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Old January 20th, 2007   #5
Task Group Member
Join Date: Jun 2006
Posts: 181

The use of this PID is likely to be rather limited, as it currently cannot properly describe a very simple PID.

For example : we have added to our responders the ability to control the state of a POWERON_SELFTEST feature -a flag held in non-volatile storage and requiring user selection.

The GET: PID has no need for any data and so has a PDL=0x00

It retrieves the current state of the flag.

The SET: PID has a one byte argument 0 or 1 to act as the state selection, so the PDL is 0x01, and the allowed data is 0 or 1.

This is similar to many standard PIDs already featured in the standard.

Unfortunately the fields associated with the current PARAMATER_DESCRIPTION PID do not allow for different GET/SET PDL declarations.

In my view we should withdraw this PID and replace it with one that allows declaration of

(a) whether it supports GETs and SETs as per Table A-16
(b) the GET:PDL and GET: Data Type as per Table A-15
(c) the SET:PDL and SET: Data Type as per Table A-15
(d) and optional MAX GET and MAX SET Data value (32bit) to be used ONLY if declared data type is Byte/Word or DWord as per Table A-15
(e) an optional text string description.

Peter Willis
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