JCM Universal Keyboard Encoder

JCM Universal Keyboard Encoder


Universal Replacement for the General Instrument AY-5-3600-PRO, also known as the 9600-PRO and other names.

“Just received your keyboard encoder for the Apple //e.  Does the trick – obviously the original is dead. I was going to buy an original part but was a bit nervous about fake products so went for a modern replacement.” – Lenny, from New Zealand

See Below for a full list of supported systems and chips.

Jumper Meanings

  • No Jumpers = Apple //e, Apple //c, Apple //c Plus
  • Jumper on 1 = Apple ///
  • Jumper on 2 = Apple /// Plus
  • Jumper on both 1 and 2 = Apple ][+ (for units that use the AY style encoder)


  • Is your encoder actually faulty? Please note that not all keyboard issues are caused by a faulty encoder. Any number of other support chips in your vintage machine may cause similar symptoms.
  • Apple //c and Apple //c Plus Owners: select the Without Jumpers option. This is to ensure the encoder clears any obstructions above it, like expansion cards.
  • This is not compatible with Datanetics keyboards using the MM5740-style encoder. For those systems, use my MM5740AAE Replacement Encoder.


The encoder in my Apple /// failed and I didn’t want to scavenge another Apple /// to get one. So designed a replacement. After several revisions and help from some awesome collaborators, we come to the final version – a universal replacement for the AY-5-3600-PRO that works in basically everything.

Includes the factory keymapping as used in the Apple //e and Apple //c, plus many other vintage computers. It also includes the custom mapping used by the Apple /// and Apple /// Plus. One encoder supports them all. Need an off-the-shelf solution for your hobbyist electronics project? This will fit the bill!

Designed by Joe Strosnider, with testing by Petar Puskarich, all key functions have been meticulously mapped, traced and tested. This encoder successfully passes the Apple /// Dealer Diagnostics, Apple /// Plus Dealer Diagnostics and Apple //e Diagnostics 2.1.

Each unit lovingly assembled by hand in Ohio. ♥


Supported Systems and Chips

Chip Numbers

  • AY-5-3600-PRO
  • AY-5-3600-931
  • 9600-PRO
  • KR3600-070
  • 324-0035
  • 331-0931-B
  • 341-0035-A
  • 342-0035
  • NKBD-931


  • Apple ][+ with Separate Encoder Board
  • Apple //e, all models
  • Apple //c
  • Apple //c Plus
  • Apple ///
  • Apple /// Plus

Has been fully tested in: Apple ][, Apple ][+, Apple //e, Apple //c, Apple /// and Apple /// Plus.

Encoder can support many other custom key mappings. If you would like a custom design, contact us for details.

Additional information

Weight 0.3 oz
Dimensions 2.1 × 0.75 × 0.75 in
Header Type

With Jumpers, Without Jumpers

Include 40 Pin Socket?

No, Yes