EEPROM usage table

WMXZ

Well-known member
Suggest, to have a single place where EEPROM usage is reported (in addition to the Readme file of the libraries).

At the moment I only figured out by reading the code that the Prop shield uses 68 bytes starting from 0x60.

It is not clear to me if there are reserved parts of the EEPROM and what is freely available for own applications.
 
Yes, such notes are important. A WiKi would be a great place for that :)

"Use File > Send Calibration to write the calibration data to Teensy's EEPROM memory" is on the Store page - but not what addresses? I had not seen that before - I wrongly assumed the calibration data went to the NXP device. The Data on the EEPROM wouldn't follow the shield though? Of course putting it on the 8MB Prop flash is even more likely to get erased.
 
Yes, such notes are important. A WiKi would be a great place for that :)

"Use File > Send Calibration to write the calibration data to Teensy's EEPROM memory" is on the Store page - but not what addresses? I had not seen that before - I wrongly assumed the calibration data went to the NXP device. The Data on the EEPROM wouldn't follow the shield though? Of course putting it on the 8MB Prop flash is even more likely to get erased.

Actually, the winbond SerialFlash has "security registers" that could be used to store calibration data and are NOT erased by the normal flash erase sequence, discussed in
https://forum.pjrc.com/threads/33328-Prop-Shield-Beta-Test?p=99608&viewfull=1#post99608

So it is possible (desirable?) to have the calibration data travel with the shield and not the MCU.
 
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So it is possible (desirable?) to have the calibration data travel with the shield and not the MCU.

From my extensive experimentation with the magnetometer, I'd say that it's not useful to have the calibration travel with the prop shield as the ideal calibration will change, depending on the final assembly of the circuit. Nearby PCBs, wires, batteries, usb connectors, etc, all have an effect on the calibration so the calibration should be done after final assembly (on breadboard, pcb, etc).
 
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