| MediaWiki:Sitenotice |
|---|
| 2026-03-12: Cocopedia.com is now using a new caching system that should make things faster. Please let me know if you encounter any new issues.
2026-03-15: MediaWiki has been reinstalled and the old database and files restored. It was pretty clogged up from being upgraded so many times since 2004. I am also testing out Cloudflare to see if it can prevent the 'bot assaults that took the site down last year. 2026-03-16: Special thanks to Don Barber for hosting a backup mirror of CoCopedia: https://cocopedia.dgb3.net |
FD-502 (26-3133)
This is the last Tandy controller. It reverted back to mere solder-tinned edge connectors, for whatever reason (cost?!). Unlike every previous model, this one uses a 28-pin ROM rather than a 24-pin ROM for Disk BASIC. This model was introduced in the 1988 Radio Shack catalog. All Radio Shack (and some third-party) CoCo floppy controllers use a pair of 7416 open-collector buffer chips to communicate with the floppy drive(s). These chips can fail and cause various strange symptoms. They may be replaced with 7406 chips, which are more rugged (the 7416 is rated at 15V, while the 7406 is rated at 30V). Socketing the replacement chips makes future replacement much easier, should it become necessary.
