From c90516ab5191463065e4ada2dd5fd6c0d5143025 Mon Sep 17 00:00:00 2001 From: Daniele Verducci su MatissePenguin Date: Fri, 12 Feb 2021 19:23:08 +0100 Subject: [PATCH] horyzontally centered image in CRT --- .../composite-pal-adapter/software/avr-assembly/main.asm | 2 +- .../software/avr-assembly/video_generator.asm | 4 ++-- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/pat80-io-devices/composite-pal-adapter/software/avr-assembly/main.asm b/pat80-io-devices/composite-pal-adapter/software/avr-assembly/main.asm index 076e924..acdde40 100644 --- a/pat80-io-devices/composite-pal-adapter/software/avr-assembly/main.asm +++ b/pat80-io-devices/composite-pal-adapter/software/avr-assembly/main.asm @@ -89,7 +89,7 @@ main: ; test draw character routine call cursor_pos_home - ldi r19, 12 + ldi r19, 14 dctest: ldi r18, 0x21 draw_chars: diff --git a/pat80-io-devices/composite-pal-adapter/software/avr-assembly/video_generator.asm b/pat80-io-devices/composite-pal-adapter/software/avr-assembly/video_generator.asm index 24e5c5d..ad95fba 100644 --- a/pat80-io-devices/composite-pal-adapter/software/avr-assembly/video_generator.asm +++ b/pat80-io-devices/composite-pal-adapter/software/avr-assembly/video_generator.asm @@ -29,7 +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) +.equ BACK_PORCH_DELAY = 234 ; 186 cycles back porch + 48 cycles to leave 2 chunks empty (image padding) ; ********* FUNCTIONS CALLED BY INTERRUPT *********** @@ -1350,7 +1350,7 @@ draw_line: ; chunk 47, 48, 49 (blank) clr A ; 1 cycle out VIDEO_PORT_OUT, A ; 1 cycle - ldi VG_HIGH_ACCUM, 23 ; 1 cycle + ldi VG_HIGH_ACCUM, 31 ; 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