'Software Toolworks protection--Black Hol'
Author:Lord Crass (guest: search)
Date: Sun, Mar 20th, 2011 @ 23:16 ( . )

This string of bytes appears to be written at a different density level, that's why it's coming in incorrectly. Here's the drive code that switches density and reads them:

.8:0493 LDA $1C00
.8:0496 PHA ; Push original $1C00 values (density specifically) to stack
.8:0497 AND #$9F
.8:0499 STA $1C00 ; switch to density %00, lowest density (same as track 31-35)
.8:049c LDY #$19 ; read up to $20 gap bytes before giving up
.8:049e BVC $049E ; wait for byte ready
.8:04a0 CLV
.8:04a1 LDA $1C01 ; read GCR byte
.8:04a4 CMP #$6A
.8:04a6 BEQ $04AB ; branch if found a $6A byte
.8:04a8 DEY
.8:04a9 BNE $049E ; loop until we find $6A or exceed number of tries
.8:04ab STA $0309 ; Store the byte in the $300 buffer
.8:04ae LDY #$03 ; Read 4 more bytes
.8:04b0 BVC $04B0 ; wait for byte
.8:04b2 CLV
.8:04b3 LDA $1C01 ; read GCR byte
.8:04b6 STA $0305,Y ; store at $308 down to $305
.8:04b9 DEY
.8:04ba BPL $04B0
.8:04bc PLA ; Pull original density level
.8:04bd STA $1C00 ; Set it


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Replies:
--* Software Toolworks protection--Black Hol
3/21/2011 @ 08:23--Pete Rittwage
3/21/2011 @ 20:24----J Achernar
3/21/2011 @ 21:26------Pete Rittwage
3/23/2011 @ 04:45--------hyper active
3/26/2011 @ 22:55----------J Achernar
3/27/2011 @ 13:45------------Pete Rittwage
1/18/2013 @ 18:13--------------hyper active

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