This morning I connected my Linux PC directly to the mount (using the FTDI USB/TTL adaptor) and from a terminal sent :j1<0D> and received back only the same each time. In fact any command is simply echoed by the mount - obviously because of the Tx/Rx being wired together... but nothing back from the mount.

Then something weird happened.....

I connected my logic analyser to the Rx line to see what was happening and hey-presto I started to see (in the terminal) valid responses from the mount.

From sending :j1<0d> I received :j1<0d> followed by =000080 , which I believe is the current Az position. Other commands also produced valid responses. As soon as I disconnected the LA it stopped responding.

I think there is a triggering problem on the front-end of the FTDI USB interface. I see you have an CH340G device.....I need to lay my hands on one of those too and see if that is maybe the secret! (I have a prolific one as well...but that is not working either).

Chip-chip-chip away...

Thanks for the support guys - I'm sure we will get there!

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