Access, read and/or write data on unknown chip

Hello. I have a Xerox 3025 cartridge 'chip' which has an IC on it that says:
53D9F
Q421

Chip itself has 4 connections marked as GND CLK DATA and VCC. I was wondering if any of you know how I could read (and later write, if possible) data off it using an Arduino. I read somewhere that SPI library would help, but I've never used it before.

Right now I connected VCC to 3.3V, GND to GND, CLK to pin 13 and DATA is left unconnected because I don't know where it belongs.

That would be a complete waste of your time. IF the chip is memory, it may not even be writable!

Buy an EEPROM chip like the 24LC256 and read/write data to your heart's content!

I don't need this chip as memory for Arduino. I want to reset it, because buying a new chip after every cartridge refill is a waste of money.

dainiusb:
I don't need this chip as memory for Arduino. I want to reset it,

Do you know what data to write to it to cause a reset?

That question assumes it is technically possible to write to it in the first place. But if they don't want you to reset it why would they waste money on a re-writable chip?

If you really do want to try to access the chip read-up how SPI and I2C work. They are not especially complex.

...R

Robin2:
Do you know what data to write to it to cause a reset?

That question assumes it is technically possible to write to it in the first place. But if they don't want you to reset it why would they waste money on a re-writable chip?

If you really do want to try to access the chip read-up how SPI and I2C work. They are not especially complex.

...R

I could find out what data to write by reading a brand new chip.

I do realize that it may be unwritable, but want to read data off it anyways. As seen in this Xerox 6128, 6130 & 6140 chip resetter reprogrammer - YouTube video, there is some hope.

I'm stuck with SPI where it says that there are supposed to be MOSI and MISO connections while there's only DATA on chip. Do I connect DATA to both MOSI and MISO on Arduino or something?

The otherwise completely unhelpful video indicates that it is an I2C chip, not SPI.
Try the I2C address scanner program.

I would if I knew how to connect it all up.

Sounds like you need to do some pretty basic reading on I2C.

For some additional very amusing reading, google "reverse engineer xerox cartridge chip".

jremington:
Sounds like you need to do some pretty basic reading on I2C.

That's what I was trying to suggest in Reply #3 :slight_smile:

...R

I think I got it to work. Now I need to dump all the data off it but for that I need to find out the size of it's memory without erasing(if that is even possible) existing data. Any ideas?