Uart wifi module



I have few modules like this, but not sure where and why I got it.




And found ou tit's a HLK RM04 module. the data are from here:
http://www.hlktech.net/product_detail.php?ProId=40

it's a ralink chip inside:


manual and tools are here:
http://www.hlktech.net/download.php?CateId=2

config tool is an AT command tool...
 I have connect the module with a USB to Serial on the DB connector, but it does not work...
of course, there is no chip on the back for this function.....



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