Not rechargeable battery use for Sara SFF and AFF

I make a demo GPS device with Sara SFF , and AFF (N211 rev2) and I have some problem.

I want use this battery type with 3.6 V cell voltage for my project, but when I connect the battery + to te 3.3 Volt and to the below GND the module send 1.4-1.6 volt to my server and the GPS won’t work well. [When I connect the battery to the left side Battery + GND nothing is happening]

I want to debuging this devide at runtime. I want see the variable values and more in real time [I use VS2019 and Visual Micro] but I am willing use sany other free software for debuging.

Used board pins: right and top


1: What is the best soldering pin for the unrechargeable batteryes, and can use the usb and unrechargeble battery at same time?

2: For making box and more, i need for a fritzing file and 3d modell for these boards. Can I download it from anywhere?

3: Can debug these device on the soldered micro usb, or this use only programing this device?

4: Do you need some hardware debugger and if so what do you suggest for all sara device?

Thanks in advance.

Hi @Istvan_Granoviter,

1: Remove the solderjumper to prevent battery recharge.
Best pins are Battery and GND.

2: We are working on it, but I can’t tell you when it’s ready. Should be soon!

3: You can debug via USB in software use SerialUSB.print or via D0/D1 Serial.Print

4: When using the Serial debugging on D0/D1 you need a serial to usb converter.

Best regards,

Hi Jan.
Thanks for your answews.

For answere 4.: The variable value prints via serial is not enought. I want make a normal debugging accross JTAG or SWD with GDB. Remember i have AFF (not just SFF) for developing. I want to buy a hardware debugger but i don’t know wich is working fine and won’t really expensive. Maybe the next one?:

We will change the dev. devices to 412 so the hardware debugger must work on all sara AFF , SFF devices.

The GDB:

For answere 1.: Remove the soldering jumper need only for usb + unchargable battery using same time? Only for useing unchargeble battery dont need remove the jumper? (on unchargable battery test, my device wont work correctly :sob: )

My new question : The sara shut down when [chargable] battery is under 3.4V can i programing sara to drain all type of battery to 2.7V?

Thanks in advance.

If the Serial output isn’t enough a SWD debugger is required. In the office we use an Atmel ICE.
Other SWD Programmer also may work.

It isn’t required to remove the zero-ohm resistor, just for safety. It disables the recharge capability.

In the office we often use the 3.6v saft batteries, we really like them. But we usually use two of the 14500 to be able to provide the max pulse for the sara module.

No, it’s a hardware cut off.

Best regards,

Hi Jan.
Thanks for your answares!
Could you help me with what solredable or pluggable adapter they use to connect the atmel-ice to the Sara board?
I want to use same solution with your company.

I found the solution with tag-connect cable. This solution is very expensive. Does anyone know cheaper chinese solution?