MediaWiki:Sitenotice:
2024-03-02: The wiki ran out of disk space, so things were not working. This has been resolved by adding another 5GB of quota ;-) Thanks to Tim Lindner for reporting the issues.
2020-05-17: If a page gives you an error about some revision not being found, just EDIT the page and the old page should appear in the editor. If it does, just SAVE that and the page should be restored. OS-9 Al (talk) 12:22, 17 May 2020 (CDT)
External Hardware IO Address Map
External Hardware IO Address Map
Tandy designated IO addresses from $FF60 to $FF7F for add-on hardware, but several parties chose to build in the $FF40-$FF5F and $FF80-FF8F ranges as well. Here are known IO addresses for add-on hardware.
- FF40-FF4B Floppy Disk Controllers. See Hardware#Floppy_Disk_Controllers for list.
- FF40-FF4B MEGA mini MPI Serial UART A (gated via $FF7F)
- FF40-FF45 MEGA mini MPI Extended MPI Features (gated via $FF7F)
- FF40-FF41 Game Master Cart
- FF41-FF42 Becker Port used by CoCo3FPGA and some emulators for DriveWire access
- FF4C-FF4F Some third party Floppy Disk Controlers: Sardis, JFD, Disto Super Disk Controller, and Disto Super Disk Controller II
- FF50-FF5F Glenside IDE Controller (first jumper option)
- FF50-FF54 MEGA mini MPI YMF-262 sound generator (gated via $FF7F)
- FF50-FF57 Disto Super Disk Controller
- FF50-FF59 Cloud-9 SuperIDE Interface Default Address Range, modified with jumpers
- FF50-FF5F Disto Super Disk Controller II
- FF50-FF5B MEGA mini MPI Serial UART B (gated via $FF7F)
- FF5A-FF5F CoCo PSG
- FF59 Cloud-9 miniFLASH default address, modified with jumpers
- FF60-FF62 X-Pad Model GT-116
- FF64-FF67 Retro Innovations CoCoFLASH
- FF68-FF6B Deluxe RS232 Pak
- FF68-FF6B CoCoIO (first jumper option)
- FF6C-FF6F Direct Connect Modem Pak
- FF6E-FF6F MIDI Maestro
- FF70-FF7F Glenside IDE Controller (second jumper option)
- FF70-FF73 Am9511 Arithmetic Processor Unit Pak (default address, modified with dip switches)
- FF74-FF75 Cloud-9 TC^3 SCSI Interface default settings, modified with jumpers
- FF74-FF77 Disto Super Disk Controller II
- FF7A-FF7B Orchestra-90 CC (26-3143)
- FF78-FF7B CocoIO (second jumper option)
- FF78-FF79 & FF7C Cloud-9 SuperIDE Interface Real Time Clock
- FF7D-FF7E Speech/Sound Cartridge (26-3144A)
- FF7F Multi-Pak Slot Selection Register
- FF80-FF84 Speech Systems Super Voice
- FFE0-FFE9 & FFEF GIME-X for CoCo 3
Note some devices overlap each other; these devices will conflict and cannot be used together without modification.
Built-in IO devices (such as the PIAs ($FF00-FF3F), CoCo3 GIME ($FF90-FFBF), and SAM ($FFC0-FFDF)) also take the IO space. The 6809/6309 CPU uses $FFF0-FFFF for interrupt vectors.