EEPROM read fail

Just got my kit this week and am eager to get it up and running. Been following along on the forum and am impressed with this great community.

I am using GC 1.10 (and latest Maslow firmware and BBTD frame and quite possibly the ugliest temporary sled) and am trying to get through the calibration steps. I just noticed however, that I’m getting this “error: EEPROM read fail: Using default settings.” message upon boot.

Then I run the test motors action and my left motor fails according to the screen, although I can see the chain moving in both directions.

So, possibly two problems (maybe should have started a second thread) are concerning me. I’ve checked cable insertion, power is connected to Maslow shield not Arduino, my port is connected. Any other things to check? Thanks for your help.

Oh - I’m also getting this in my log, but since I haven’t made it through the calibration completely I figure that this one might be justified:

Message: Unable to find valid machine position for chain lengths 0.00, 0.00 . Please calibrate chain lengths.

Is the EEPROM just used for the calibration values? Or does it also store the Maslow firmware?

That is not good. Did you check all connectors?
What do you meen by

with the test motor? There should be no chains attached for the test I think.

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I just double checked the connectors - they appear to be seated well.

I have been letting the chains dangle from the sprockets on the motor (as well as the bungee) for now, and the sled is not connected. I find that seeing the dangling chain end rising and lowering when running the motor test gives me some measure of satisfaction. :nerd_face:

I have unplugged the shield board from the Arduino, just to inspect, thought I had seen something shorting across two pins of the one chip, but don’t see it now. I’ll give it all another go.

By what measure does GC determine “pass” or “fail” for the motors (since motion isn’t enough to grant a passing grade)? I guess there is some feedback provided by the motor that isn’t matching expectations? Maybe after I try it all again, if it still fails I can swap the cables and see if it follows the cables or sticks with the motor…


I’ve reconnected my electronics and I no longer get the EEPROM read failure message. Maybe there was something shorting it. Additionally, the both left and right motors are now passing the motor test.

However, when I attempt the chain calibration step – sprocket to high noon adjustment-- the sprocket moves both CW and CCW, maybe toggling seven times between the two directions. I’ll search the forum to see if others have had a problem with sprocket alignment.

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Hello @Becca, and welcome!

:grin::100: I enjoy it too. Later, with the chains attached, enjoy the sled testing version of the dance

Each motor has an ‘quadrature encoder’ inside the black end cap. The encoder sends pulses that tndicate the speed and that direction that the motor shaft is turning. The ‘Test Motors’ in GC runs one motor at a time at full speed for a short time and looks at the resulting pulse trains to see if the shaft turned in the proper direction and sent somewhere in the right ballpark of the right number of pulses.

‘EEPROM read failure’ message means that when the Arduino reset, the Maslow firmware looked at the values it keeps stored in the EEPROM and didn’t see the correct validation check flag stored there. This is normal the first time that the Arduino and GC have ever communicated as in your case. The firmware responds by using default values to populate the EEPROM, and after that the message doesn’t arise.

Were you able to use the various buttons to move the sprockets CW and CCW? Do the sprockets move in the expected directions, or have I misunderstood? Try it with chain hanging on the sprocket, the movements are small and the weight of the chain may make them seem less random.

to pass it must see activity from the encoder when it moves the motors, so if
there is motion, but the test fails, check the encoder on the back of the motor
and make sure nothing has damaged it (as well as checking that the connectors
are seated well at both ends)

Thanks for the background info. I might need to read a bit more about the encoders (but maybe while I’m watching Maslow cut out my new sled).

I’m glad that the EEPROM read failure was a one-time (or initialization only) thing.

As for the motor movement during the sprocket alignment, none of the six choices for either motor gets the chain to move noticeably. But I decided simply to accept my sprocket alignment (the teeth were close) and to move on to attaching the sled. Extending the chain worked, although I could have used a bit more slack for ease of install. And my sled looks to be in the center of the sheet!