Atari EMMU CO25953 replacement - DIY soldering kit

This is a replacement for the CO25953 EMMU used in Atari XE 8-bit computers. The Atari EMMU controls a 16KB bank switching window in the memory map of the Atari XE line, allowing for 128KB of memory to be installed in these computers. The Atari 130XE comes with the EMMU and 128KB of memory installed by default. The Atari 65XE and 800XE have 64KB by default and no EMMU. By installing additional memory and the EMMU, these computers can be upgraded to 128KB of memory.

Features:

• Does not require installation of U35, compatible with mainboards without position U35.
• Compact design that does not mechanically interfere with RF shield.

This part is compatible with the following computers:

• Atari 65XE
• Atari 130XE
• Atari 800XE  (not compatible with 800XL!)

This part can be used to replace a broken EMMU in an Atari 130XE or to upgrade an Atari 65XE or 800XE to 128KB of memory.

This part is my own design, it isn't based on existing designs found on the internet. The part consists of a GAL chip and adapter PCB. The DIP IC is soldered directly to the PCB with widened legs. This way, the mechanical construction avoids mechanical conflict with the RF shield, while avoiding the need for SMD components (but no space is left, see photo).

You will receive:

• Adapter PCB
• GAL chip pre-programmed with EMMU equations
• 2 * 8 pin male header
• Instruction manual

Atari part numbers use the typewriter character set where O and 0 are identical and so are I and 1. Therefore this part is sometimes referred to as C025953.

Would you like a to buy an already assembled EMMU? Please look here.