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EHS5 module ASC1 trouble | Telit Cinterion IoT Developer Community

December 7, 2016 - 8:40am, 6483 views

Hi all!

I use EHS5 module. It is soldered into my board. All works perfectly but I got trouble with ASC1 port.

I use it as RS485 interface  with SN65HDV01 chip. It was no connection and after complete checking of the board my colleague found that TXD1 and RXD1 on the chip are swapped. Really! When I wrote to the port from JAVA-midlet there was no output signal on TXD1  29 pin (directly on EHS5) but I saw this signal on RXD1 30 pin. So I swapped these pins and now my modbus package is successfully reached for my device ( I use external terminal to spy). But anyway there is no response from my device.

Also I'd like to ask how to be with RTS and CTS. CTS of EHS5 is connected to DE pin of RS-485 chip. RTS of EHS5 is on the ground. When I create the connection I use "autocts=off autorts=on".  If I change autocts to "on" there is no output packet from RS-485. Changing the autorts to "on" or "off" makes no influence on the transmission.

So the question  is... Is Gemalto really swapped 29 and 30 pins?  How to adjust the port for RS-485 transmission?

I hope for some help to understand my problem. Thanks.