EnOcean Pi - EnOcean Link - Serial Comms not working

Question

Can anyone help me please?

We are trying to receive EnOcean Serial Packets (ESP3.0) in a Raspberry Pi from an EnOcean Pi (or direct from an EnOcean TCM320).

BUT for some strange unknown reason, not all bytes are received.

Modifying the EnOcean Link "Receive()" function to report received bytes, shows that more frequently than not bytes are missing.

E.g. when multiple packets are sent over the Serial link only some bytes (at best) from each packet are received in the Software (C++) running on the Raspberry Pi which is receiving from /dev/ttyAMA0.

However, occasionally a complete packet is received okay!

A digital Oscilloscope with Serial decoding shows that all bytes are sent okay on the actual wire to the Raspberry Pi!

Can anyone help get this working for us as it is holdig up our project?

Thanks

hkafeman · Accepted Answer

Bryan

Thanks I got a python program based on yours working in one version of Raspberry Pi installation. However it took a lot of modifying to run (as well as installation of a library...) and it showed all bytes received.

The differences might have been v3 versus v2 or some such? The actual installation we are working on for our application did not have python installed for some reason so I did not try it with that....

Anyway we have now found the solution to our original problem. It turned out we had fhem running in the background and that was grabbing some of the bytes....!

We had forgotten that it had been installed following EnOcean's original instructions, when we used it to estabiksh communications working with the EnOcean Pi, before starting to integrate with our own software running on an EnOcean TCM320!

Note however that the EnOcean Link library software is polling the serial port for incoming bytes and taking 95% of the cpu. That does not seem to be an issue so far, but I will try changing it to use blocking serial port read calls and/or to delay a short time in between polls to have less effect on other applications...

Thanks

Henry

hkafeman · Answer

Bryan

Thank you for your reply.

We are actually running our own embedded software on the TCM320 and calling uart_sendPacket() to send ESP3 packets.

The problem occurs with the Raspberry Pi receiving the packets on its Serial Port.

Yes this is working at 57,600 baud.

It seems there is one of the following causing problems as EnOcean have confirmed that there are many users/applications utilising the EnOcean Link software for Serial communications to EnOcean Pi, USB300, etc.:

The build of the receiving software on the Raspberry Pi which uses EnOcean Link (libEOlink.a) - we are currently using Eclipse on a Linux computer.
The configuration of the Raspberry Pi causing issues with the ttyAMA0 serial port.

Thanks and Regards

Henry