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printer_cartridge

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printer_cartridge [2017/09/14 09:47] – add implementing cartridge chip kingkevinprinter_cartridge [2019/04/15 06:12] – [identifying cartridge chip] update link kingkevin
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   - the family code (last byte of the ROM ID) "0xb3" (decoded from the trace) doesn't match [[https://github.com/owfs/owfs-doc/wiki/1Wire-Device-List|common lists]] (mTC002 it a for a thermocouple. a different manufacturer might have used the same family code)   - the family code (last byte of the ROM ID) "0xb3" (decoded from the trace) doesn't match [[https://github.com/owfs/owfs-doc/wiki/1Wire-Device-List|common lists]] (mTC002 it a for a thermocouple. a different manufacturer might have used the same family code)
   - the function commands present in the trace (0x0f, 0xaa, 0xa5) [[http://owfs.sourceforge.net/family.html|match]] a couple of devices   - the function commands present in the trace (0x0f, 0xaa, 0xa5) [[http://owfs.sourceforge.net/family.html|match]] a couple of devices
-  - the [[https://www.maximintegrated.com/en/products/digital/memory-products/DS2432.html|DS2432]] matches the usage: 1-Wire (the protocol used) EEPROM (to store the toner level) with SHA-1 authentication (to prevent counterfeit cartridges). The [[http://datasheets.maximintegrated.com/en/ds/DS2432.pdf|Maxim datasheet]] is abridged and does not contains family code and function command codes (lame security by obscurity), but the [[http://pdf.datasheetcatalog.com/datasheet/maxim/DS2432.pdf|Dallas datasheet]] does+  - the [[https://www.maximintegrated.com/en/products/ibutton/memory-products/DS2432.html|DS2432]] matches the usage: 1-Wire (the protocol used) EEPROM (to store the toner level) with SHA-1 authentication (to prevent counterfeit cartridges). The [[http://datasheets.maximintegrated.com/en/ds/DS2432.pdf|Maxim datasheet]] is abridged and does not contains family code and function command codes (lame security by obscurity), but the [[http://pdf.datasheetcatalog.com/datasheet/maxim/DS2432.pdf|Dallas datasheet]] does
   - based on this datasheet I implemented a DS2432 protocol decoder for sigrok, and the capture matches (no bytes missing or exceeding, and the commands order make sense). Only the family code does not match: 0x33 for DS2432, 0xb3 for our chip   - based on this datasheet I implemented a DS2432 protocol decoder for sigrok, and the capture matches (no bytes missing or exceeding, and the commands order make sense). Only the family code does not match: 0x33 for DS2432, 0xb3 for our chip
   - even the used SHA-1 hash implementation used for authentication matches (I re-implemented and tested it with key material I found later)   - even the used SHA-1 hash implementation used for authentication matches (I re-implemented and tested it with key material I found later)
printer_cartridge.txt · Last modified: 2024/01/07 17:49 by 127.0.0.1