connect with usb to COM-NB-IOT-MODULESIM7020G fails
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 Hi, 
 I cant get the USB port on sim7020g modem working. I just connect my PC with a terminal emulator.
 The board powers up (red led) and blinking blue NET LED.
 However I only get garbage characters on my terminal as if the speed was wrong.
 I have tried all speeds without success. Default is 115200 8N1.It generates 2 USB-devices as other modems like SARA R410 do. 
 Should it be possible - any clues ?Olav 
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 Hello @olavk I assume you mean the USB port on the green board plugged into the COMX.NB-IoT module, correct? If yes, then according to the SIM7020G Hardware Design Guide - chapter: 1.4 Functional Overview the USB port is meant for debugging. Maybe that means it cannot be used to issue AT commands? Thanks 
 Felix
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 Thanks @felmue - Yes I mean the USB on the breakout board. The referred manual states : 'The SIM7020G contains a USB interface compliant with the USB1.1 specification as a peripheral'. 
 And my intention was indeed to do debugging to see if the modem would connect to the network with my SIM before I start to connect it to my Arduino.Anyone that have a connection diagram for how to connect this breakout-board to an Arduino (MKR Zero), 
 as I don't want to use the M5 Stack wrapping.So I have pins PWR, GND and P/G on one side and VIN VEXT and VTTL on the other side. 
 Could I expect P/G to be the pin to trigger to power on/off ?
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 Hello @olavk no, I don't think P/G is the on/off trigger. It seems to be connected to GND. I think PWK is the power key. Have a look at the COMX schematic. You'll find this: - 
P/G : is connected to GND 
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GND : is connected to GND 
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PWK : is connected to EN 
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RXD : is connected to GPIO17, GPIO0 or GPIO17 
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TXD : is connected to GPIO16, GPIO5 or GPIO15 
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VIN : is connected to either 5.4 V or whatever is provided at the DC in 
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VIN : dito 
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VTTL : not connected 
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VEXT : not connected 
 How exactly this translates to an Arduino MKR Zero I cannot tell. I don't have one to try. Sorry. Thanks 
 Felix
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 Thanks @felmue, 
 I have now got the card powered by following your observations :
 connecting 5v to VIN, GND to GND, TX to RXD, RX to TXD
 I don't need to trigger PWK to get the modem operational.
 The modem don't connect to the network, but that's another problem..
