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bert botha of Kulkoni-ITS South Africa Says:

Hi Valerie,
Looking at your spec for the SIPO chip, this is eight bit out. I used the 74LS195AN which is four bit out.
You can modify the code for using a word instead of a nibble by changing the following lines:
Remove the label SERIAL1
Change MOVLW 0x04 to MOVLW 0x08
Delete all CALL SERIAL1 lines in the program
Otherwise, use the LS196AN and don't forget to wire the lower nibble of the LCD low.(Otherwise they will float and give false inputs)
If this does not help, contact me again.
Good luck!

Questions:

• bert botha of Kulkoni-ITS South Africa asks:

  Just struck me whats wrong! Are you using pull down resistors for scanning the 4rows?. If not then the 'open' TTL will float and be 'seen' as high, registering an input. The inputs are only pulled high by a keystroke.

  +

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