[chbot] Controlling a pan and tilt head using AMX

[Robin Gilks]

> Hello everyone,
>
> Chocolate fish time...
>
> Just playing with a Fujinon CPT-1A-10DA pan and tilt head, these units
> are used in the broadcast TV arena. It may use the same protocol as the
> EPT-5E series.
>
> Very little documentation supplied with the product, although appear to
> have confirmed that the unit is controlled using RS232.
>
> The manual for a suitable PSU was supplied, so managed to identify power
> and RS232 lines. Dismantled the unit to confirm that RS232 feeds pin 13
> of a MAX232 (R1IN).
>
> After moving the pan channel (by hand) with power removed, the unit
> returns to previous position when 12V is applied; am assuming that the
> unit works OK.
>
> This unit was originally configured by BCL (now Kordia ?).
>
> Managed to find a suitable controller (EOP-102J-30E) on eBay for
> US$1100; would like to borrow it to do some comms sniffing but that
> seems unlikely.
>
> Finally, spotted that the unit sends a short message from it's RS232
> port at power on. Looks like data cells are 200us wide, so maybe a
> 4800baud comms channel. Need to explore this more.
>
> Have found all manner of P&T protocols, some require an address field
> (RS485, or RS232) so that adds a further level of uncertainty/excitement
> to the proceedings.
>
> If anyone has experience with such devices, or know where correct
> documentation might be acquired, I will be most happy to hear from them.
>
> This is not a commercial project, and hair is being pulled out by the
> clump ...
>
> Regards, Mark

Pelco-D sounds like a favourite. It's very common in pan/tilt devices and
is usually RS485 (i.e. balanced) and the default baud rate is 2400bps
(although most devices have a command or DIL switches to set it to what
you want).

This gives  a bit of background
   https://www.commfront.com/pages/pelco-d-protocol-tutorial
and this is a typical device detail
   https://www.epiphan.com/userguides/LUMiO12x/Content/UserGuides/PTZ/3-operation/PELCODcommands.htm
and this is the actual spec
   http://hanjindata.lgnas.com:10000/myweb/P1339/PelcoDProtocolManual_1_1.pdf

-- 
Robin Gilks