Ulp file s3 line checksum calculate

[tontito]

hi how to calculate ulp file s3 line cheksum

def calcCRC16X25(self, data: str):
    if len(data) & 1:
        return ["BE", "EF"]
    byteData = []
    for i in range(0, len(data), 2):
        byteData.append(int(data[i:i + 2], 16))
    crc = 0xFFFF
    for i in range(0, len(byteData)):
        crc ^= (byteData[i] & 0xFF) << 0
        for _ in range(8):
            if crc & 0x0001:
                crc = (crc >> 1) ^ 0x8408
            else:
                crc = crc >> 1
    print(f'CRC: {crc}')
    crc = crc ^ 0xFFFF
    return ["%0.2X" % (crc & 0xFF), "%0.2X" % ((crc >> 8) & 0xFF)]

S38580080200BB34D3BF0000000065A9C6AC50CEF3CBA3AB00AE52EFF1EA5543F646FA1A591F060BA50E205C835988432B465D16FE13CE7A6D7F2F1D8C18E2B241B7C5F266F7E4914794754AD64F92428942077D83EDE27899175363B79C326C460CA7644C940212161DFB1C70836206E999C70ED301B20559F5133E675E823F66C067201C4F6E

calculate this line

S3 85 80080200 BB34 D3BF0000000065A9C6AC50CEF3CBA3AB00AE52EFF1EA5543F646FA1A591F060BA50E205C835988432B465D16FE13CE7A6D7F2F1D8C18E2B241B7C5F266F7E4914794754AD64F92428942077D83EDE27899175363B79C326C460CA7644C940212161DFB1C70836206E999C70ED301B20559F5133E675E823F66C06720 1C4F 6E
this line crc16/x-25 checksum 1C4F but this code result : 0CB2

how to calculate ulp s3 line checksum calculate?

[16D]

This line is from CANsniffer during teletransmission?

[Barracuda09]

This online calculator comes to the same result: B20C Calc, Probably you need to add more data for the checksum?

So that makes me believe that the Python CRC16/X25 calculation is correct.

[tontito]

Hello, I am uploading the PSA ECU ULP update file to Google Drive. In the Cal calibration files, the checksum result at the end of short lines is correct, but in the ULP files, the checksum we calculate does not match the one at the end of the lines in any case. Online CRC calculations and your code are correct, but the checksum at the end of the lines is different. I have included the files as examples.

This file is the original update file for the Citroen C5 Aircross ECU, obtained via the official diagnostic tool, Diagbox.

https://drive.google.com/file/d/1CSryg8Z0Jj6J5ZgZtjOOY_kogBWT8YQA/view?usp=drive_link

[Barracuda09]

It almost makes me think, there is no CRC16/X25 in the .ulp file at all. And that it should maybe calculated at the moment it is send?

Did you retrieve the file from the temp directory that Diagbox uses?

[tontito]

Yes, I copied it from the temp folder while updating diagbox online.

[16D]

I should try record teletransmission of some module but not with vlud adapter (don't record commands send to module). I think you prepare wrong line to send. Read this carefully:
https://github.com/ludwig-v/arduino-psa-diag/blob/master/UDS_FLASH.md

[16D]

Here is teletransmission sniffed and used file:
https://drive.google.com/file/d/1lqIojDtwjQUDC9VtnpGIggbAxyoh-yGf/view?usp=drive_link
teletrans.txt

[tontito]

What I want to do is to make changes in the ulp file and turn off immo or egr. Here is the sample file, I can find the checksum2 of the immo line, but I cannot match the checksum part with your codes, CRC-16/X-25

https://drive.google.com/file/d/1fa6_TikgxGA56FY_h1UER_kkvuSBfjQx/view?usp=drive_link

[16D]

I think this is other checksum like in this link:
https://github.com/ludwig-v/arduino-psa-diag/tree/master?tab=readme-ov-file#content-data

[tontito]

I think this is other checksum like in this link: https://github.com/ludwig-v/arduino-psa-diag/tree/master?tab=readme-ov-file#content-data

I already did this by trying. The short one is s2, but it does not work on long lines or s3 lines.

[Barracuda09]

How do you know what to change in the ulp file to disable that? by Disassemble?
Does this file not not download or is there some other problem or you are trying to make a download program?

Sorry, I do not know what you are trying todo here