Getting started with BG96 and MCU through UART

Knowledge Base Serial
1

Hi,

I have the BG96 development board and I managed to connect it to an MCU through UART, The thing is that everytime I turn OFF and ON the DevBoard the BG96 seems to be “freeze” and won’t answer to any AT command until I press the PWRKEY button on the board.

After pressing the button I recieve:

RDY

APP RDY

and after that it will answer to my AT commands.

Is there something I forgot to configure? or I have to do that “manually” everytime I want to use the AT command after any ON/OFF situation?

PS: The only data I found about, is that I have to set the baudrate to the one of the MCU and save it, but it still does the same (AT+IPR=115200;&W)

2

  1. pls use MCU GPIO connect with BG96 powerkey pin， and give it a 500ms low level pulse .

  2. do you means that AT&W does not work ?

3

Option number 1 works perfectly, but I understood that by setting AT+IPR=desiredBaudrate;&W it wont be necesary to do the PWRKEY pin start.

4

UPDATE:
I managed to control the BG96 through UART with another CPU.

But this last days when I turn it ON after sending the APP RDY message it starts sending non-sense.

Here I leave what I get after after turning it ON with the PWRKEY:

>>init
initializing BG96

RDY

APP RDY

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Does anyone has an idea of what’s happening or how to solve this?

PS: “init” is a command I programmed on my MCU tu turn the BG96 ON, it only “press” the PWRKEY for a period of time until it’s on.

5

try AT\r\n not init …

6

AT\r\n works perfectly. My problem is on the “turn on” of the device.

My MCU works as a bridge between the PC and the BG96. So when I send “init” to the MCU, it turns the BG96 PWRKEY low for 500ms so the BG96 turns on, BUT when it turns on it sends:

RDY

APP RDY

And after that it sends all the non-sense I posted before, to the MCU.

7

try re-flash module… it happened to me but i don’t remember what it was

8

How can i do that?

Or you mean re-flashing the MCU?

9

module - BG96…
it seems like bad uart remaping

10

Hi pablopabota ,

pls set Uart baudrate as 115200,

for more analysis , pls send email to support@ quectel.com, thanks

11

I have the same issue with BG96, how can I resolve it?

12

It is rate match issue , Pls connect BG96 to PC directly to check that , if this phenomenon still be there .

You know that Sometimes the crystal vibration of MCU is very unstable

13

Hi,
I also have a need to connect the BG96 to a Host MCU with no luck. To test this independently I’m connecting the uart1 to the PC directly via., a TTL to USB adaptor (3.3 V). However the module still dont respond. I have seen done garbage printed

Where as there is no issue with the USB-AT cmd port. Only the UART1 is having issue.
I have set the baud rate to 115200

How to troubleshoot this further ?

14

@pablopabota
can you please share the source code and scemetic file of your implementation.
I also want to communicate with BG96 using reneses controller over uart interface,
it will me good refernce for my implementation.

Thanks & Regards,
Bhavin