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Pyjamarama   [1984]

Pyjamarama Released by :
ABC Crackings

Release Date :
1984

Type :
C64 Crack

User rating:awaiting 8 votes (8 left)

Credits :
No credits found


Intro used in this crack:
DownloadABC Crackings Intro by ABC Crackings

Download :

Look for downloads on external sites:
 Pokefinder.org


User Comment
Submitted by iAN CooG on 4 January 2022
I don't know if it's born bad or there are some bad bytes due to bad transfer, but what I noticed is:
1) byte at $a000 is $55, most probably due to a memory dump done after a reset, while the xor pattern tells me that should be a $ac.
9FF0:  9C 9D 9E 9F-A0 A1 A2 A3-A4 A5 A6 A7-A8 A9 AA AB
A000:  55 AD AE AF-B0 B1 B2 B0-B4 B5 B6 B7-B8 B9 BA B5

becomes
9FF0:  9C 9D 9E 9F-A0 A1 A2 A3-A4 A5 A6 A7-A8 A9 AA AB
A000:  AC AD AE AF-B0 B1 B2 B0-B4 B5 B6 B7-B8 B9 BA B5

2) it manipulates $01 to bankswitch too many times without stopping interrupts. It's a call for disasters.
AB1F  20 81 FF  JSR $FF81
AB22  78        SEI 
AB23  A9 EA     LDA #$EA
AB25  8D 15 03  STA $0315
AB28  A9 31     LDA #$31
AB2A  8D 14 03  STA $0314
AB2D  58        CLI <- patched with 78 (SEI)
AB2E  60        RTS 

3) same after decrypting, it leaves $01=#$35 but doesn't set the vector $fffe/fffe before calling another CLI, and there happens the disaster, IRQ is triggered too soon and crashes by jumping to $ffff.
.C:09f7  A5 01       LDA $01
.C:09f9  09 01       ORA #$01
.C:09fb  29 FD       AND #$FD
.C:09fd  85 01       STA $01   ; $01=#$35
.C:09ff  20 D4 09    JSR $09D4 ;<- decryption for the next bytes

.C:0a2c  58          CLI       ;<- nah, don't!
.C:0a2d  20 3C 42    JSR $423C

to patch it, and have a SEI ($78) there, the original byte at $0a2c which contains $80 must be patched with $a0 ($58^$80 gives the xor value used in that location $d8, then $78^$d8 is $a0)

The fixed d64 is added only to show that the program can be fixed to work.
User Comment
Submitted by Celtic on 4 September 2014
doesnt work for me past the intro.
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CSDb (Commodore 64 Scene Database) is a website which goal is to gather as much information and material about the scene around the commodore 64 computer - the worlds most popular home computer throughout time. Here you can find almost anything which was ever made for the commodore 64, and more is being added every day. As this website is scene related, you can mostly find demos, music and graphics made by the people who made the scene (the sceners), but you can also find a lot of the old classic games here. Try out the search box in the top right corner, or check out the CSDb main page for the latest additions.
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