Re: Saving the text screen into strings???

> On May 1, 2026, at 6:20 AM, Patrick Ulland via Coco Allen! Always enjoy your exploits.

Always happy to see your name pop up!
> Sort of related, if you are porting from ZX81 BASIC the original program might include a mystery line like 10 LET A$=”” where A$ is never referenced anyplace else in the program.
> This is a workaround replacing(ish) CLEAR, READ, DATA, and WRITE to tape. The trick being ZX81 BASIC starts each line with a 2 byte number and a 2 byte length. To CLEAR space declare a line say 8K long, and copy the rest of the program above that.
> Why? If you don’t touch A$, the line containing A$ is never actually parsed, but it IS part of the BASIC listing. So build the dataset as you will and Viola! Saving the program to tape also saves the data.

I am really having a hard time visualizing this.

It reminds me of my VIC-20 days. Normally you would embed updated font data in DATA statements. But if your program was too big for the 5K memory, you could either make a pre-loader that POKEd in the new characters, or there was a way to save the memory — I guess like how we CSAVEM/SAVEM on the CoCo, but without the easy commands.

One of my programs loads and runs with the font. I must have learned a trick back then that let the END address of the BASIC extend into the RAM that the font data would go into, so when it loaded it loaded the BASIC program then that data, then maybe used some POKEs when it ran to set the real end or keep BASIC from overwriting things like CoCo’s CLEAR command (just without the easy command).

Fuzzy memories.


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