We are developing our own MCP from scratch: ciruits, control program, etc.

We are using Microchip's PIC16F628 microcontrollers for it. The 16F628 is basically a better, cheaper, and pin compatible version of the PIC 16F84.

Check out Byron A Jeff's page: The 16F628: Why the 16F84 is now obsolete He also has a simple programmer schematic and a patched version of the Linux picprg software to go with it. (I'm using his THVP programmer, which BTW can be seen in the pictures below)

Here's a preliminary block diagram of the circuit.

B: 04 Apr 2003: Added the following schematic of the MCP:

Notes about above circuit schematic: Things missing in the schematic

• the wires that are used to let the Master PIC (IC1) talk via a serial "bit-banging"-type protocol to the other PICs
• the LEDs for the keys (design not completed yet)
• as indicated, only 3 7-segment displays are shown, but there are 16 in total

Things that already work on my breadboard (see below for pictures)

• serial protocol (RS-232) of master PIC with PC
• 16 7-segment displays driven via time-multiplex technique with the 4067
• serial protocol (bit-banging type) from master PIC to display PIC
• set each display via a terminal program from the PC

Not built/tested yet

• keyboard matrix (connected to IC3)

Update 20030424: Tested

• PS/2 Mouse Interface
  • the idea is to use the quadrature encoders in the mouse as rotaries
  • why: mice are cheap, I payed less that 2 Euros (~2USD) for a el-cheapo PS/2 mouse
  • electronics already there
  • only two pins per mouse necessary (= 2 rotaries)
  • currently I have one PS/2 mouse connected to a PIC, working fine.
  • TODO: decoding mouse state inside PIC, and sending updates to display; adding a second mouse

Available Galleries:

MCP test circuit on breadboard gallery