Fork without short circuits
Fork of keypad by
No extra hardware is needed besides the wires and switches. The columns are outputs configured with open drain. The rows are inputs configured with pull up resistors. A key press pulls down its row. With scanning the column is determined thereafter.
See SaveKeypad for an example usage.
Diff: keypad.cpp
- Revision:
- 12:e6623f165199
- Parent:
- 11:a45e64141ce6
- Child:
- 13:fb6929fac0db
diff -r a45e64141ce6 -r e6623f165199 keypad.cpp --- a/keypad.cpp Sat Nov 03 23:33:52 2012 +0000 +++ b/keypad.cpp Sat Nov 03 23:43:46 2012 +0000 @@ -6,25 +6,21 @@ _row0(row0), _row1(row1), _row2(row2), _row3(row3), _cols(col0, col1, col2, col3) { + _debounce = debounce_ms; _rows[0] = &_row0; _rows[1] = &_row1; _rows[2] = &_row2; _rows[3] = &_row3; - _debounce = debounce_ms; - _row0.mode(PullUp); - _row1.mode(PullUp); - _row2.mode(PullUp); - _row3.mode(PullUp); + for (int r = 0; r < row_count; r++) + _rows[r]->mode(PullUp); _cols.mode(OpenDrain); _cols.output(); } void Keypad::_setupFallTrigger(void) { - _row0.fall(this, &Keypad::_callback); - _row1.fall(this, &Keypad::_callback); - _row2.fall(this, &Keypad::_callback); - _row3.fall(this, &Keypad::_callback); + for (int r = 0; r < row_count; r++) + _rows[r]->fall(this, &Keypad::_callback); } void Keypad::Start(void) @@ -47,9 +43,9 @@ int Keypad::DebouncedScan() { + /* debounce */ int key1 = Scan(); - /* debounce */ wait_ms(_debounce); int key2 = Scan(); @@ -100,4 +96,3 @@ if (position >= 0) _input.call(position); } -