Undocumented Keypad Feature

2014-04-06
2014-04-07
  • Thomas Henry
    Thomas Henry
    2014-04-06

    To the keeper of the Help file:

    The keypad routine has a nice feature, not unlike what Kent added to the LCD routine this week. In particular, if using pull-up resistors on the columns, do nothing. But if using pull-down resistors, simply add this line to your program:

    #define KEYPAD_PULLDOWN
    

    and the scan logic will be inverted appropriately. This isn't mentioned in the Help file.

    To make the Help file even more helpful, you might want to mention that the pull-ups or pull-downs go on the columns only, and are typically 4.7k to 10k in value.

    Thomas Henry

     
  • Anobium
    Anobium
    2014-04-07

    Considered it added. :-)

    I will post later this week to the online Help, then, the CHM at the end of the month as I am adding more code this month.

    Added to May 2014 Help File.

     
    Last edit: Anobium 2014-05-16