Thanks for both options. I would of liked to have used the software solution but as I plan to sell this product, rather make it easier to just wire up the pin then give consumer cable for powering and then keep a USB OTG cable for debugging.gsh wrote: ↑Fri Sep 21, 2018 2:35 pmIf you're happy with software solution then you can ignore the OTG_ID pin completely and just add dr_mode=peripheral to the dtoverlay line
Otherwise if you want to be able to use the special host cable in the uUSB plug so you can use OTG to switch between host and device then you will need to wire pin 4 on the uUSB connector to the OTG_ID pin on the compute module.
Don't forget to wire a pull up to the HPD (hotplug detect) pin if you're not using HDMI)
I would try with a 10k-47k pull-up to 3.3V. If you now ask yourself 'why the hell is this stupid guy telling me to use 3.3V and not 1.8V or 5V?' than I Need to say (sorry, again: RETUFM): refer to page 12 of the CM users Manual.OTG receptacles and plugs contain a fifth pin, added to the standard four USB pins (VBUS, GND, D+, and D–). This is a fifth pin in the connector, not a fifth wire in the cable. The mini-A plug has the fifth pin tied to its ground pin, and the mini-B plug leaves the fifth pin unconnected. A dual-role device requires circuitry to read the state of this fifth pin (with, for example, the aid of a pull-up resistor) to determine which end of the cable is inserted. The dual-role device receiving the mini-A plug is the default host.
For the cable the USB OTB spec defines RB_PLUG_ID as:
Mini-B plug: 100k Ohm
Mini-A plug: 10 Ohm
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