I am trying t change the baud rate of sim800l v1. But not successfully happening, every power cycle again going to AT+IPR= 0. I am using the following AT commands for changing the baud rate.

1.AT 2.AT+IPR? 3.AT+IPR=115200 4.AT&W

after power rebooting of sim800L going it is going AT+IPR=0.

Thank you

2 Answers 2


From a quick scan of its AT command manual, I think you want to look at section 1.7.1, "Parameter Saving Mode". There are several modes, and while the description isn't quite clear, it looks like one command causes all subsequent parameter changes to be saved into NVRAM (so they will survive over a power-down), while another one causes the most recently changed parameter into NVRAM. I'm not sure which mode would best serve your needs, but the latter one would appear to answer your immediate need, retaining the baud rate.


Your mistake is using AT&W to save the parameter, for some reason you have to add the profile number which is only 0 and use AT&W0 on a sim800l a sim800c with newer firmware accepts AT&W. I've learnt this the hard way.

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