search

bvanheu / stratatools

Stratasys EEPROM tool
BSD 3-Clause "New" or "Revised" License
88 stars 40 forks source link

Exception: cannot copy scratchpad #29

Open didonatoandres opened 8 years ago

didonatoandres commented 8 years ago

Hi.

By using BusPirate, I've managed to read the cartridge and decode the information. Then I tried to generate a new binary for my cartridge.

But when I try to write it, I get the following exception: Exception: cannot copy scratchpad, scratchpad is (binary bytes, ending in many 0xFF's) but i sent (binary bytes, none of them is 0xFF's)

Have you seen this happening before? Thanks

didonatoandres commented 8 years ago

I add some new information: By using the argument -p, I tried to replicate the original cartridge. Then, I compared the original hexdump with the new hexdump. Surprise: different. Suprise again: trying to write the original or the replicated binary file, they both lead to the same exception cited above: cannot copy scratchpad, scratchpad is.............

bvanheu commented 8 years ago

hmm I never heard of someone having this problem before.

What is the family code of the chip you are using?

didonatoandres commented 8 years ago

It doesn't seem to be a commercial IC, yet it responds perfectly to 1W. Code is made up of three fields, set up in rows:

331101 0905B1 020AC

It has two wires, just as Dallas/Maxim commercial DS2431

It is mounted on a plastic case as shown in the image (Model is uprint). img_1771a

New things I've been doing:

a) I've tried another cartridge, and result is the same, so it is not a particular cartridge.

b) I could write the cartridge using the serial diagnostic terminal on the printer, but there's a limit: apparently after six write cycles, writing is not allowed and the error message is: " "PClassMaterial.cpp:163:INFO:Cartridge communication error:material write fail limit of 6 exceeded on Model cartridge" I can't tell if this "count" is being made by the cartridge itself or by the PC. I'd bet it's the former.

c) Further testing: insisting on writing with 1W through Bus Pirate, I decided to ignore the exception editing the Python script, and tried to write the whole memory. It can be seen that after writing, the memory content is the same that it had previous to be written. So actually no bytes are being written at all.

All these make me think that this IC is a little more complex than the plain old 2431.

fsabbatini89 commented 6 years ago

Hi didonatoandres, did you manage to write to this memory?

didonatoandres commented 6 years ago

Hi. Not really, but I could find out a little more. Just us I thought, uprintSE cartridges are not exactly a DS2431, they're something more similar to this: https://www.maximintegrated.com/en/products/digital/memory-products/DS28E01-100.html

While writing through the "DIAG" serial terminal, writing was limited to 6 times.

Now, writing directly to the IC was not possible to me. This guy uses a SHA engine, so even though reading works just as the usual 1Wire protocol, writing is a bit more complicated. I guess that everything you need to solve this thing is inside the hard drive of the printer, but the thing is our printer just died for other reasons, so I've lost the interest in working on it.

Good luck.