SM5100B Shield

Wireless & IoT
1

Hi,

I am trying to get the SM5100B module running that I purchased as a shield. I have it connected to a known stable uC via TTL RX/TX lines.

Am using pins 2/3 off the shield board to communicate with an atmega256.

On reset, the unit outputs the following bytes 5 times:

7E 00 00 00 00 00 08 FE 01 7E

This is at 115200 8N1. I have verified the data with a scope too.

This is a little bit different from what I was expecting… is this the ARM bootloader in the unit or something?

It doesn’t respond to AT commands specified in the PDFs, and I see no mention of this protocol.

Thank you

2

Edit: It is not this… the correct pins had solder flow… does anyone have other ideas?

Turns out that the header was shorted where solder had flowed across several pins during manufacture.

So was probably the download mode always in operation.

Edit: It is not this… the correct pins had solder flow… does anyone have other ideas?