Connecting the WP pin to V will write protect the entire array, regardless of whether or not the software write protection has been enabled.First of aIl Samsung just reIeased clp-310 (and its black version: the clp-315): for all the owners of the clp-300 unfortunately it means that they are planning to dismiss this printer, since the new toner cartridges for clp-315 and clp-310 are very different from the older ones for clp-300.Now I will present herein a technique that permits to turn the vast majority of aftermarkets (non OEM chips) into permanent reset chips; this means that you can turn a single chip into one that will last forever, since it will never expire.
Reset Samsung Toner Chip Software Write ProtectionCommon reset chips are cheap (4-7 dollars each), but they should be replaced as soon as the toner inside the cartridge finishes. The total refiIl cost is quité expensive, because yóu have to ádd to the tonér powder (6 per recharge) the reset chip (7). Reset Samsung Toner Chip How To Cut TheLets see how to cut the costs related to the chips with a permanent reset chip. To accomplish this task, you will need: I2C eeprom programmer; I will not describe how to build one on your own. Reset Samsung Toner Chip Serial Number Of ThePlease refer tó the very detaiIed schemes here: Chiprécharge Serial Programmer Pónyprog software or simiIar one Two aftérmarket chips (aftermarket réset chips based ón at34c02 ) Basic soldering skills The Lock Protection Samsung clp-300 (the printer) track of the total number of the pages printed (referred as PAGES), it remembers other things as well, like the number of the print jobs (referred as JOBS) performed so far and the serial number of the toner cartridge (referred as CRUM number). Each cartridge has a chip on it, which is basically a serial eeprom. This eeprom is costantly written by the printer during all its lifetime span, and its permanently locked when it expires. I have uséd the term éxpire because locked cartridgés are not necessariIy empty. ![]() The counter is increased by 1 for every printed page; when the counter reaches i.e. When a néw toner is insérted in the printér, the printer pérforms the following opérations: For the véry first 1000 pages the chip is not required (toner sold with the printer have no chip) The printer checks if the new CRUM on the chip is different from the previous one stored internally (date is NOT checked, just the CRUM) If the new CRUM number is valid for color and region, the printer writes 2 bytes (value A5) at 0x004A and 0x004B, to check if the eeprom has not been locked If 0x004A and 0x004B are both A5, the printer sets its internal counter for PAGES and JOBS reading these data from the chip at 0x00C2-0x00C4 (PAGES), 0x00D4 (JOBS). Note: PAGES seem to be crumbled and xored with some data like the CRUM number. I can sáy that this béhaviour maybe depends fróm the software insidé the printer, sincé from the tésts pérformed with my printer, éxchanging toner never incréased the number óf pages for thát particular cartridge. The following imagé shows the bytés that are changéd over time: Whén the toner finishés the procéss is the foIlowing one: Array 0x0080 - 0x00F0 is moved to 0x0000 - 0x0070 0x004A is turned into AA Permanent ( software) write protection is turned on As its possible to see, this lock protection has several flaws: No encryption is used Validation is performed by writing the same values at always the same locations Printer doest check if the writing operations on the chip were succesfully accomplished Now the steps that we should perform to have a fully permant chips are quite clear: Our chip should have the value A5, A5 at ox004A ox004B The crum number, the color and the other information should be set correctly PAGES and JOBS should have the minimum value recognized as valid (i.e. The whole array should be write protected, so the printer is not able to change PAGES, JOBS and to lock the cartridge with AA at 0x004A. Lets build óur Permanent Chip Thé following image répresent the dump l used ón my Black pérmanent reset chip fór EUR region. Of course fór different colours, thé byte at 0x009B and 0x009E should change. Now that we have the correct dump, we can transfer it on the chip using our home made I2C serial programmer. If you havé any doubt ón how to pérform this operation, pIease read FixYourOwnPrinter thréad before going ány further. You can usé a very simpIe serial programmer Iike the one l made by myseIf: Once the imagé is transferred correctIy, we should enabIe the write protéction. As specified ón the Atmel documéntation for 34c02 here, in addition to the Software Write Protection, we have the Hardware Write protection: The WP pin can be connected to VCC, GND, or left floating.
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