BATC Forum

There are currently many ex-video-conference cameras appearing on auction sites as corporate systems are upgraded from cabled analogue video cameras to IP cameras connected via PoE. Sometimes they come with a base unit, sometimes not. The base unit may be useful but often it is not well suited to amateur TV use. In most cases the camera and base are designed to be separable to facilitate installation. That means all we need to do to use just the camera is build an interface.

The video output and DC input are available on the connectors. Most seem to be 12V and S-Video or component video. What about the pan/tilt/zoom/focus/iris?

Thanks to Noel G8GTZ for pointing out the Sony PCS1600 video conference system cameras use a standard VISCA protocol.
Following that tip, 5 minutes in Google revealed a Sony installation manual that helpfully details the connector pinout and the protocol which is actually just packetized data sent via RS232. Google also came up with software implementation libraries and both free and paid for applications implementing the VISCA standard and others.

Connections

They Sony system I have uses a 15 way DB15 connector - that's the one with two rows, not the VGA version.

All that needs to be done on the hardware side is to make up connectors for power, video and RS232. You need a Female DB15, a Female DB9 and connectors for S-video and power. I used a standard 4 pin S-video connector and DC jack. Here are the connections:

1 - S-Video Intensity (Y) Mini-DIN pin 3
2 - Y GND Mini-DIN pin 1
3 - S-Video Colour (C) Mini-DIN pin 4
4 - C GND Mini-DIN pin 2
5 - S-Video screen
6 - RS232 GND DB9 Pin 5
7 - RS232 RXD DB9 Pin 3
8 - RS232 TXD DB9 Pin 2
9 - 12V (it takes about 1A when moving, 300mA when not)
10 – 12V - NC
11 - Power GND
12 – IR Remote - NC
13 – RS232 Pin 4, DTR – not sure this is needed
14 – GND - NC
15 – GND - NC

There are 5 ground pins (5, 6, 11, 14, 15) which are all connected together. The same with the two 12V pins (9, 10). I only wired one 12V and power ground. I used pin 5 for S-video cable screen and pin 6 for RS232 ground as that kept the cable bunches together.

I am using an Easycap to capture the S-video. With the above connection you should get video out of it. Note it is a 12V supply, not a 13.8V supply. Some people forget. It will probably be OK, but why risk it.

Software

The control is via a USB-RS232 adapter.

There is a library, libVISCA written by Damien Douxchamps. It is meant for posix systems and if you don't know what that means, chances are you will have trouble using it on Windows so ignore it. There are also applications. The commercial ones e.g. https://www.serialporttool.com/GK/ptz-controller/ These often come with a time limited free-trial which is handy for testing.

There is really good freeware windows application called SimpleCam by OBS user DCStrato.
available here https://drive.google.com/drive/folders/ ... sp=sharing

See https://obsproject.com/forum/threads/pt ... 504/page-2 for details. This app should get you going.



Summary, future plans

Hopefully this is useful. At least is documents the connections. Martin, G4FKK is perhaps, maybe, possibly considering thinking about developing a microcontoller based solution.

Dave, G8GKQ is not currently planning on adding this to Portsdown, so don't ask.

Meanwhile I am investigating doing the same thing with the Polycom cameras that appear similar. Anyone experimenting with Polycom cameras it would be good to hear experiences, especially if successful. The obscure, dense 40 pin connector is available on AliExpress. Incidentally, the Polycom 12V uses a 2.5mm x 5.5mm barrel connector but with +12V on the outside so take care.

If you want to test a camera, then there is a software application which will give you a free 30 day trial (bit expensive to register though! cheaper to buy a Chinese universal controller joystick/keyboard!)

https://www.ptzcontroller.com/

It has been a lot of years since I last did much with VISCA, but the Sony VISCA protocol is fairly straight forward.

Communication speed either: 9600 bps or 38400 bps
Data bits : 8
Start bit : 1
Stop bit : 1
Non parity

Full technical details of the VISCA protocol can be found here:

https://www.sony.net/Products/CameraSys ... 100121.pdf

8x = Camera address, so camera 1 would be 81, camera 7 would be 87
Broadcast address = 88
At the end of the string, there must be a terminator sent, which is FF

Basic commands:

Lens Control:
Zoom + = 8x 01 04 07 02 FF
Zoom - = 8x 01 04 07 03 FF
Focus FAR = 8x 01 04 08 02 FF
Focus NEAR = 8x 01 04 08 03 FF
Focus Stop = 8x 01 04 08 00 FF
Zoom Stop = 8x 01 04 07 00 FF

Auto/Manual focus toggle = 8x 01 04 38 10 FF

Pan and Tilt:
Up = 8x 01 06 01 VV WW 03 01 FF VV: Pan speed 0x01 (low speed) to 0x18 (high speed)
Down = 8x 01 06 01 VV WW 03 02 FF WW: Tilt speed 0x01 (low speed) to 0x14 (high speed)
Left = 8x 01 06 01 VV WW 01 03 FF
Right = 8x 01 06 01 VV WW 02 03 FF

At the receipt of a valid movement command, the camera will normally keep moving until a STOP command is recieved
Stop = 8x 01 06 01 vv ww 03 03 FF

In PIC Basic, a command example to ZOOM + for camera 1 would be:

HRSOut $81,$01,$04,$07,$24,$FF
Followed by a stop command (when the zoom button is released):
HRSOut $81,$01,$04,$07,$00,$FF

VISCA support all sorts of bells and whistles, but the above is probably all you'll need to control a shack camera.

Hope this helps.

73s,

Jason G7KPM