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ProDOS BASIC.SYSTEM overwrites RNDL ($4E) - how to get random numbers

If you want to go straight into algorithms that use random numbers without having any keyboard input (e.g. boot apple, launches ProDOS, and this application is the first .SYSTEM or STARTUP that gets ...
bjb's user avatar
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1 vote

ProDOS BASIC.SYSTEM overwrites RNDL ($4E) - how to get random numbers

RNDL/H is incremented by the standard keyboard routine when waiting for a key as described in the Technical Reference (P.62 of the Apple II Reference Manual) And shown in the corresponding monitor ...
Raffzahn's user avatar
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4 votes
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ProDOS BASIC.SYSTEM overwrites RNDL ($4E) - how to get random numbers

It seems that RANDL ($4E) and RANDH ($4F) were re-purposed as a pointer named usrbuf that's used extensively throughout ProDOS. It's used as the destination for writing the bytes read from a file. ...
Nick Westgate's user avatar
2 votes

What is likely cause for sudden auto-rebooting of Apple II+ with Disk II?

Again, I pulled and reseated both adapter cards, from slot 0 (Language card) and slot 6 (Disk Controller); I pulled and reinserted all cables from all cards & connectors on mother board. I pulled ...
JTyler2's user avatar
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5 votes
Accepted

How Can Apple II DOS 3.3 Floppy Disks be Restored after Formatting with INIT?

The INIT command directs the drive to move the head to each of the first 35 tracks in turn, and overwrite the entire contents thereof. In performing this process, the drive uses two coils: an erase ...
supercat's user avatar
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