JP1 Remotes

So my earlier post is wrong, and you should pay attention to what Barf wrote. From my (revised) point of view -16::0 is valid syntax, but it does not have a usefully defined value.

Ok. Thanks. It would be good to have the specification speak to this case. It could say that implementation ...

First, note that the IRP spec has an error: it uses 2's complement rather than 1's complement . However, the accompanying text makes that clear.

ROTFL Well, I had a set of follow up questions about that which are now unnecessary.

Certainly 1s complement has made for a much more interesting ...

See the end of section 5.3: Note that the "-" prefix is not permitted unless b is present. So -16::0 is not a legal construct. As you can probably tell, I'm a newbie at IRP. Please excuse my questions that miss the mark. What I had meant to write was:

<-1,1|1,-1>((-16)::0)
I think this is valid ...

In http://www.hifi-remote.com/wiki/index.php?title=IRP_Notation#Data_Structures
A bitfield evaluates to a binary form, an integer value expressed in binary notation with a fixed finite or infinite bit length in which negative integers are expressed in 1's complement notation.
The document says ...

3FG wrote:0 would mean zero bits.

Oh. Thanks. I had it backwards.

What about in expression contexts ?

For example: In this case, A=8. What is the expectation for the value of B ?

But I don't see a good reason to exclude b==0. Thanks for clarifying. Zero means variable number of bits.

I don't think I see that anywhere in the IRP Notation Specification.

This still leaves me with my other question regarding, it appears, either (-12)::0 or even 12::0. Since the width of the ...

The IRP Execution Model says:

ELSE IF irstream item IS bitfield THEN

EVALUATE bitfield AS binary form;
IF current bitspec IS NULL THEN

ERROR;

ELSE

PUSH binary form INTO buffer OF current bitspec;

END IF;


What is the correct interpretation for a bitfield with a negative value, for ...

I am working through an implementation of an IRP parser and following the details in http://www.hifi-remote.com/wiki/index.php?title=IRP_Notation#Semantics_4

I have a couple of questions. To begin:

If either b or c is negative then the bitfield is invalid. In the execution process, a bitfield is ...