galaktor / microview_pins Goto Github PK

Newer Arduino supports INPUT_PULLUP mode, but older can use the AVR pullups via setting mode to INPUT and writing HIGH to the pin.

Old way

pinMode(1, INPUT);
digitalWrite(1, HIGH); // write, even if in INPUT mode; activates pullup

New way

pinMode(1, INPUT_PULLUP);

The type of resistor will depend on the AVR chip, check with the MicroView spec which resistors it has.

Reading values will have to be inverted to maintain current "fill == has value" logic; because using pullup will invert read values, i.e. it becomes active-low.

Seems like a useful thing to do by default.

• http://arduino.cc/en/Tutorial/AnalogInputPins
• http://arduino.cc/en/Tutorial/InputPullupSerial

50 millis was a random first start, but there's no reason why it can't be much smaller, say single digit millis.

by drawing the char in place of the box as black or white color, a "fill"-like effect can be achieved while improving readability by simplifying the interface

Only the pin states (=boxes) need updating inside "loop()". Text can all be drawn once inside "setup()".

When I removed a uView.Clear(PAGE) early on, I foolishly made it so that filled boxes are never emptied again. D'oh.