Monitoring /dev/nmea breaks monitoring interface


I find that if we use /dev/nmea to get GPS data with le_fdMonitor, it seems /dev/nmea blocks and legato timers only expire if /dev/nmea reads are completed. So if /dev/nmea (echo ‘$GPS_STOP’ > /dev/nmea) is stopped, then entire fdMonitoring interface dies completely (no timers expire etc). Sample code below, the timer fires every second then again 1ms later then repeats… instead of every 500ms. Im not sure if /dev/nmea blocks, or if problems sharing /dev/nmea with USB and positioning Service… but for me I can;t find reliable way to get RAW NMEA data, unless I drop fdMonitor from /dev/nmea. Anyone had a similar experience?

printf(“Component Init\n”);

le_timer_Ref_t timerPtr3 = le_timer_Create("500ms second timer");
le_clk_Time_t interval3 = {0, 500000};//secs,microsends
le_timer_SetInterval(timerPtr3, interval3);
le_timer_SetRepeat(timerPtr3, 0); //0 mean indefinately.
le_timer_SetHandler(timerPtr3, &timer1Secs);

LE_INFO("Opening /dev/nmea for GPS");
int nmeafd = open("/dev/nmea", O_RDWR);
int flags = fcntl(nmeafd, F_GETFL, 0);
LE_INFO("Flags = 0x%x",flags);
fcntl(nmeafd, F_SETFL, flags | O_NONBLOCK);
flags = fcntl(nmeafd, F_GETFL, 0);
LE_INFO("Flags = 0x%x",flags);
write(nmeafd, "$GPS_START", 10);
LE_INFO("Creating Monitor for /dev/nmea");
LE_INFO("Monitor Created");


Hi @fpereiraEWC, is it possible to send to us the logs when the issue has happened?

Hi mehdiALL

Since this ticket was added, we have moved from WP85 to WP76, this problem does not happen on WP76. If I go back to WP85 I’ll be sure to get a log again.