In a production setting, I want to ensure that a calibration table for each IMU actually matches the IMU installed. If a different IMU of the same type is installed, a warning/error is presented.
So I thought it would be a good idea to scan the QR barcode on the IMU and save this into an EEPROM, and somehow extract the same details from the IMU itself. I'm unsure if this is possible though. With one ADIS16460 I have here, the QR barcode reads "102218580184".
Polling the SERIAL_NUM register yields 0x07D1 or 2001, LOT_ID1 is 0x1924, LOT_ID2 is 0x120A . Is there any way these values can be used to evaluate if the QR barcode matches? If no, should I then just forget the QR barcode and instead store the SERIAL_NUM, LOT_ID1 and LOT_ID2 values in EEPROM for the IMU that is calibrated and compare with the readout during startup/configuration of the IMU?
After reading your question, we did some investigation on the ADIS16460 QR Code. We rely on the internal registers for identification and we record the lot numbers into the registers. Therefore, we strongly recommend that you not rely on the QR codes.
The problem with using the QR code on this part is that we hadn't quite settled on s standard with this part was new, so the correct interpretation isn't always the same for every ADIS16460. This has changed on newer parts. For the ADIS16460, I'm told that the first 8 digits correspond to the lot number, but seeing that it's different that the LOT_ID1 and LOT_ID2, I don't know how the lot number is coded into the QR code.
Perhaps you can read and store the QR code in your process, but rely on the register values to uniquely identify a given IMU.
Dear Mr. Kern,
Thank you very much for your reply. I did as you suggested (not to rely on the QR code). The ADIS16460 we have are fairly recent though. The specific IMU comes from a box of 15 pieces from week 18, 2018.I now save LOT_ID1, LOT_ID2 and the SN to an EEPROM once in production and compare with the IMU at runtime. Works perfectly.