a question about 4 X DiSEqC Switch

[rockchang]

can anybody tell me what kind of signal does receiver generates to controll diseqc switch?? how does the swith knows which port the receiver want to use??

thanx a lot!

 

[BGonaSTICK]

Hey, you know that's an excellent question, and if you get an answer, I'll be fascinated to read it.

The diseqc 'instruction set' for want of a better name has evolved over the years with the progression from 1.0 to 1.1 and more notably 1.2.

This has given rise to greater funtionality (as you are probably aware).

I think 1.0 just sent information to select one of four available 'positions' which is used to control switching between 4 different LNB's whereas 1.2 can do so much more. I don't have a clue what V2.0 has over 1.2.

A diseqc command can be anything from three to eight bytes in length, and an example would be (in Hexadecimal) E0 31 6E E1 38 (being 5 bytes) though I couldn't tell you what that means in English!

From what I understand, you can have different types of commands such as 'Goto angular position', 'Goto satellite position', 'Drive motor East/West (stepping)' and 'Store satellite position'.

I would like to know (like you) how this data is sent to the motor (or switch) i.e. how it is modulated, and onto which carrier. All I can say is that it's obviously a digital signal based on the nature of the data being sent.

STICK

P.S. Nice post.

 

[Llew]

Hey, you know that's an excellent question, and if you get an answer, I'll be fascinated to read it.

The diseqc 'instruction set' for want of a better name has evolved over the years with the progression from 1.0 to 1.1 and more notably 1.2.

This has given rise to greater funtionality (as you are probably aware).

I think 1.0 just sent information to select one of four available 'positions' which is used to control switching between 4 different LNB's whereas 1.2 can do so much more. I don't have a clue what V2.0 has over 1.2.

A diseqc command can be anything from three to eight bytes in length, and an example would be (in Hexadecimal) E0 31 6E E1 38 (being 5 bytes) though I couldn't tell you what that means in English!

From what I understand, you can have different types of commands such as 'Goto angular position', 'Goto satellite position', 'Drive motor East/West (stepping)' and 'Store satellite position'.

I would like to know (like you) how this data is sent to the motor (or switch) i.e. how it is modulated, and onto which carrier. All I can say is that it's obviously a digital signal based on the nature of the data being sent.

STICK

P.S. Nice post.

If you've got a few hours to spare, read these specifications offered by the originator of the Diseqc system:-
http://www.eutelsat.com/satellites/4_5_5.html

Llew

 

[BGonaSTICK]

Nice one Llew, that's just what I'm going to do (sorry, I didn't mean that to rhyme, but I'm sure as hell not going to change it either!).

One thing I'd really like to create is a standalone application that will allow diseqc control from a Windows platform, and over an IP network. The only problem is that it has to be tied into a specific hardware driver AFAIK. I can't think of any way around it, yet! An API under Linux might be interesting though as well...

 

[Simba27]

If you've got a few hours to spare, read these specifications offered by the originator of the Diseqc system:-
http://www.eutelsat.com/satellites/4_5_5.html

Llew

Thanks for posting that link. I found some of those documents quite informative. Paritcularly the "Positioner Application Notes".

Phil.
(Computer Nerd)

 

[rockchang]

If you've got a few hours to spare, read these specifications offered by the originator of the Diseqc system:-
http://www.eutelsat.com/satellites/4_5_5.html

Llew

Llew ,
thank u for the website you have given us,
its wonderful, I have downloaded all the pdf files and i will read it carefully when i am free~~

 

[Llew]

Nice one Llew, that's just what I'm going to do (sorry, I didn't mean that to rhyme, but I'm sure as hell not going to change it either!).

One thing I'd really like to create is a standalone application that will allow diseqc control from a Windows platform, and over an IP network. The only problem is that it has to be tied into a specific hardware driver AFAIK. I can't think of any way around it, yet! An API under Linux might be interesting though as well...

There are a couple of driver circuits shown in the PDF's, one being a slave driver working up to Diseqc 1.2. This would mean programming an OTP, but finding the source code might be difficult.
An easier circuit using a PIC is also shown, but there may be not enough Diseqc commands available to make it worth building. Still, it might make a good 'starter' project for you to while away a few winter evenings.

Llew