> mk: don't know how to make 'acm.h' in directory /sys/src/cmd/usb/serial
Sorry, I thought that was already in the distributed version. I've updated the serial.tar file, so it should be complete now if you try again. > And how do I read data (if possible, not through C)? Set the baud rate with echo b9600 >/dev/eiaU?/eiaUctl and then you can receive data with cat /dev/eiaU?/eiaU or set up an interactive conversation, as Steve Simon suggested, with con /dev/eiaU?/eiaU More information is in the manual - uart(3), usb(4), con(3)
