2016-01-27 06:49 PM
I have an STM32L4 Discovery board that I'm trying to use as a USB host.
Looking at the schematics, I can see the EMIF02-USB03F2 device that is used in conjunction with the USB lines, but it would appear to me that the PD1 and PD2 (that are connected with the pull-down resistors that indicate that this is a USB 'host') are not connected.Is the schematic correct? If so are we supposed to make any hardware corrections to add the pull-downs?Also I can't get the Vbus to power up (at least as evidenced by the green LED6 lighting up) UNLESS I set the pin PC9 to be a digital output with a '0' value (which of course is then not controlled by the USB firmware). As this needs to be powered (so that a high-speed device can pull-up the D+ line), is there a bug in the firmware in the STMCubeMX libraries?Finally, I'm ultimately wanting to use the USB host port for some headphones for audio in and out. I can see some references to sending audio out through the USB connector, but is there an example somewhere is using it as an audio input?Susan