MediaWiki:Sitenotice:
2025-12-29: I have restored the wiki to a backup from the end of November. Starting in September 2025, accesses went form the 800MB-1.2GB range per month to 26GB in September, 42GB in October, and 70GB in November with most accesses originating from China. As soon as I realized what was causing all the access problems in November, I shut it down (it had reached 36GB by then) behind a password/login screen. The database had gotten corrupted, and I tried a restore from just before the spike in access but that didn't work. Thus, end of November. I still have the other daily backups so if there were any important additions in December, let me know and maybe they can be recovered. - Allen H.

PIA

From CoCopedia - The Tandy/Radio Shack Color Computer Wiki
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The Peripheral Interface Adapter is a chip, of which there are two in your CoCo, that is used for handling I/O, amongst other things.


Keyboard

The keyboard can be scanned through PIA-1 by pulling two values from addresses $FF00 and $FF02. Color Basic ROM, when running a prompt, converts these to ASCII values to be printed to the screen at cursor position. The first address ($FF00) represents the keyboard rows as well as the joystick button, and the second address ($FF02) the keyboard columns. These two value correspond to ASCII values according to the following table:

0 1 2 3 4 5 6 7
0
1
2
3
4
5
6
7

(under construction)