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View Full Version : Request in the middle of ACK_TIMER


endoftheworld
July 11th, 2006, 11:57 PM
Hey all,

Since the spec doesn't cover this in detail, I just wanted to know how what should be the outcome of this possible scenario :-

Controller sends SET_CMD (LAMP_STRIKE)
Responder sends back an ACK_TIMER ( wait 5 secs)
. .
. Controller sends a GET_CMD (any PID)
. Responder sends back an ACK_TIMR (wait 2 secs)
. .
. .
(end of 5 sec) Controller sends GET_QUEUED
what happens now ?
(In the Message Queue on Responder , we'll have 2 messages, which gets sent first ?)
I'd assume a FIFO (is that correct ?)

Hope it makes Sense

Cheers
EOD

sblair
July 13th, 2006, 10:53 PM
EOD,

It's up to the device. There are no requirements as to which message gets sent first. There could also be other messages pending as well, for example someone could have changed the DMX Start Address on the menu of the device so it Queued up a message to report that back to the console as well.

Put another way, the controller should never make an assumption that just because it got an ACK_TIMER earlier that when it does the next GET QUEUED_MESSAGE that it would get a response back for a specific PID.

Hope that helps..