# Legato serial Communication FX30S **URL:** \ **Category:** Uncategorized\ **Created:** [May 18, 2018, 7:19am UTC](https://forum.legato.io/t/legato-serial-communication-fx30s/3287 "2018-05-18T07:19:36Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![baiticpruebas](https://avatars.discourse-cdn.com/v4/letter/b/f475e1/32.png) [@baiticpruebas](https://forum.legato.io/u/baiticpruebas)\ **Post date:** [May 18, 2018, 7:19am UTC](https://forum.legato.io/t/legato-serial-communication-fx30s/3287/1 "2018-05-18T07:19:36Z")
Hello! Is it any chance of create a legato app that permits serial communication? We have already created a program with le\_tty functions (le\_tty\_open, le\_tty\_close,…) but we cannot use the ports ttyHS0 or ttyHSL1 properly. The app runs and the port seems to be opened correctly, but on a Windows with hyperterminal we are not receiving the message. Regards, Pablo ---
**Author:** ![jyijyi](https://sea1.discourse-cdn.com/flex019/user_avatar/forum.legato.io/jyijyi/32/822_2.png) [@jyijyi](https://forum.legato.io/u/jyijyi)\ **Post date:** [May 18, 2018, 8:28am UTC](https://forum.legato.io/t/legato-serial-communication-fx30s/3287/2 "2018-05-18T08:28:50Z")
did you set AT!MAPUART correctly? ---
**Author:** ![baiticpruebas](https://avatars.discourse-cdn.com/v4/letter/b/f475e1/32.png) [@baiticpruebas](https://forum.legato.io/u/baiticpruebas)\ **Post date:** [May 18, 2018, 9:06am UTC](https://forum.legato.io/t/legato-serial-communication-fx30s/3287/3 "2018-05-18T09:06:11Z")
I think so. The output of the AT!MAPUART? command is this: " AT!MAPUART? !MAPUART: 17,17 OK " As i see in other topics, this is the correct output that permits the use of the ttyHS0 port. Is this correct? ---
**Author:** ![jyijyi](https://sea1.discourse-cdn.com/flex019/user_avatar/forum.legato.io/jyijyi/32/822_2.png) [@jyijyi](https://forum.legato.io/u/jyijyi)\ **Post date:** [May 18, 2018, 9:27am UTC](https://forum.legato.io/t/legato-serial-communication-fx30s/3287/4 "2018-05-18T09:27:30Z")
I don’t have FX30S, instead I try attached UART echo application on UART2 on my MangOH green board, it is working fine. Maybe you can have a try.[UART\_Test1.rar](https://forum.legato.io/uploads/short-url/7GAe5TKCqNh9ba8LjyLBlQbn1KK.rar) (77.2 KB) I am using legato 16.10.4. ---
**Author:** ![baiticpruebas](https://avatars.discourse-cdn.com/v4/letter/b/f475e1/32.png) [@baiticpruebas](https://forum.legato.io/u/baiticpruebas)\ **Post date:** [May 18, 2018, 11:57am UTC](https://forum.legato.io/t/legato-serial-communication-fx30s/3287/5 "2018-05-18T11:57:27Z")
Thanks a lot! I tried with that application in my FX30S (after migrating to a Legato application), but it doesnt work. It seems like the program read once (but i dont wrote nothing) and then gets freezed waiting for new bytes to read: May 18 11:51:02 | prueba[1219]/pruebaComponent T=main | pruebaComponent.c \_pruebaComponent\_COMPONENT\_INIT() 118 | UART\_TEST May 18 11:51:02 | prueba[1219]/pruebaComponent T=main | pruebaComponent.c echo\_test() 33 | before read() May 18 11:51:02 | prueba[1219]/pruebaComponent T=main | pruebaComponent.c echo\_test() 38 | read 1 bytes == May 18 11:51:02 | prueba[1219]/pruebaComponent T=main | pruebaComponent.c echo\_test() 33 | before read() I am also using that version of legato. ---
**Author:** ![jyijyi](https://sea1.discourse-cdn.com/flex019/user_avatar/forum.legato.io/jyijyi/32/822_2.png) [@jyijyi](https://forum.legato.io/u/jyijyi)\ **Post date:** [May 18, 2018, 2:10pm UTC](https://forum.legato.io/t/legato-serial-communication-fx30s/3287/6 "2018-05-18T14:10:20Z")
Yes, you need to type something on uart2 with buad rate 115200 and see if the application can receive the data. I am not quite sure if fx30s is using uart1 ot uart2. ---
**Author:** ![baiticpruebas](https://avatars.discourse-cdn.com/v4/letter/b/f475e1/32.png) [@baiticpruebas](https://forum.legato.io/u/baiticpruebas)\ **Post date:** [May 21, 2018, 8:24am UTC](https://forum.legato.io/t/legato-serial-communication-fx30s/3287/7 "2018-05-21T08:24:07Z")
Hi again! It seems that the error is solved. Your code is totally correct. The problem was that I updated de FX30S firmware wrong. Now, with the firmware obtained from [https://source.sierrawireless.com/resources/airlink/software\_downloads/fx30-firmware/fx30-firmware/](https://source.sierrawireless.com/resources/airlink/software_downloads/fx30-firmware/fx30-firmware/), i can see the ttyHSL0 port and then is possible to use it in your program. Now works like a charm. Thanks a lot!