Sitenotice: 11/29/2018: The wiki is back. It turns out, some anti-virus product on my web server had an issue with the latest version of PHP. My server techs have resolved this issue, and things should be working again. During the investigation, I did restore to a backup from September. There is a chance that any changes done since then were lost, but I do not recall any edits. --OS-9 Al

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From CoCopedia - The Tandy/Radio Shack Color Computer Wiki
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Looking for CoCo help? If you are trying to do something with your old Color Computer, read this quick reference. Want to contribute to this wiki? Be sure to read this first. This CoCo wiki project was started on October 29, 2004. --OS-9 Al

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This page was last updated on 11/12/2015. Total Pages: 650. Total Files: 937.

Home / Hardware - Multi-Pak

Multi-pak 26-3024 Grey
Multi-pak 26-3024 Grey
Multi-pak 26-3024
Multi-pak 26-3024 White
Multi-pak 26-3124
Multi-pak 26-3124 White

The MULTI-PAK is a peripheral that plugs into the expansion slot (cartridge port) of the Color Computer and expands it to handle up to 4 cartridges interchangeable and can be used one at a time without having to put out one another. This exchange of the 4 slot can be done without shutting down the computer, although sometimes a reset is required. You can even do some things with several at once.

The following models exist:

  • 26-3024 Grey
  • 26-3024 White
  • 26-3124 White
  • 26-3124A White

There are also custom made MULTIPAK and 8 Slot MULTIPAK

To use the MULTI-PAK smoothly with Color Computer 3, use this:

Upgrading 26-3024 MPIs uses a PAL/GAL chip programmed for the CoCo 3's addressing pattern.

Upgrading the 26-3124 involves trace cutting and wiring in a 74LS10 chip to change the addresses.

To make a 20-3024 Multi-Pak Interface work with both a CoCo 1/2 and a CoCo 3 requires a piggybacked PAL/GAL with a switch to activate one or the other. I'm sure someone can figure out some circuitry to switch the 20-3124 type Multi-Pak Interface.

Neither setup is stable with the other CoCos. That is, once you upgrade to the CoCo 3 address set, your CoCo 1/2 will be unreliable with that Multi-Pak Interface.

26-3124 Multi-Pak Interface CoCo 3 Upgrade #1
26-3124 Multi-Pak Interface CoCo 3 Upgrade #2
26-3024 Multi-Pak Interface CoCo 3 upgrade By Robin W. Drake

Besides the two that provides Cloud-9 hardware Upgrade PAL Multi-Pak, but you have to send the MULTI-PAK.

The disk controller must be used in slot 4, and while you can use two disk controllers in the Multi-Pak Interface, problems exist.




The 74LS10 can be mounted on another (??), and attach the pin 7 & 14, with pin 7 & 14 of the mounted chip

MPI Mod for coco3



MPI Mod for coco3 diagram Mod3124.jpg