Working with Uart and Sim800l

[Prashant Singh]

Hi,

  I am working with nrf52DK and Sim800l, I want to send some data using GPRS commands like AT etc.
I am having a market build module for Sim  www.circuitstoday.com/.../gsm_module.jpg
I am trying to establish a connection using the ble_app_uart example from SDK but I am unable to send AT command.
 Same tried with UART example also.
Connections done are DK pin P0.06 -> Rx of Sim, DK pin P0.08 -> Tx of Sim, given ground and power supply.
Baud Rate used is 115200.
if I am disconnecting TX and RX pin from Sim I am able to see data(AT command) in the terminal.
Any Help would be appreciated.

[awneil]

FYI, the reason your text has been formatted as source code is because you have spaces at the front of each paragraph.

[awneil]

if I am disconnecting TX and RX pin from Sim I am able to see data (AT command) in the terminal.

Sorry, it's not clear what "data" you're talking about - is that the data from the nRF52, or data from the SIM800?

Can you communicate from a PC terminal with the SIM800 using the same connections?

Can you communicate from a PC terminal with the nRF52 using the same connections?

You need to narrow down exactly what is and is not happening.

[Prashant Singh]

Thanks for the info about text, The data here just means commands(AT etc) I am trying to send using ble_app_uart or uart examples to SIM800

[awneil]

Again:

• Can you communicate from a PC terminal with the SIM800 using the same connections?

• Can you communicate from a PC terminal with the nRF52 using the same connections?

You need to narrow down exactly what is and is not happening.

Remember that you are the only one who has access to your hardware. Nobody else can do these checks for you. Also, nobody else can see what is happening in your system, nor how it is connected - so it is important that you provide complete, detailed, unambiguous, and accurate descriptions.

[Arepa]

I think he means that he is able to comunicate from a PC to the external module module using the DK (UART-USB bridge), but not when he is connecting p0.06 and p0.08 to the other module without a PC.