CheckEEPROMValid() always fails

[Kiogora]

CheckEEPROMValid() does the following check:

deviceSelect = eeData[10] & 0x0040;

which fails, but the data in the EEPROM is actually correct when parameters are extracted. I have this verified by checking the extracted parameters. As noted on the endianness issue in #31 , My data for eeData[10] in both big and little endian is 0x9904 and 0x0499 non-respectively, but this check will always fail.

Without documentation of this EEPROM for address 0x240A in the datasheet, it is difficult to know the cause of the failure. Maybe it is meant to be:

deviceSelect = eeData[10] & 0x0004?

0x0499 is also present within the EEPROM data in the xlsx file in this repository, meaning the same check would fail when extracting sample parameters.

[slavysis]

Hello,

Actually with both endiannesses it should pass. The complete code is:

int CheckEEPROMValid(uint16_t *eeData)
{ int deviceSelect; deviceSelect = eeData[10] & 0x0040; if(deviceSelect == 0) { return 0; }

 return -7;    

}

When the EEPROM data is valid the function returns 0.

[learning88]

Hello, my eeData[10] =0x04CD,what can i do?

[Kiogora]

@slavysis Thank you for the reply. I did look into the code suficiently. I notice the eeData[10] value in the MLX90640 example data.xlsx that you committed has eeData[10] =0x04CD, my eeData[10]=0x0499, @learning88 eeData[10] =0x04CD .

These cases seem to have a pattern, any insight is appreciated

[slavysis]

Hi, The encoding at this address is going to change so that check will be modified or removed in the future versions of the driver. Apparently @learning88 already got new devices. You should simply remove the if statement in the MLX90640_ExtractParameters() function. The code should be something like this:

int MLX90640_ExtractParameters(uint16_t eeData, paramsMLX90640 mlx90640) { int error = 0;

    ExtractVDDParameters(eeData, mlx90640);
    ExtractPTATParameters(eeData, mlx90640);
    ExtractGainParameters(eeData, mlx90640);
    ExtractTgcParameters(eeData, mlx90640);
    ExtractResolutionParameters(eeData, mlx90640);
    ExtractKsTaParameters(eeData, mlx90640);
    ExtractKsToParameters(eeData, mlx90640);
    ExtractCPParameters(eeData, mlx90640);
    ExtractAlphaParameters(eeData, mlx90640);
    ExtractOffsetParameters(eeData, mlx90640);
    ExtractKtaPixelParameters(eeData, mlx90640);
    ExtractKvPixelParameters(eeData, mlx90640);
    ExtractCILCParameters(eeData, mlx90640);
    error = ExtractDeviatingPixels(eeData, mlx90640);  

return error;

}

@Kiogora I am pretty sure that eeData[10] = 0x0499 in the example data that I committed. So this is the same value as the one that you are getting and this value should return error = 0 and it should work just fine in your case.

Best regards

[Kiogora]

@slavysis Thanks for this. I do confirm that the data in your xlsx file is 0x499, sorry for the mixup. The function works well. I shall now close this issue.