I borrowed a Cricut cartridge for a quick tear-down. Here's the "front" (the side that faces away from the cutter) of a "Cricut Sampler" cartridge:
And here's the back:
The markings don't show up in the picture, but the big chip on the PCB is an and it's paired with a . The 6 pin .1" header seems to be wired for in circuit serial programming. Here's a pin out:
| Header Pin | ATmega16 Pin |
|---|---|
| 1 | 2 - MISO |
| 2 | 5 - VCC |
| 3 | 3 - SCK |
| 4 | 1 - MOSI |
| 5 | 4 - RST |
| 6 | 6 - GND |
From the markings on the PCB, I would imagine that most cartridge hardware is identical.



