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Some fixes (mostly typos) in loader.s

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John Lorentzson 2025-07-15 16:45:21 +02:00
parent 5c41b48664
commit f81c0f7e65
1 changed files with 14 additions and 14 deletions
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28
wip-duuqnd/loader.s
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@ -1,11 +1,11 @@
;;; -*- Mode: asm; indent-tabs-mode: t; tab-width: 8 -*- ;;; -*- Mode: asm; indent-tabs-mode: t; tab-width: 8 -*-
;;This program reads a data stream from the joystick port and saves it in memory. ;; This program reads a data stream from the joystick port and saves it in memory.
;;The datastream format is as sutch: ;; The datastream format is as sutch:
;; ;;
;;############################################ ;; ############################################
;; 16-bit byte-length (big endian) | data ;; 16-bit byte-length (big endian) | data
;;############################################ ;; ############################################
;; The data comes from CTRL2 bit 0 and the clock is at bit 1 ;; The data comes from CTRL2 bit 0 and the clock is at bit 1
@ -21,19 +21,20 @@
;; More documentation on the Joystick port can be found here: https://www.c64-wiki.com/wiki/Joystick ;; More documentation on the Joystick port can be found here: https://www.c64-wiki.com/wiki/Joystick
CLKMASK = %00000010 progdest = $fe
CTRL2 = $DC00 CLKMASK = %00000010
CTRL2 = $DC00
.org $80d .org $80d
coldstart: ;; Draw a dollar sign on screen to show that program has loaded coldstart: ;; Draw an at sign on screen to show that program has loaded
lda #$0 lda #$0
sta $400 sta $400
waitstart: ;; Wait until joystick 1 has been pulled forwards to start this program waitstart: ;; Wait until joystick 1 has been pulled forwards to start the program
lda $dc01 lda $dc01
and #$01 and #$01
bne waitstart bne waitstart
;; Change boarder colour for debuging ;; Change border colour for debugging
lda #$00 lda #$00
sta $d020 sta $d020
teststart: teststart:
@ -55,7 +56,7 @@ check_for_load_start:
rts rts
start: start:
sei sei
;; change boarder collor for debuging purposes ;; change border color for debugging purposes
ldx #$02 ldx #$02
stx $d020 stx $d020
ldy #$00 ldy #$00
@ -109,8 +110,8 @@ wait_for_bit_start:
jmp done jmp done
@notdone: @notdone:
new_byte: new_byte:
;; BYTE is the byte beaing read from the stream. The bits are shifted from the left ;; BYTE is the byte being read from the stream. The bits are shifted from the left
;; When we shift out this 1 in BYTE bellow we save the BYTE to memory. ;; When we shift out this 1 in BYTE below we save the BYTE to memory.
lda #%10000000 lda #%10000000
sta BYTE sta BYTE
wait_for_bit_end: wait_for_bit_end:
@ -134,6 +135,5 @@ error:
BYTE = $400 BYTE = $400
LEN = $402 LEN = $402
progdest = $fe
stop: .word $0000 stop: .word $0000
loaded: .byte 0 loaded: .byte 0