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8051 "data" storage within program memory - how?

Discussion in '8051/8951' started by L0D|Mr_B, Jan 11, 2004.

  1. L0D|Mr_B

    L0D|Mr_B New Member

    Joined:
    Oct 15, 2003
    Messages:
    13
    Likes:
    0
    Location:
    Coventry, UK
    hi all.

    i'm redesigning my project for an "advanced" fan controller, using the 8051, and ive run into a brick wall :shock:

    what i want to do is store commands in memory for a VFD (hard stored - not changeable, these are the commands to be passed to the VFD by my routines, it's for grfx, etc). what i want to do is something like :-

    e.g.

    LABEL data "this text is to be printed on the VFD"

    e.g

    DRAWBOX data 04,88,7F,90,94,00

    .... where all the data is hex codes - a string - these would be predetermined commands for the VFD. question is, how do i access this data string, when i think the 8051 can only access DATA memory for data manipulation, not access program memory, where obviously this code sting for the VFD would reside.

    i was going to add the strings in memory, then access them with a routine which would move along the string till it hit's a 00, where by the subroutine returns. my project was going to be PIC based, till i hit this, so going to 8051, plus i need more memory space (now can have 64K)

    i know i could write something like :-

    send "04"
    send "88"
    send "7f"
    send .......

    ... but this would be both very wastefull and time consuming to code. i guess it comes down to "how do i load a register with a byte from program memory"

    any ideas? can u think of another microcontroller which can be programmed via external eprom which has this facility, if it cant be done on the 8051?

    B
     
  2. L0D|Mr_B

    L0D|Mr_B New Member

    Joined:
    Oct 15, 2003
    Messages:
    13
    Likes:
    0
    Location:
    Coventry, UK
    ok, figured it. didnt spot the command MOVC

    sorry for being dumb !!!!

    B
     

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