[Connor]

in reply to: No data from CM4 ADC chip SPI #15601

“RCM->RPC = 0x1002” Is a stability improvement that prevents large inducive spikes from erroneously affecting the MCU reset circuit. It is good to have in general, but unrelated to this issue. The LPSPI1 register settings in the “Exit” section of the System Start Block are the relevant ones.

On a FCS1.1 with CM4, the end of the boot config should look like this:

gpio=4=op,pd,dl
gpio=45=pu
dtoverlay=spi1-3cs
dtoverlay=spi0-2cs
dtoverlay=dwc2,dr_mode=host

For FCS1.2 with CM4:

gpio=20=op,pd,dl
dtoverlay=spi0-2cs
dtoverlay=dwc2,dr_mode=host

• This reply was modified 1 year, 5 months ago by Connor.

[Connor]

in reply to: No data from CM4 ADC chip SPI #15599

A couple things to try:

On the MCU side, see if temporarily disabling MCU<>MPU SPI helps, which can narrow down the problem. You can check to make sure that the MCU SPI tristates are set to floating when not transmitting, which will help with interference with other SPI devices on the same bus. The current MCU samples have the tristate setting code in the “System Start” block in the “Hardware Modules Config” subsystem.

On the MPU side, make sure you’re comparing the CM4s on the same FlexCase to isolate the problem to the CM4. Assuming the two CM4s have different behavior on the same FlexCase, double check that /boot/config.txt has the same GPIO/SPI settings for both CM4s, and try the updated Python script in the ADC guide (checks all channels, may have to change the bus index if using FlexCase 1.1).

[Connor]

in reply to: CAN Terminating Resistors (for CM4) #13135

By default, we ship the MCU CAN without resistors, and we ship the CM4 adapter CAN with resistors, but there is some variation in both depending on customer requests. To be sure, a multimeter will confirm if the 120ohm resistance is present across the CAN pins.

If desired for your application, we can also post instructions on how to de-populate or re-populate the internal resistors yourself, keeping in mind that this modification will void the warranty. It is generally recommended to build termination into the wire harness instead of on the devices unless the network layout is simple (short distance, 2-3 devices).

[Connor]

in reply to: How To Send pwm Wave？ #12801

For motor control, you can use the PWM output block (FTM PWM Config) to control the effective voltage level going through the motor. The duty cycle inputs (0.0-1.0) indicates what percentage of the time the output is activated. If you only need one speed for the motor, you can also use the regular output block (GPO Write). In the DIO tutorial, the first PWM output is switching the pin between floating and ground, and so the digital input it is connected to can read two different levels.

Is the diagnostic buzzer not working in the DIO example specifically? Have you verified that the buzzer works with the MCU software that was on the board by default?

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[Connor]

in reply to: How To Send pwm Wave？ #12642

We have added an option for uploading, please upload photos as needed.

If you are trying to create a square wave, it may be easier to use regular digital out.

When you ran the unmodified DIO program, was the wire harness setup the same as in the DIO tutorial? Did the diagnostic buzzer act as expected based on the tutorial?

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