Stumped on CM11A protocol...

[pconroy]

If anyone here recalls their code for the CM11A - I've got a question.

I'm confused watching the data coming to the PC from the CM11A.

Suppose, I have a motion detector on M-3. And it detects motion, so I'll expect an M-3 On sequence of bytes.

After sending a 0xC3, I see:
   0x03 ==> number of data bytes is three
   0x02 ==> F/A mask

Then:
   0x0A   ==> cool, it's an address and it decodes to "M-3"

Then:   
   0X02   ==> also fine, that's "M - On".

But then what's this third byte trying to tell me???
   0xa0   ==> it's an Address byte.



Is it the brightness value?
In other words 0xA0/210 * 100%

That doesn't make any sense to me..
I see it for M-3 "Off" too. 
So I'm stumped...

thanks

[Charles Sullivan]

If anyone here recalls their code for the CM11A - I've got a question.

I'm confused watching the data coming to the PC from the CM11A.

Suppose, I have a motion detector on M-3. And it detects motion, so I'll expect an M-3 On sequence of bytes.

After sending a 0xC3, I see:
   0x03 ==> number of data bytes is three
   0x02 ==> F/A mask

Then:
   0x0A   ==> cool, it's an address and it decodes to "M-3"

Then:   
   0X02   ==> also fine, that's "M - On".

But then what's this third byte trying to tell me???
   0xa0   ==> it's an Address byte.



Is it the brightness value?
In other words 0xA0/210 * 100%

That doesn't make any sense to me..
I see it for M-3 "Off" too. 
So I'm stumped...

thanks

You are trying to read too many bytes.  The 0x03 is the number of bytes following in the buffer, which includes the F/A mask byte.   There are only 2 data bytes.  See section 4.3 of the protocol.

[pconroy]

Ahhhhhhhhhh.
I missed that.
Thank you!