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DVD Player Control Logic

SensivaSensiva Posts: 211
in AMX General Discussion
Hi all..

I am doing practical for Programmer Certificate, and now i am stuck with the control logic of the DVD Player, actually i am not that much familiar with standalone players, so here is logic assumptions that I built on my own. :o

- STOP will be ON if there is a media inserted and no transport actions
(no media --> STOP is OFF)
- Transports are disabled while in MENU
- changing discs will stop (STOP is ON) and exit MENU
- Pausing while playing -- PLAY will remain ON
- PLAY & PAUSE will exit SEARCH
- SEARCH is latching command
- searching will turn PLAY ON
- searching while paused will exit PAUSE
- PLAY will turn OFF both PAUSE and SEARCH
- MENU command pauses playback
- SELECT will start playback
- skipping will not turn OFF STOP
- skipping will start playback only if the player was playing back OR PAUSED
(turning off pause as well)
- skipping will exit SEARCH

I am not asking for code, I want only someone to validate this logic specially the latching searching buttons, i don't want AMX University's Cops get me out of the track :eek:

Comments

  • NMarkRobertsNMarkRoberts Posts: 455
    The complexity of the rules you have laid out and the assumptions you have to blindly make only demonstrate that it's best not to even try to guess what a DVD is doing when you are controlling it without feedback. If you have state feedback, you don't need all those rules; if you don't have state feedback, you can never be sure what it is doing.
  • SensivaSensiva Posts: 211
    Feedback
    NMarkRoberts wrote:
    If you have state feedback, you don't need all those rules; if you don't have state feedback, you can never be sure what it is doing.

    This is a RS232 DVDPlayer, and it has only two major responses
    - Media Type in the drive.
    - valid or invalid command acknowledgment
  • mpullinmpullin Posts: 949
    NMarkRoberts wrote:
    The complexity of the rules you have laid out and the assumptions you have to blindly make only demonstrate that it's best not to even try to guess what a DVD is doing when you are controlling it without feedback. If you have state feedback, you don't need all those rules; if you don't have state feedback, you can never be sure what it is doing.
    Brilliant answer, I should have used that on my test :p
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