RicohAficio
The cartridges have some small pcb mounted. Excerpt of a mail describing the findings:
The cartridge has a counter PCB. Mounted to the PCB is a M24C01WP
EEPROM from STMicroelectronics, wired for chip address 1 (A0
connected to VCC, A1 and A2 connected to GND).
A connector with 2 mm pin spacing is used to connect the PCB
to the printer electronics.
The connections are:
Pin Signal
--------------
1 GND
2 SDA
3 SCL
4 +5V
5 GND
6 GND
Please note, when flashing the cartridges, there seems to be a serial number encoded into it. You may have to change this. For example for the EEPROM dump available here has the serial number A7270102061.
A hexdump of it looks like this:
00000000: 30 01 01 03 14 01 01 00 64 00 ff ff ff ff ff ff 0.......d.......
00000010: 32 30 31 30 30 31 20 41 37 32 37 30 32 30 36 31 201001 A72702061
00000020: ff ff ff ff ff ff ff ff ff ff ff ff 64 ff ff ff ............d...
00000030: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ................
00000040: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ................
00000050: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ................
00000060: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ................
00000070: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ................