Battery issue

[pierre marsot]

Posted on June 05, 2018 at 09:24

Hi everyone,

I'm working on B-L072Z-LRWAN1 lora discovery kit and i have an issue.

I'm able to upload my program on STM32 and it run when the STM is plug in on USB STLINK.

My issue is when i want run my STM on 3AAA battery. 

I just have the LD7 LED and my program (send data with LoRa) seems to not working ...

Have you an idea ?

Thanks

PS : i use the EndNode Cube default project 

#battery #lora

[Jirka Pospis]

Posted on July 10, 2018 at 16:26

Same problem here, using SW4STM32 and latest ST-Link firmware (I thought it could help as indicated in

https://os.mbed.com/questions/68969/STM32F429I-DISC1-can-not-be-powered-by-u/

 ). Seems like MCU is blocked without USB host connection.

Thx for any advice.

[Jirka Pospis]

Posted on July 10, 2018 at 16:41

Ok, the problem is RESET pin as mentioned in UM2115: 'If the board is supplied by CN13, by battery or by CN11, SB37 must be removed to release the RESET pin managed by ST-LINK. In that case the ST-LINK is no more powered.'