Self test description question

[ericthegeek]

> I use GET PARAMETER_DESCRIPTION PERFORM_SELFTEST
> to get the minimum and maximum valid values.

That's a clever solution, but I don't think it will be widely supported.

Technically, PARAMETER_DESCRIPTION is only valid for manufacturer specific PIDs. The "PID # Requested" fields has a range of 0x8000 to 0xFFDF per section 10.4.2.

[sjackman]

Hi Eric,

I agree, it's outside the spec. If the controller does request PARAMETER_DESCRIPTION, there's no harm done if the responder returns an error.

As a controller displaying a UI to the user, I've taken to requesting the max value (as above). If I get a response, I limit the UI to display only those tests, otherwise I display all 255.

Cheers,
Shaun

[hamish]

This issue is one that remains open and one I discussed at the thin end of the CPWG on Monday. Anyone who was at the last Plugfest may have witnessed the result of testing for 255 self tests, not a pretty sight.

I propose the addition of PID SUPPORTED_SELFTESTS, being a canned response. At the next revision of the standard, a minimum of "Should" be supported, although I personally would vote for "Shall" be supported, leaving controller developers responsible, as indeed they already are, for the case that that the PID has not been implemented.

Where do we go from here?