Exar USB Serial Driver

Version 1B, 1/13/2017 Fixed Bug: The conditional logic to support kernel 3.9 was incorrect (line 396 in xr_usb_serial_common.c).

Version 1A, 1/9/2015

This driver will work with any USB UART function in these Exar devices: XR21V1410/1412/1414 XR21B1411 XR21B1420/1422/1424 XR22801/802/804

The source code has been tested on various Linux kernels from 3.6.x to 3.17.x. This may also work with newer kernels as well.

Installation

• Compile and install the common usb serial driver module

  make

  insmod ./xr_usb_serial_common.ko

• Plug the device into the USB host. You should see up to four devices created, typically /dev/ttyXRUSB[0-3].

Tips for Debugging

• Check that the USB UART is detected by the system

  lsusb

• Check that the CDC-ACM driver was not installed for the Exar USB UART

  ls /dev/tty*

  To remove the CDC-ACM driver and install the driver:

  rmmod cdc-acm

  modprobe -r usbserial

  modprobe usbserial

  insmod ./xr_usb_serial_common.ko

Technical Support

Send any technical questions/issues to [email protected].