No, I did not change wiring.c. Your current is really low but can you please check if the Arduino is also really working? I could also get these low currents but it appeared that the internal resistance of my multimeter was too high to let the Arduino start!

See also: https://forum.arduino.cc/index.php?topic=622051.0

Yes, I know, but there are more IC’s on that board: encription, charger, arduino, etc. and they too should have a low sleep currents. So far, I haven’t found anybody to get this board below 1 mA in sleep… (measured from the LiPo current).

Sleep or deepsleep gave the same power consumption, so I only use sleep.
Switching modem off to conserve power it worked best to switch of power to the modem: digitalWrite(SARA_PWR_ON, LOW);
It reduces current to about 1.2 mA during sleep, this is a bit disappointing. Do you achieve lower values?

@Martijn-Kooijman Probably linked to certain values that did not occur these days (low values were causing problems for me). Also your double messages problem should be gone now.

No, I haven’t checked downlinks yet, so far I didn’t need them.

I also tried this with a nice struct, tried char* or uint8_t*)&msg,… and also got now and then huge messages for no reason. Depending on the first values I got everything right or nothing in the rest of the variables. So I changed it to:
payload[0] = (byte) ((temperature_coded & 0xFF00) >> 8 );
payload[1] = (byte) ((temperature_coded & 0X00FF) );
etc… (temperature is a 16 bit value)
and send payload directly, never bogus or double messages anymore! Important to declare payload as: char payload[size]
It could be a SAMD issue, just try it and let me know if it solves your problem.

@Martijn-Kooijman I think you may have a problem with the data packing. You probably defined a String datatosend, then datatosend=(const char*)&payload; where payload is an array of several bytes of data you want to send (like with TTN)? It goes nuts sometimes, but not always, so you may think it works but it is not correct, even if you have declared it with attribute((packed)). Solution: just send an int array (After AT+USOST=…).

No, antenna plug seems fine, still 30% message loss this afternoon.

Update: the UFL antenna connector may not have been tightly connected, it was angled up a bit. It seems that these connectors soon develop some play after some light use. I will update you if this solved it.

It surprized me that several messages did not arrive because I had good results with the Sigfox implementation of IoT (if reception was good). @Stefan-de-Lange : So I will look into COAP, do you have some advice to get me started?

@Martijn-Kooijman Yes, I had the same problems, took me a few days to improve it but I am still not satisfied. At first it seemed to run fine with 6 s delay after a SARA power up and reset, but messages sometimes were crazy long (never sent that), or skipped. A 30 s delay did give improvements. But, even after a 30 s delay a message may not arrive (about 1 in 10 in Allthingstalk). I do have the modem set to NB, to speed things up, but still it is slow. Today I increased to 35 s but no further improvement, still some messages are skipped. I am sending every 15 min 6 bytes, sometimes there is only one message in an hour! Reception is perfect. So my hope would be that a new firmware would make it faster.

@Stefan-de-Lange
Yes, there seem to be test solder pads that belong to the SARA chip, but nowhere mentioned what they are (there are 6 of them). I prefer to wait for a serial pass through update such as tested by: https://forum.arduino.cc/index.php?topic=628808.15 Problem seems that it is difficult to get the update file from Ublox (they only provide the USB flash update).

@Stefan-de-Lange said in Arduino MKR NB1500: lukt niet om te verbinden.:

AT+USOCR=17,7000

Regarding the modem firmware update: I contacted Arduino and their hardware team is working hard to release instructions and the proper files to do the update. However they cannot mention a release date yet. Let’s hope for a fast release!

@Stefan-de-Lange Thank you so much, it works now! My message appears at the IoT dashboard or T-Mobile.
The joke is that I bought these modules last Friday, and updating the modem seems very difficult. I would need to do that using a pass through AT+ command method. I will contact Arduino for that. Thanks a lot again! Bert

AT+USOST=0,“172.27.131.100”, 15683, 11, “48656c6c6f20576f726c64”

werkt ook niet.

@Stefan-de-Lange said in Arduino MKR NB1500: lukt niet om te verbinden.:

AT+USOST=2,“172.27.131.100”,15683,11,“48656c6c6f20576f726c64”

AT+USOST=0,“172.27.131.100”,15683,11,“48656c6c6f20576f726c64” werkt dus niet!

@Stefan-de-Lange said in Arduino MKR NB1500: lukt niet om te verbinden.:

AT+NSOST=0,“172.27.131.100”,15683,11,“48656c6c6f20576f726c64”

Ik bedoelde dat AT+NSOST=0,“172.27.131.100”,15683,11,“48656c6c6f20576f726c64”

een error geeft, ik kies dan NSOST socket nummer op basis van terugmelding van AT+USOCR=17, 7000 in dit geval was het 0.

@Stefan-de-Lange said in Arduino MKR NB1500: lukt niet om te verbinden.:

AT+USOCR=17,7000 (message +USOCR: 2)

Helaas, geeft +CME ERROR: Operation not allowed

correctie: Sara R4