Developing STM32L432 USB application before our hardware is ready.

[Hamid.Wasti]

I am developing a device based on the STM32L432 processor. It needs to use USB connectivity using Full Speed CDC class. I would like to get the firmware development started using a development board before our hardware is available.

I can not find any development boards from ST for this micro that have a USB port. What other processor's development board can I use that will allow the source code to be easily ported to our board when it becomes available?

The only development boards I found in the STM32L4xx family are based on STM32L476, which has a USB OTG port, while the STM32L432 has a USB Device port.

The development will be done using the STM32Cube L4 Version 1.14.0

Regards,

Hamid

[waclawek.jan]

You can try  NUCLEO-L432KC, DP/DM=PA11/PA12 are brought out to the connector so attaching an USB-B connector using as short connections as possible should be possible and that has high chances of working.

Alternatively, you can use the https://www.st.com/en/evaluation-tools/32f072bdiscovery.html for development, USB should be similar - it has the same device-only USB module, but it may be in slightly different version.

JW

[berendi · Accepted solution]

I would just cut up an USB cable, and solder it directly to PA11/PA12, and the +5V wire to any 5V tolerant GPIO pin. Connect it to the PC through a cheap USB hub.

For a somewhat cleaner solution, get an USB connector. Use short wires < 10 cm, it should be adequate for development purposes.

[Hamid.Wasti]

Thank you both JW and Berendi for your quick responses.

For the last several years I have dealt exclusively with designs with USB High Speed and USB Super Speed where GHz is the basic unit of conversation. I had totally lost sight of the fact that USB Full Speed is only 12MHz, which feels only just slightly above DC when you call it 0.012 GHz!

A cut up USB cable will work just fine for development without any signal quality issues. One can poke their head inside any old desktop computer and see the quality of the cable between the motherboard and front panel USB-A connectors. If that can work reliably, anything can!

Thank you for your time and your insight.

Regards,

Hamid