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JHD12864E graphics lcd interfacing with LPC2148

hi i m trying to interface a graphics lcd jhd12864e with LPC2148 having arm7 core..i was able to interface it with 89v51rd2 successfully but it does not work with arm..can any one provide some consultancy regarding this..also if any one has worked using the same lcd please give me tour email id for contact..

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  • Timing has been suggested to you more than once as a likely problem. Single-stepping tells you nothing about your timing!

    "during simulation ... checked the peripherals it was doing the desired operation"

    But was that the correct operation?

    "jhd12864e does not have much documentation and examples on interfacing with arm"

    The LCD controller neither knows nor cares what processor you use.

    It is up to you to read the controller's specification, and implement its requirements.

    Again, you say you have a working 8051 implementation - so have you done a detailed comparison of the signals for your two implementations?

    You need to get your oscilloscope out, and look at the actual signals on the wires...

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  • Timing has been suggested to you more than once as a likely problem. Single-stepping tells you nothing about your timing!

    "during simulation ... checked the peripherals it was doing the desired operation"

    But was that the correct operation?

    "jhd12864e does not have much documentation and examples on interfacing with arm"

    The LCD controller neither knows nor cares what processor you use.

    It is up to you to read the controller's specification, and implement its requirements.

    Again, you say you have a working 8051 implementation - so have you done a detailed comparison of the signals for your two implementations?

    You need to get your oscilloscope out, and look at the actual signals on the wires...

Children
  • Timing has been suggested to you more than once as a likely problem. Single-stepping tells you nothing about your timing!
    it seems you think "NAAH, I know better"

    now a few comments on Andys reply
    But was that the correct operation?</
    ALSO but was it correctly simulated (I/O simulation is very error prone)
    ALSO simulation does NOT not at all consider timing.

    also;
    jhd12864e does not have much documentation and examples on interfacing with arm
    and so friggin what. The required signals are documented, what more do you need? a fried pigeon flying in through the window?

    I suggest you refrain from posting till you have had the scope out and checked the timings against the datasheet

    Erik

  • It has also been pointed out that "working" does not necessarily mean that it is a "good" or "correct" implementation - it could well be flawed, but in a way (or ways) that just happens not to show-up in your 8051 system.

    For a classic example, see: www.8052.com/.../178415

    So, not only do you need to get your scope on the new ARM implementation - to see why it doesn't work - but you also need to get your scope on the old 8051 implementation - to check how well it really is working...!