FX30S serial read locked

IoT Modules WP Series
1

After updating legato to version 19.11.5 my application stopped reading the serial port, following code used:

    const char *serialPort = "/dev/ttyHS0";
	int port = le_tty_Open(serialPort, O_RDWR |O_NOCTTY);
	le_tty_SetBaudRate(port, LE_TTY_SPEED_9600);
	le_tty_SetRaw(port, 1, 2);
	//le_tty_SetFlowControl(port, LE_TTY_FLOW_CONTROL_NONE);
	char *parity = "N";
	le_tty_SetFraming(port, *parity, 8, 1);

	do {
		char buffer[1024];
		int readSerial;
		readSerial = read(port, buffer, sizeof(buffer)); // this line is stuck

Port permission is configured:

device:
	    {
    		// read and write acess to the UART2 port.
    		[rw]	/dev/ttyHS0	/dev/ttyHS0
    	}

Does not generate any error in the log, it just gets stuck!
Has anyone experienced this problem?

2

Hi Anderson,

There was an update in the FX30 base release in which driver for UART1 was changed. The tty for UART1 is now:
/dev/ttyHS1
Please try changing to this tty.

Thanks,
Ian

3

The ttyHS1 port does not exist on the device:

`Feb 12 09:20:59 fx30s user.err Legato: =ERR= | supervisor[11868]/supervisor T=main | app.c 
SetCfgDevicePermissions() 777 | Failed to set permissions (rw) for app 'fx30sSerialMqtt' on device /dev/ttyHS1'.`

The available port is still ttyHS0 according to the command below

root@fx30s:~# ls -la /dev/ttyHS0 
crw-rw----    1 root     dialout   248,   0 Dec 31  1969 /dev/ttyHS0

I also tried to map ttyHS0 to ttyHS1, but it gets stuck in the read function

`[rw]	/dev/ttyHS0	/dev/ttyHS1`
4

Did you set the uart1 to be data mode in at!mapuart ?
You can also try to disable auto suspend mode before running your app

5

For reading data through the RS232 port, what is a valid UART configuration?

(Service to map to a UART)
• 0—UART disabled
• 1—AT command service (Note: Not available for UART2)
• 2–3—Reserved
• 4—NMEA service
• 5–15—Reserved
• 16—Linux Console
• 17—Customer Linux application
(Physical UART)
• 1—UART1 (Default)
• 2—UART2

6

You should use

17—Customer Linux application