On Fri, Jul 30, 2021 at 4:09 PM Jeffrey Walton <noloader@gmail.com> wrote:
I purchased a OBDLink SX (https://www.amazon.com/gp/product/B005ZWM0R4). The device uses a FTDI chip. I'm having trouble communicating with it. Commands like ATZ\r hang. I've tried using raw terminals (cfmakeraw) and existing terminals (tcgetattr).
Here's what I see in the logs:
[ 1965.676799] traps: process-mbox-re[4668] general protection fault ip:7fb027b65870 sp:7ffcb7640940 error:0 in libc-2.31.so[7fb027aed000+178000] [19699.167543] usb 1-14.1.3: new full-speed USB device number 14 using xhci_hcd [19699.289442] usb 1-14.1.3: New USB device found, idVendor=0403, idProduct=6015, bcdDevice=10.00 [19699.289448] usb 1-14.1.3: New USB device strings: Mfr=1, Product=2, SerialNumber=3 [19699.289451] usb 1-14.1.3: Product: OBDLink SX [19699.289455] usb 1-14.1.3: Manufacturer: ScanTool.net LLC [19699.289457] usb 1-14.1.3: SerialNumber: 113011099400 [19699.300623] ftdi_sio 1-14.1.3:1.0: FTDI USB Serial Device converter detected [19699.300686] usb 1-14.1.3: Detected FT-X [19699.301830] usb 1-14.1.3: FTDI USB Serial Device converter now attached to ttyUSB0
I'm beginning to wonder if I have a driver issue. I found a document https://www.ftdichip.com/Support/Documents/AppNotes/AN_220_FTDI_Drivers_Inst.... The document is confusing me. It says the FTDI chip needs VCP driver support to get a device assigned like /dev/ttyUSB0. But then it says to unload the VCP related drivers (ftdi_sio and usbserial).
Here is what lsmod is telling me:
$ lsmod | grep -i -E 'usbserial|ftdi|d2' ftdi_sio 61440 0 usbserial 53248 2 ftdi_sio,ch341
I'm currently using Ubuntu's 5.4.0-80 kernel. But I would also like to use Fedora's 5.13.5-200 kernel.
My question is, what should we be doing to communicate with a FTDI converter? What driver do we need nowadays?
Cancel... The existing Linux drivers are fine. I needed to use 115200, 8N1 (instead of 38400, 8N1). Jeff