Apple-2-SW/prodos-drivers
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This commit is contained in:
Joshua Bell 2019-06-14 21:00:53 -07:00
parent a2bc49a38b
commit 4d4a164e30
1 changed files with 10 additions and 6 deletions
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16
ram.system.s
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@ -3,12 +3,14 @@
.setcpu "6502" .setcpu "6502"
.include "apple2.inc" .include "apple2.inc"
.include "apple2.mac"
.include "inc/macros.inc" .include "inc/macros.inc"
.include "inc/apple2.inc" .include "inc/apple2.inc"
.include "inc/prodos.inc" .include "inc/prodos.inc"
.include "opcodes.inc" .include "opcodes.inc"
zp_sig_addr := $06
zpproc_addr := $B0 zpproc_addr := $B0
zpproc_relay_addr := $2D0 zpproc_relay_addr := $2D0
@ -304,9 +306,9 @@ break:
beq fail beq fail
;; Check for ZP signature - if not found, set it and install. ;; Check for ZP signature - if not found, set it and install.
ldx #2 ldx #sig_len-1
: lda L23A0,x : lda sig,x
cmp $06,x cmp zp_sig_addr,x
bne set_sig bne set_sig
dex dex
bpl :- bpl :-
@ -317,9 +319,9 @@ break:
fail: jmp do_chain fail: jmp do_chain
sloop: lda L23A0,x sloop: lda sig,x
set_sig: set_sig:
sta $06,x sta zp_sig_addr,x
dex dex
bpl sloop bpl sloop
@ -570,7 +572,9 @@ num_banks_minus_one:
.byte 0 .byte 0
L239F: .byte 0 L239F: .byte 0
L23A0: .byte $C7, $C5, $C2 ; signature sequence ???
sig: scrcode "GEB" ; signature sequence - Glen E. Bredon
sig_len = * - sig
;; Volume Directory Header ;; Volume Directory Header
.proc vol_dir_header .proc vol_dir_header