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Assigning parallel boolean data into a variable in BS2 (Keypad decoder (74C922N — Parallax Forums

Assigning parallel boolean data into a variable in BS2 (Keypad decoder (74C922N

CruxCrux Posts: 74
edited 2007-06-06 16:49 in BASIC Stamp
I am currently having a problem how i will store a parallel boolean data inside the BS2 in just one variable. I am interfacing a 74C922N keypad decoder w/ BS2 and d bus is taking up 4 pins from both chip.So its a nibble or a word data perhaps that i will use.Problem is I cant find how to gather all those paralleled bits and store it into my specified variable

Comments

  • Chris SavageChris Savage Parallax Engineering Posts: 14,406
    edited 2007-06-06 16:49
    Crux,

    Using the 4-bit parallel output of the 74C922N you can tie those lines to a 4-bit group on the BASIC Stamp such as INA (P0-P3), INB (P4-P7), etc. Then you can store that value directly into a NIB variable as soon as you detect the Data Available line going high. You'll need a 5th I/O pin outside the group to detect the DA line.· I hope this helps. Take care.

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    Chris Savage
    Parallax Tech Support
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