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EEPROM and the SX — Parallax Forums

EEPROM and the SX

david43085david43085 Posts: 8
edited 2009-01-04 02:19 in General Discussion
The Stamp uses EEPROM for memory and it is integrated directly onto the stamp.· How does the SX accomplish this same feat?· I am trying to understand the required (basic)·components of microcontroller circuits and and how they interact with each other.· Recommended reading?

Thanks

Dave

Comments

  • BeanBean Posts: 8,129
    edited 2009-01-02 02:56
    Dave,
    · The SX contains flash memory that stores the program. This memory is not changable by the SX itself, only the programmer can change it.

    · The stamp has a SX (or PIC) that runs a program from it's flash memory. That program reads the basic program from the eeprom and executes it.

    Bean.

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    ·The next time you need a hero don't look up in the sky...Look in the mirror.


    ·
  • david43085david43085 Posts: 8
    edited 2009-01-02 04:39
    So that is the purpose of the SX Key, taking the place of the eeprom for providing the program into the chips memory?

    Thanks

    Dave
  • InSilicoInSilico Posts: 52
    edited 2009-01-04 02:19
    The SX contains an internal flash EEPROM that contains the actual program. To load it, you need something called a programmer.

    The SX-Key is this programmer for SX chips. The SX-Key contains another SX (look on the SX-Key carefully, it might be labeled "Ubicom" but it's the same thing) that puts the target SX into a special mode that allows it to load the SX's internal EEPROM with the actual assembly.

    This functionality is all built into the silicon of the SX (and all microcontrollers in general).

    The Basic Stamp all have a microcontroller as well (some even have the SX), but the program on those chips·is fixed and preprogrammed in a factory. The actual Basic Stamp program that you write up is stored on an external EEPROM, and the fixed built-in program in the microcontroller reads off the program in the external EEPROM and performs those actions. This process is called "interpreting".

    The program that you load in SXes·is not interpreted.·The program is read from its internal EEPROM and is executed directly by the circuitry of the silicon. The program that you load in Basic Stamps, however, is read from an external EEPROM and is executed by another program.

    Recommended reading includes the SX-Tech manual and Gunther Daubach's Programming the SX Microcontroller.

    Post Edited (InSilico) : 1/4/2009 2:30:39 AM GMT
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