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Change the Atari BASIC "READY" Prompt

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Change the Atari BASIC "READY" Prompt

"HELLO", there.

Paul Lefebvre
Oct 7, 2022
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Change the Atari BASIC "READY" Prompt

www.goto10retro.com

One fun thing you can do with an Atari XL/XE is move the ROM BASIC into RAM. And once it is in RAM you can modify it with the POKE command.

In Compute! November 1985 Reader Comments, there was a short program to copy BASIC to RAM, which also patches the Rev B BASIC to be Rev C.

There were three revisions of Atari BASIC, Rev A, B and C. Rev A was shipped on cartridge for the 400/800/1200XL computers and had a keyboard lockup bug that could occur when deleting code in specific situations.

Atari attempted to fix this bug in Rev B (and did), but in the process created other bugs. The worst being that 16 bytes are added to a program each time it is saved.

These bugs were fixed in Rev C, which was made available on cartridge and built-in to the 65XE, 130XE and XEGS.

Other than the bug fixes, there were no other functionality changes between revisions of Atari BASIC.

With this code in hand, I found out where the “READY” prompt was stored (location 48499 to 48503) and wrote a quick program to change it. Here is a scan of the printout from my old binder of Atari stuff:

Since this is just changing the bytes, the new name can be no longer than “READY” itself or 5 characters, otherwise it would overwrite some of the BASIC’s actual code and more than likely crash everything. It pads things out with spaces if fewer than 5 characters are typed.

Now my READY prompt can instead be “HELLO”:

Consider becoming a paid subscriber, which has a disk image with this program (and many, many others) as one of several perks.

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Change the Atari BASIC "READY" Prompt

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