Questions tagged [checksum]

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Tenda router + Firmware-Mod-kit = Firmware header not supported

I have been working hard for over 1 week trying to get a modified firmware installed on a Tenda AC10 V1 router. It is the original firmware with some modifications to unlock extra features. The ...
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2-byte checksum

I cannot figure out what checksum is used for the following communication. As I understand, 450D is the “stop” part. It doesn't change no matter what. And the two bytes before 450D are the “checksum”. ...
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Reverse-engineering a weird 32-bit possibly not CRC checksum

I am trying to decode Arad/Master Meter utility water meter RF transmission. So far, I had success with reading the meter serial number and counter reading. The transmission looks like that: ...
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3 votes
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Is there a software that can reverse calculate checksums by brute force?

For reverse calculation of CRC checksums, there is a pretty nice tool – CRC reveng. I was looking for, and have not found, a similar tool that can do the same for non CRC checksums. For example, using ...
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Finding method for checksum calculation - CRC or XOR or other

I have RF connected devices for which I'm working on the protocol of data packets, as those are not supported by known software at the moment. Packets are pretty simple and consists only in 6 nibbles ...
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CRC can bus message

Does anyone know what the CRC algorithm can be used here? crc:0xE8 data:0x0 0x0 0x0 crc:0x43 data:0x1 0x0 0x0 crc:0x2F data:0x2 0x0 0x0 crc:0x7B data:0x3 0x0 0x0 crc:0xD0 data:0x4 0x0 0x0 crc:0xDA ...
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2 votes
2 answers
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Help with working out a checksum

I'm trying to work out how to reverse engineer the checksum on infrared remote data stream for a heat pump. I've established that it's not a CRC, and I've tried methods found on this forum. It doesn'...
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Reverse engineering 16-bit checksum algorithm for 433Mhz RF remote control

I'm stuck trying to figure out how to calculate the two last checksum bytes (16-bits) of these packets. The remaining data fields are understood, and it is just the two last bytes that I am current ...
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How to modify checksum after making changes in Nokia 215 4G firmware?

If I change any character in the firmware file and try to flash it, it will failed. But it will successfully flashed if I changed the string with the same number of character if it's not a function. ...
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Trying to find a checksum (possible CRC?) algorithm for CAN messages on a Porsche

I have the following problem. Besides CAN itself having a full checksum and stuff in the protocol, I have data sets where the first byte of the CAN message is some checksum generated in some unknown ...
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Is this a checksum/CRC response or cryptography?! Thanks

I've been pointed here from the Cryptography Stack Exchange so hopefully you can help me here! Long version of the story at the end....the short version is... I want to identify this CRC/cipher/crypto ...
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Checksum in CANbus Message

I'm trying to work out the calculation method for a checksum in a CAN message but I'm having some difficulties. I am unsure if there are actually 4 separate checksums, or one big one at the end of ...
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how to calculate a byte value

We are reversing the method of creating a byte array packet. These values are obtained by serialport monitor from mediatek metamode usb port.The values of both packets are changed by changing the imei....
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