r18, 0x21
draw_chars6:
mov HIGH_ACCUM, r18
call draw_char
inc r18
cpi r18, 0x7E
brne draw_chars6
ldi r19, 12
dctest:
ldi r18, 0x21
draw_chars:
mov HIGH_ACCUM, r18
call draw_char
inc r18
cpi r18, 0x7E
brne draw_chars
dec r19
brne dctest

171
pat80-io-devices/composite-pal-adapter/software/avr-assembly/video_generator.asm
View File

@ -3,8 +3,12 @@
; * Video generator module *
; *******************************************
; Implemented following timings in http://blog.retroleum.co.uk/electronics-articles/pal-tv-timing-and-voltages/
; Every line, for 52 times, it loads a byte from memory into PORTA register and then shifts the byte to the left to show another bit (do it 7 times)
; This also displays byte's MSB pixel "for free", as the video pin is PD7 (last bit of PORTA).
; This module generates a Composite PAL monochrome signal with a resolution
; of 416x304 pixels of which only 376x232 pizels are visible (= 47x29 characters).
; of 416x304 pixels of which only 376x232 pizels are visible (= 46x29 characters).
; The signal is generated using 16-bit Timer1 and interrupts.
@ -25,6 +29,7 @@
.equ TIMER_DELAY_30US = 65535 - 690 ; 719 cycles @ 24Mhz (minus overhead)
.equ TIMER_DELAY_2US = 65535 - 17 ; 48 cycles @ 24Mhz (minus overhead)
.equ BACK_PORCH_DELAY = 258 ; 186 cycles back porch + 72 cycles to leave 3 chunks empty (image padding)
; ********* FUNCTIONS CALLED BY INTERRUPT ***********
@ -77,14 +82,13 @@ draw_picture:
; **** start line back porch: 8uS, 192 cycles @ 24Mhz
; leave time at the end for line setup and draw_line call
ldi VG_HIGH_ACCUM, 62 ; 1 cycle
ldi VG_HIGH_ACCUM, BACK_PORCH_DELAY/3 ; 1 cycle
l_sync_back_porch_loop:
dec VG_HIGH_ACCUM ; 1 cycle
brne l_sync_back_porch_loop ; 2 cycle if true, 1 if false
; **** end back porch
call draw_line ; 3 cycles (+ 3 to come back to on_line_drawn)
; **** draws line pixels: 52uS, 1248 cycles @ 24Mhz ****
@ -105,14 +109,13 @@ draw_picture:
; **** start line back porch: 8uS, 192 cycles @ 24Mhz
; leave time at the end for line setup and draw_line call
ldi VG_HIGH_ACCUM, 62 ; 1 cycle
ldi VG_HIGH_ACCUM, BACK_PORCH_DELAY/3 ; 1 cycle
l_sync_back_porch_loop2:
dec VG_HIGH_ACCUM ; 1 cycle
brne l_sync_back_porch_loop2 ; 2 cycle if true, 1 if false
; **** end back porch
call draw_line ; 3 cycles (+ 3 to come back to on_line_drawn)
; **** draws line pixels: 52uS, 1248 cycles @ 24Mhz ****
dec LINE_COUNTER ; decrement line countr ; 1 cycle
brne h_picture_loop ; if not 0, repeat h_picture_loop ; 2 cycle if true, 1 if false
@ -192,7 +195,7 @@ short_sync:
draw_line:
; NO loops, as this is time-strict
; 52 chunks of 8 pixels
; 46 chunks of 8 pixels
; chunk 1
ld A, X+ ; load pixel ; 2 cycles
@ -1344,154 +1347,12 @@ draw_line:
lsr A ; 1 cycle
out VIDEO_PORT_OUT, A ; 1 cycle
; chunk 47
ld A, X+ ; load pixel ; 2 cycles
out VIDEO_PORT_OUT, A ; 1 cycle
nop ; 1 cycle
lsr A ; 1 cycle
out VIDEO_PORT_OUT, A ; 1 cycle
nop ; 1 cycle
lsr A ; 1 cycle
out VIDEO_PORT_OUT, A ; 1 cycle
nop ; 1 cycle
lsr A ; 1 cycle
out VIDEO_PORT_OUT, A ; 1 cycle
nop ; 1 cycle
lsr A ; 1 cycle
out VIDEO_PORT_OUT, A ; 1 cycle
nop ; 1 cycle
lsr A ; 1 cycle
out VIDEO_PORT_OUT, A ; 1 cycle
nop ; 1 cycle
lsr A ; 1 cycle
out VIDEO_PORT_OUT, A ; 1 cycle
nop ; 1 cycle
lsr A ; 1 cycle
out VIDEO_PORT_OUT, A ; 1 cycle
; chunk 48
ld A, X+ ; load pixel ; 2 cycles
out VIDEO_PORT_OUT, A ; 1 cycle
nop ; 1 cycle
lsr A ; 1 cycle
out VIDEO_PORT_OUT, A ; 1 cycle
nop ; 1 cycle
lsr A ; 1 cycle
out VIDEO_PORT_OUT, A ; 1 cycle
nop ; 1 cycle
lsr A ; 1 cycle
out VIDEO_PORT_OUT, A ; 1 cycle
nop ; 1 cycle
lsr A ; 1 cycle
out VIDEO_PORT_OUT, A ; 1 cycle
nop ; 1 cycle
lsr A ; 1 cycle
out VIDEO_PORT_OUT, A ; 1 cycle
nop ; 1 cycle
lsr A ; 1 cycle
out VIDEO_PORT_OUT, A ; 1 cycle
nop ; 1 cycle
lsr A ; 1 cycle
out VIDEO_PORT_OUT, A ; 1 cycle
; chunk 49
ld A, X+ ; load pixel ; 2 cycles
out VIDEO_PORT_OUT, A ; 1 cycle
nop ; 1 cycle
lsr A ; 1 cycle
out VIDEO_PORT_OUT, A ; 1 cycle
nop ; 1 cycle
lsr A ; 1 cycle
out VIDEO_PORT_OUT, A ; 1 cycle
nop ; 1 cycle
lsr A ; 1 cycle
out VIDEO_PORT_OUT, A ; 1 cycle
nop ; 1 cycle
lsr A ; 1 cycle
out VIDEO_PORT_OUT, A ; 1 cycle
nop ; 1 cycle
lsr A ; 1 cycle
out VIDEO_PORT_OUT, A ; 1 cycle
nop ; 1 cycle
lsr A ; 1 cycle
out VIDEO_PORT_OUT, A ; 1 cycle
nop ; 1 cycle
lsr A ; 1 cycle
out VIDEO_PORT_OUT, A ; 1 cycle
; chunk 50
ld A, X+ ; load pixel ; 2 cycles
out VIDEO_PORT_OUT, A ; 1 cycle
nop ; 1 cycle
lsr A ; 1 cycle
out VIDEO_PORT_OUT, A ; 1 cycle
nop ; 1 cycle
lsr A ; 1 cycle
out VIDEO_PORT_OUT, A ; 1 cycle
nop ; 1 cycle
lsr A ; 1 cycle
out VIDEO_PORT_OUT, A ; 1 cycle
nop ; 1 cycle
lsr A ; 1 cycle
out VIDEO_PORT_OUT, A ; 1 cycle
nop ; 1 cycle
lsr A ; 1 cycle
out VIDEO_PORT_OUT, A ; 1 cycle
nop ; 1 cycle
lsr A ; 1 cycle
out VIDEO_PORT_OUT, A ; 1 cycle
nop ; 1 cycle
lsr A ; 1 cycle
out VIDEO_PORT_OUT, A ; 1 cycle
; chunk 51
ld A, X+ ; load pixel ; 2 cycles
out VIDEO_PORT_OUT, A ; 1 cycle
nop ; 1 cycle
lsr A ; 1 cycle
out VIDEO_PORT_OUT, A ; 1 cycle
nop ; 1 cycle
lsr A ; 1 cycle
out VIDEO_PORT_OUT, A ; 1 cycle
nop ; 1 cycle
lsr A ; 1 cycle
out VIDEO_PORT_OUT, A ; 1 cycle
nop ; 1 cycle
lsr A ; 1 cycle
out VIDEO_PORT_OUT, A ; 1 cycle
nop ; 1 cycle
lsr A ; 1 cycle
out VIDEO_PORT_OUT, A ; 1 cycle
nop ; 1 cycle
lsr A ; 1 cycle
out VIDEO_PORT_OUT, A ; 1 cycle
nop ; 1 cycle
lsr A ; 1 cycle
out VIDEO_PORT_OUT, A ; 1 cycle
; chunk 52
ld A, X+ ; load pixel ; 2 cycles
out VIDEO_PORT_OUT, A ; 1 cycle
nop ; 1 cycle
lsr A ; 1 cycle
out VIDEO_PORT_OUT, A ; 1 cycle
nop ; 1 cycle
lsr A ; 1 cycle
out VIDEO_PORT_OUT, A ; 1 cycle
nop ; 1 cycle
lsr A ; 1 cycle
out VIDEO_PORT_OUT, A ; 1 cycle
nop ; 1 cycle
lsr A ; 1 cycle
out VIDEO_PORT_OUT, A ; 1 cycle
nop ; 1 cycle
lsr A ; 1 cycle
out VIDEO_PORT_OUT, A ; 1 cycle
nop ; 1 cycle
lsr A ; 1 cycle
out VIDEO_PORT_OUT, A ; 1 cycle
nop ; 1 cycle
lsr A ; 1 cycle
out VIDEO_PORT_OUT, A ; 1 cycle
; chunk 47, 48, 49 (blank)
clr A ; 1 cycle
out VIDEO_PORT_OUT, A ; 1 cycle
ldi VG_HIGH_ACCUM, 23 ; 1 cycle
eol_porch_loop: ; requires 3 cpu cycles
dec VG_HIGH_ACCUM ; 1 cycle
brne eol_porch_loop ; 2 if jumps, 1 if continues
ret