PMP Mail Archive: Re: PMP> Definitions of Active, Busy, Idle, Standby

Re: PMP> Definitions of Active, Busy, Idle, Standby

Lloyd Young (lpyoung@lexmark.com)
15 Mar 97 8:52:37 EST

In coming up with the new definitions that were proposed, I consulted
with several people and went through different scenarios in a printer
and various subunits (input features, output features, interfaces,
markers, etc.) to try to determine generic definitions that would
apply to various situations. While the definition that Bill and
Chuck stated below appeared to work good for interfaces, it seemed
to lack something when applied to other subunits.

For example, we considered a large capacity input feature that has
an elevator to raise and lower the paper. Before opening the
door to replenish the paper supply, an operator pushes a button
to lower the elevator. We considered the paper input to be
"busy" while lowering the elevator. The next state after "busy"
would be "idle" (if the door was not open) or "offline" (if the
door was open) or even "down" (if the elevator jammed while lowering).

Another example was an inkjet printer. Occasionally an inkjet printer
must move the inkjet heads over to a cleaning station. We would consider
the marker to be "busy" while the cleaning cycle is going on. After the
cleaning cycle is finished, the next state could be "active", "idle"
(depending on what was going on before and during the cleaning cycle)
or "down" (if a problem was detected while cleaning).

This are two examples of why we decided not to include any next state
transitions in our new definition.

----- Included new definition of "busy" for reference purposes only -----

Busy: the printer or subunit is performing a function (not necessarily
it's primary function) and is not immediately available for it's
primary function.
-------------------- Original message -------------------------
To: pmp%pwg.org @ interlock.lexmark.com @ SMTP
cc: (bcc: Lloyd Young)
From: adamsc%pogo.WV.TEK.COM @ interlock.lexmark.com (Chuck Adams) @ SMTP
Date: 03/13/97 05:11:26 PM
Subject: Re: PMP> Definitions of Active, Busy, Idle, Standby

> Busy - The printer or subunit is "Active" and has also reached a
> resource threshold whereby it will not accept any new print jobs for a
> finite period of time. The expected next state transition from the
> "busy" state is to the "active" state, implying that resources are
> again available to accept new print jobs.

I like Bill's suggestion with one minor change.

The expected next state transition from the "busy" state is to the
"active" or "available" state,
implying that resources are again available to accept new print jobs.

Chuck Adams