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16
ram.system.s
16
ram.system.s
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@ -3,12 +3,14 @@
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.setcpu "6502"
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.include "apple2.inc"
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.include "apple2.mac"
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.include "inc/macros.inc"
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.include "inc/apple2.inc"
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.include "inc/prodos.inc"
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.include "opcodes.inc"
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zp_sig_addr := $06
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zpproc_addr := $B0
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zpproc_relay_addr := $2D0
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@ -304,9 +306,9 @@ break:
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beq fail
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;; Check for ZP signature - if not found, set it and install.
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ldx #2
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: lda L23A0,x
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cmp $06,x
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ldx #sig_len-1
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: lda sig,x
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cmp zp_sig_addr,x
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bne set_sig
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dex
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bpl :-
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@ -317,9 +319,9 @@ break:
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fail: jmp do_chain
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sloop: lda L23A0,x
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sloop: lda sig,x
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set_sig:
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sta $06,x
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sta zp_sig_addr,x
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dex
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bpl sloop
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@ -570,7 +572,9 @@ num_banks_minus_one:
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.byte 0
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L239F: .byte 0
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L23A0: .byte $C7, $C5, $C2 ; signature sequence ???
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sig: scrcode "GEB" ; signature sequence - Glen E. Bredon
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sig_len = * - sig
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;; Volume Directory Header
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.proc vol_dir_header
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