[US/CAN] Cheap Focer 2’s

By the way, here’s the part of the schematic from the v0.9 board that covers the pull-up and pull-down resistors. It suggests 10K resistors. We used 11K (probably the closest thing I was able to find on Ebay). But I worry that 2K will be a pretty stiff pull-down.

Yeah I am not sure if it is a soldering error (no real way to inspect the pads on that package size) a bad batch of IMU’s or just me not using the software correctly.

I do have two of them handy. The third was a 0.9 and it is installed in a board.

I can get one prepared less the pull downs and IMU.

Would you be up for testing those on VESC_Tool? I could plug mine in and make sure we’re doing it the right way. I don’t recall exactly what I had to do, but I recall that it wasn’t immediately obvious.

I have been connecting to the VESC turning the app config to no app.

On the IMU page I select internal IMU. And then after writing the config I turn on imu sampling on the right hand side.

Can you try clicking on the “IMU Data” button here?

Pretty much the same thing.

Perhaps these can’t handle the heat needed to hot air reflow them. The next batch I get should be able to have them soldered (The imu’s were out of stock when I ordered these.)

I used hot-air to solder mine and they did OK. I’ll have to take the deck off my board and see how I monitored them on VESC_Tool.

Great! How should we organize me sending paying you, and sending the board plus an IMU to be soldered to @ziploc?

OK, I just tested an IMU on one of my v0.9 boards. I plugged the CFOC2 into the laptop via the USB cable. Powered the CFOC2. Clicked “Connect” in the app, and then clicked the two buttons shown below. I see yaw, pitch, and roll values streaming when I do that. If you’re doing the same thing and not seeing values streaming, I guess the IMU is not working. I hope it’s not a problem with V1.0 vs. V0.9. Do we know if anyone has built a V1.0 and used the IMU?

I have some boards with MPU9250’s and I think the new ICM that is supported.

Perhaps I will try it out with an external IMU to eliminate me messing up the software side of things.

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I don’t want to put you to a lot of trouble, but it would be great if you could send a board directly to RCJD2001 and save him the time and expense of extra postage. And frankly I don’t have great confidence I’ll make the IMU work if you didn’t. Mine have worked on V0.9 boards, but perhaps there’s been a change.

That being said, I’m more than happy to give it a crack.

Perhaps I can get an external IMU working for him. With a small cable it should stay pretty compact.

How critical are the values for the pulldown resistors?

Typically pull-up and pull-down resistor values are not very critical. It’s common to use 10k to 20k ohm. The schematic for v0.9 calls for 10K. I installed a couple of 11K resistors for him, but then the USPS disposed of his package. :frowning:

He mentioned 2K, but I suspect that might have been a typo. Jonathon, did you want 2K resistors for some reason?

I have can probably find some 10k resistors.

The ones I got are 0603.

Helno, let me know how you’d like to go. If you get it all working - great. If not, you should send the board to the same address you sent mine to a couple weeks ago. I’ll also need an IMU. I’ve got the resistors, so no worry there. If I recall correctly, your shipping method includes tracking and insurance? I think that’s the way Jonathan would like to go this time (which is understandable after what happened to his last one).

I’d be happy to solder the through-hole components to save Jonathan a couple of bucks if you have one like that laying around.

I do have unfinished boards so I can do that to save him some money.

I don’t have any IMU’s left and honestly I don’t know if all I have is bad stock. So perhaps getting something direct from digikey might be a better way to go.

It looks like Mouser and Digikey are out of stock as well. I suggested Jonathan could get a BMI160 from Amazon on the breakout board. I can take it off the breakout board and put it on his board. So I think you should hear from him, ordering a board from you - sent to me.

Sorry for taking way to long to do this but I was able get some free time to confirm this works with an external IMU.

@RCJD2001 if you like I can have an external board mounted pretty low profile on the main board connected to the I/O connector. Not as nice as an onboard IMU but will function the same.

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