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.
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.
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.
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.