# Unable to connect QGC to Pixhawk-4 via USB **URL:** \ **Category:** Using QGroundControl\ **Created:** [April 22, 2022, 6:13pm UTC](https://discuss.px4.io/t/unable-to-connect-qgc-to-pixhawk-4-via-usb/27100 "2022-04-22T18:13:23Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![Pierce\_Nichols](https://discuss.px4.io/user_avatar/discuss.px4.io/pierce_nichols/32/10560_2.png) [@Pierce\_Nichols](https://discuss.px4.io/u/Pierce_Nichols)\ **Post date:** [April 22, 2022, 6:13pm UTC](https://discuss.px4.io/t/unable-to-connect-qgc-to-pixhawk-4-via-usb/27100/1 "2022-04-22T18:13:23Z")
So, I’m using the QGC daily build under Linux, a Holybro Pixhawk-4, and I was able to upgrade the firmware to the latest stable release. I cannot connect via USB. I’ve tried a variety of different speeds without apparent luck. Any ideas what I need to do in order to get this up and running? Edit to add: the I/O power light is steady green, the I/O B/E light is steady red, the I/O ACT light is blinking blue, and the FMU PWR light is blinking very fast green. ---
**Author:** ![Vipin\_Krishna](https://discuss.px4.io/letter_avatar_proxy/v4/letter/v/57b2e6/32.png) [@Vipin\_Krishna](https://discuss.px4.io/u/Vipin_Krishna)\ **Post date:** [April 30, 2022, 5:18pm UTC](https://discuss.px4.io/t/unable-to-connect-qgc-to-pixhawk-4-via-usb/27100/2 "2022-04-30T17:18:25Z")
hi ,did you got any solutions ---
**Author:** ![Pierce\_Nichols](https://discuss.px4.io/user_avatar/discuss.px4.io/pierce_nichols/32/10560_2.png) [@Pierce\_Nichols](https://discuss.px4.io/u/Pierce_Nichols)\ **Post date:** [April 30, 2022, 5:55pm UTC](https://discuss.px4.io/t/unable-to-connect-qgc-to-pixhawk-4-via-usb/27100/3 "2022-04-30T17:55:32Z")
Sort of… I plugged in an FTDI cable and now QGC recognizes both the FTDI and direct serial connections. It’s sub-optimal but works well enough for my purposes.