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EHS8 ASC0 problem | Telit Cinterion IoT Developer Community

February 11, 2018 - 2:43am, 2705 views

Hi there,

Just building a new design with an EHS8 and I'm having issues with getting any communications to it.  It is connected to a simple microcontroller, running at 1.8V (the EHS8 is at 4V).  I apply power to the module and drive the transmit line high.  I then see SYSLOADING and SYSSTART from the module (at 115K baud) and send it 'at' at 9600 baud for it to autobaud.  However I get no response from the module at all. I've tries sending 'ATE1' to make sure echo is on but also had no reply.

I'm using Auto On (which is permanently tied to ground) and power ramps up to the module in well under 1ms (I note that for a permanently grounded auto-on power ***** to be ramped in less than 10ms according top the datasheet).

This is the second module I am trying and both are behaving the same way.  Any ideas?  They couldn't have been programmed to ignore the ASC0 lines could they?

And just for note, CTS0 and RTS0 are open.  Schematic attached.  Note that I've not added any or the sim hardware yet.

EHS8 Scematic