Hi ALL
how to use J501 micro usb port?
i connect a usb storage but the storage didn’t have power.
J501 micro-B USB is not a host port…it is a device port. Meaning the Xavier does not look for devices like keyboards or mice, but instead provides a device. In this case a serial UART used as a serial console. Your host PC can use a serial communications program with settings of “115200 8N1” and act as a text console (the host PC would have to have an FTDI serial UART device driver, but this is extremely common and most Linux systems will have this already). This requires a type-B connector. Type-A connectors will be inert.
Oddly, when I connect this port to my PC running Windows, 4 serial ports are created! I haven’t been able to detect any output from any of these ports, though.
If you plug it into a linux box, do you get just one serial port?
(I don’t have a computer booting Ubuntu – an Ubuntu VMWare session running on windows has suffieced up to this point).
I’m not sure what Windows will do. It is one FTDI serial device, but how the driver looks at it from Windows is an unknown for me.
I just tried plugging in my Xavier to my work laptop which boots to Ubuntu 16.04, and I STILL see 4 serial ports appear and disappear on my laptop when I connect and disconnect:
tony@ASR-583U:~$ dmesg | grep FTDI
[ 63.341364] usb 1-2: Manufacturer: FTDI
[ 63.361356] usbserial: USB Serial support registered for FTDI USB Serial Device
[ 63.361444] ftdi_sio 1-2:1.0: FTDI USB Serial Device converter detected
[ 63.361582] usb 1-2: FTDI USB Serial Device converter now attached to ttyUSB0
[ 63.361656] ftdi_sio 1-2:1.1: FTDI USB Serial Device converter detected
[ 63.361790] usb 1-2: FTDI USB Serial Device converter now attached to ttyUSB1
[ 63.361822] ftdi_sio 1-2:1.2: FTDI USB Serial Device converter detected
[ 63.362047] usb 1-2: FTDI USB Serial Device converter now attached to ttyUSB2
[ 63.362071] ftdi_sio 1-2:1.3: FTDI USB Serial Device converter detected
[ 63.362290] usb 1-2: FTDI USB Serial Device converter now attached to ttyUSB3
[ 148.635196] ftdi_sio ttyUSB0: FTDI USB Serial Device converter now disconnected from ttyUSB0
[ 148.635635] ftdi_sio ttyUSB1: FTDI USB Serial Device converter now disconnected from ttyUSB1
[ 148.636126] ftdi_sio ttyUSB2: FTDI USB Serial Device converter now disconnected from ttyUSB2
[ 148.636586] ftdi_sio ttyUSB3: FTDI USB Serial Device converter now disconnected from ttyUSB3
Putty won’t connect to these ports on linux either.
Hmmm…interesting! You are right. The FTDI chipset within the UART has four end points. In theory this could do a lot of interesting things, e.g., not just serial console. No serial port can be used for devices though, e.g., this cannot be used for a USB hard drive or keyboard.
Would someone from NVIDIA be able to comment on whether the three ports beyond the serial console port have some future reserved use, or if developers are free to use the spare ports?
Hi,
J501 is designed as a substitute for J503. It gets UART log from ttyUSB3 and the rest are not used.
Hi DaneLLL
thanks for your reply.
i have a question about J30 uart port.
J30 uart1 pin is just a normal uart interface, different with TX1/TX2.
if this information correct or wrong???
Thanks for the clarification! I tried connecting to the last of the 4 ports (ttyUSB3 on the Jetson side) at 115200 bps, and I do indeed see console output at shutdown and boot up.