The debug UART has both the uboot software behind it on boot, and later a linux serial console.
During boot, if your device emits any characters, this will trick uboot into putting up its menu and hanging the boot process. It will be waiting for you to make a menu choice and your device will know nothing of it. Assuming you miss that one second window, plus all the time preceding uboot coming up under power where the uart's fifo will be filled, then you will clear uboot. But this is too much risk. The next phase of the boot has linux hosing its console output to the same debug port, and depending on the linux setup, you may have a serial console come up on that UART also. I do here. So the debug uart port is difficult to use for anything but debug. Use another UART. The device you describe may be using TTL serial, you did not mention RS-232 levels. This should be confirmed. If TTL, your device may still be at a voltage which is too high for the beaglebone to handle. Check the datasheet for 5V compatibility. I doubt its acceptable. If your device is assuredly TTL at 3.3V then it will probably work hardware wise by just hooking up the device, crossing TX with RX and tying GND to GND. The 3 wires you say. Then you have to PINMUX in the UART's TX and RX pins, or pick a UART you know is already pinmuxed out. -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
