# Drivers UART-USB **URL:** \ **Category:** Legacy AirPrime modules\ **Created:** [August 13, 2014, 2:44pm UTC](https://forum.sierrawireless.com/t/drivers-uart-usb/7383 "2014-08-13T14:44:59Z")\ **Posts on this page:** 10\ **Page:** 1
**Author:** ![fredda11](https://avatars.discourse-cdn.com/v4/letter/f/5f8ce5/32.png) [@fredda11](https://forum.sierrawireless.com/u/fredda11)\ **Post date:** [August 13, 2014, 2:44pm UTC](https://forum.sierrawireless.com/t/drivers-uart-usb/7383/1 "2014-08-13T14:44:59Z")
Hello i got the Q26xx dev kit ([estore.sierrawireless.com/airpri … \_data=Home](http://estore.sierrawireless.com/airprime_q_series_development_kit?ec_trk=followlist&ec_trk_data=Home)). I’m trying to connect to my computer by connecting to the UART1 on the board and a USB addapter to my computer. But when I try to connect via tera term to COM4 (Mobile broadband device) i can’t connect. And when i look in the drivers I have a serial-USB device that don’t have any drivers and I have tried to install drivers but I can’t get it to work. Anyone that has any suggestions? ---
**Author:** ![mlw](https://sea1.discourse-cdn.com/flex025/user_avatar/forum.sierrawireless.com/mlw/32/3706_2.png) [@mlw](https://forum.sierrawireless.com/u/mlw)\ **Post date:** [August 13, 2014, 3:20pm UTC](https://forum.sierrawireless.com/t/drivers-uart-usb/7383/2 "2014-08-13T15:20:24Z")
Fredda, I just want to confirm your scenario. - Q26xx dev kit - Q2686? - USB to serial cable connected to your PC, what com port does this enumerate to? It will not be a Mobile Broadband Device, rather a straight com port. Once you have determined the above com port that would be the initial step. After this - Does the Flash\_LED come on when you power the board? Then subsequently start flashing? If it flashes it means the unit is atached to the network, if it is solid on it means the unit has powered up and is not on the network for soem reason (there are alot of reasons this could be). - When you power the board can you see the CTS line toggle (measured on the dev kit pin or use a terminal which shows you the status)? Regards Matt ---
**Author:** ![fredda11](https://avatars.discourse-cdn.com/v4/letter/f/5f8ce5/32.png) [@fredda11](https://forum.sierrawireless.com/u/fredda11)\ **Post date:** [August 14, 2014, 7:05am UTC](https://forum.sierrawireless.com/t/drivers-uart-usb/7383/3 "2014-08-14T07:05:59Z")
Hello, I just want to confirm your scenario. - Q26xx dev kit -Yes - Q2686? -No it is the Q2687 - USB to serial cable connected to your PC, what com port does this enumerate to? It will not be a Mobile Broadband Device, rather a straight com port. I have serial connected on the board and USB in my PC. So when i open tera term I have a COM5 that that doesn’t say any more, is that the one I shoulld connect to? But when I connect to that I only get ERROR in response. -The Flash-LED come on and after a few seconds it start flashing. So i looks like it is working. What is the CTS line? ---
**Author:** ![mlw](https://sea1.discourse-cdn.com/flex025/user_avatar/forum.sierrawireless.com/mlw/32/3706_2.png) [@mlw](https://forum.sierrawireless.com/u/mlw)\ **Post date:** [August 14, 2014, 7:20am UTC](https://forum.sierrawireless.com/t/drivers-uart-usb/7383/4 "2014-08-14T07:20:41Z")
Sounds like com5 is the one you want, send the following to it (making sure the serial port is set to 115200bps 81N as teraterm defaults to 9600) at+cmee=1 ati at+cpin? at+cgmr at+cops? at+creg? at+cgreg? Regards Matt ---
**Author:** ![fredda11](https://avatars.discourse-cdn.com/v4/letter/f/5f8ce5/32.png) [@fredda11](https://forum.sierrawireless.com/u/fredda11)\ **Post date:** [August 14, 2014, 7:50am UTC](https://forum.sierrawireless.com/t/drivers-uart-usb/7383/5 "2014-08-14T07:50:41Z")
ok, thank you it looks like I almoste have it working. I changed from tera term to PuTTY it works much better. But after about 20 sec I have write a command I get ERROR readring from serial device. This is my settings in Putty: -connected to COM5 - baud 115200 - data bits 8 - stop bits 1 - parity none - flow control none Does it look right? Thanks for youre help. ---
**Author:** ![mlw](https://sea1.discourse-cdn.com/flex025/user_avatar/forum.sierrawireless.com/mlw/32/3706_2.png) [@mlw](https://forum.sierrawireless.com/u/mlw)\ **Post date:** [August 14, 2014, 8:00am UTC](https://forum.sierrawireless.com/t/drivers-uart-usb/7383/6 "2014-08-14T08:00:01Z")
Yes that looks fine, does the unit return error to all the commands I mentioned above? Regards Matt ---
**Author:** ![fredda11](https://avatars.discourse-cdn.com/v4/letter/f/5f8ce5/32.png) [@fredda11](https://forum.sierrawireless.com/u/fredda11)\ **Post date:** [August 14, 2014, 8:12am UTC](https://forum.sierrawireless.com/t/drivers-uart-usb/7383/7 "2014-08-14T08:12:35Z")
No it returns +CME ERROR: 10 for at+cpin?, at+cops? and at+creg?. All the other returns OK. ---
**Author:** ![mlw](https://sea1.discourse-cdn.com/flex025/user_avatar/forum.sierrawireless.com/mlw/32/3706_2.png) [@mlw](https://forum.sierrawireless.com/u/mlw)\ **Post date:** [August 14, 2014, 8:29am UTC](https://forum.sierrawireless.com/t/drivers-uart-usb/7383/8 "2014-08-14T08:29:24Z")
That means the unit cannot see the SIM, without that the unit is limited in what it can do. Reards Matt ---
**Author:** ![fredda11](https://avatars.discourse-cdn.com/v4/letter/f/5f8ce5/32.png) [@fredda11](https://forum.sierrawireless.com/u/fredda11)\ **Post date:** [August 15, 2014, 10:17am UTC](https://forum.sierrawireless.com/t/drivers-uart-usb/7383/9 "2014-08-15T10:17:33Z")
Any idea why it can’t find the sim? ---
**Author:** ![mlw](https://sea1.discourse-cdn.com/flex025/user_avatar/forum.sierrawireless.com/mlw/32/3706_2.png) [@mlw](https://forum.sierrawireless.com/u/mlw)\ **Post date:** [August 15, 2014, 10:22am UTC](https://forum.sierrawireless.com/t/drivers-uart-usb/7383/10 "2014-08-15T10:22:14Z")
Draw isn’t closed properly, you need to slide it shut at a guess. Matt