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[go67/97 for Android] Creating .pck files in a text editor?
08-09-2015, 02:04 AM
Post: #10
RE: [go67/97 for Android] Creating .pck files in a text editor?
(08-08-2015 09:40 PM)Bill (Smithville NJ) Wrote:  
(08-08-2015 07:02 PM)lcwright1964 Wrote:  As I just suggested to you in our emails, I am learning that a program that not only translates the program steps to hex code but also generates the correct checksum is necessary. I tried to fiddle with Olivier's provided .pck files myself, or with my own generated files of very simple programs, and found quickly that if I edit the hex code directly, translating manually according to the key in the PPC journal, trying to use the revised card in the emulator throws an error--presumably because the old checksum doesn't match my changes.

As I admitted to you, I probably don't really understand the basics of a checksum in this context...


Hi Les,

The Checksum in this case is pretty simple. Sum up the first 33 records (Header plus 32 data records) and then MOD with 10000000H. That will give the Checksum Record. I have sent you an Excel spreadsheet showing the checksum calculation for the first few cards in the Standard Pack.

We now just need to get the Header Record decoded.

I am so glad my query inspired you to reactivate this old project. I wish that Olivier would chime in. I have emailed him through Google Play but get no reply, and other commenters there have mentioned that he hasn't been replying to bug reports (e.g., go71b crashes under the new Android OS, though it works gorgeously under previous ones).

I mentioned also in email to you there must be something coded in the pck files to specify whether a "card" is protected, and whether it is white with black font (user blanks) or brown with gold and white font (factory manufactured software). That is a lot of info to pack into that header line, esp. if we must also account for display setting, deg/rad/grad, and flags...

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RE: [go67/97 for Android] Creating .pck files in a text editor? - lcwright1964 - 08-09-2015 02:04 AM

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