hoangsonk49
Newbie level 2
Hi all,
I'm trying to communicate with SIM900A via MCU but I got a problem of starting SIM900A by using pulse.
- Here is the schematic View attachment Hw-RechargingSimcard-Mainboard.pdf
- Here is my project View attachment SIM900.Nhson.rar
Some description:
- MCU communicates with SIM via USART2
- My PC only can debug MCU via USART1
- According to the schematic, PWRKEY of SIM900A is controlled by CTRL_GSM_PWR_ON/PA7 of MCU
- I use a LED to check the output of CTRL_GSM_PWR_ON (pulse to start SIM900A) and it is OK
- By using simulator, the output of PA7 is correct
But nothing happened with SIM900A, it is not working. I'm pretty sure it is not because of the hardware. Please help if you have any idea for this.
Thank you very much!
I'm trying to communicate with SIM900A via MCU but I got a problem of starting SIM900A by using pulse.
- Here is the schematic View attachment Hw-RechargingSimcard-Mainboard.pdf
- Here is my project View attachment SIM900.Nhson.rar
Some description:
- MCU communicates with SIM via USART2
- My PC only can debug MCU via USART1
- According to the schematic, PWRKEY of SIM900A is controlled by CTRL_GSM_PWR_ON/PA7 of MCU
- I use a LED to check the output of CTRL_GSM_PWR_ON (pulse to start SIM900A) and it is OK
- By using simulator, the output of PA7 is correct
But nothing happened with SIM900A, it is not working. I'm pretty sure it is not because of the hardware. Please help if you have any idea for this.
Thank you very much!