11
keypad.cpp@16:a9feaa7ac039, 2012-11-08 (annotated)
- Committer:
- gj_schoneveld
- Date:
- Thu Nov 08 19:04:08 2012 +0000
- Revision:
- 16:a9feaa7ac039
- Parent:
- 15:873a9a452ef1
Updated Debounce
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
yoonghm | 0:2df66331c109 | 1 | #include "keypad.h" |
yoonghm | 0:2df66331c109 | 2 | |
yoonghm | 0:2df66331c109 | 3 | Keypad::Keypad(PinName row3, PinName row2, PinName row1, PinName row0, |
yoonghm | 0:2df66331c109 | 4 | PinName col3, PinName col2, PinName col1, PinName col0, |
yoonghm | 0:2df66331c109 | 5 | int debounce_ms): |
gj_schoneveld | 10:9a9ec143840b | 6 | _row0(row0), _row1(row1), _row2(row2), _row3(row3), |
gj_schoneveld | 10:9a9ec143840b | 7 | _cols(col0, col1, col2, col3) |
gj_schoneveld | 10:9a9ec143840b | 8 | { |
gj_schoneveld | 12:e6623f165199 | 9 | _debounce = debounce_ms; |
gj_schoneveld | 11:a45e64141ce6 | 10 | _rows[0] = &_row0; |
gj_schoneveld | 11:a45e64141ce6 | 11 | _rows[1] = &_row1; |
gj_schoneveld | 11:a45e64141ce6 | 12 | _rows[2] = &_row2; |
gj_schoneveld | 11:a45e64141ce6 | 13 | _rows[3] = &_row3; |
gj_schoneveld | 12:e6623f165199 | 14 | for (int r = 0; r < row_count; r++) |
gj_schoneveld | 12:e6623f165199 | 15 | _rows[r]->mode(PullUp); |
gj_schoneveld | 10:9a9ec143840b | 16 | _cols.mode(OpenDrain); |
gj_schoneveld | 10:9a9ec143840b | 17 | _cols.output(); |
gj_schoneveld | 11:a45e64141ce6 | 18 | } |
gj_schoneveld | 11:a45e64141ce6 | 19 | |
gj_schoneveld | 11:a45e64141ce6 | 20 | void Keypad::_setupFallTrigger(void) |
gj_schoneveld | 11:a45e64141ce6 | 21 | { |
gj_schoneveld | 12:e6623f165199 | 22 | for (int r = 0; r < row_count; r++) |
gj_schoneveld | 12:e6623f165199 | 23 | _rows[r]->fall(this, &Keypad::_callback); |
yoonghm | 0:2df66331c109 | 24 | } |
yoonghm | 0:2df66331c109 | 25 | |
gj_schoneveld | 10:9a9ec143840b | 26 | void Keypad::Start(void) |
gj_schoneveld | 10:9a9ec143840b | 27 | { |
gj_schoneveld | 11:a45e64141ce6 | 28 | /* make the columns zero so they can pull rows down */ |
yoonghm | 0:2df66331c109 | 29 | _cols = 0x00; |
yoonghm | 0:2df66331c109 | 30 | } |
yoonghm | 0:2df66331c109 | 31 | |
gj_schoneveld | 10:9a9ec143840b | 32 | void Keypad::Stop(void) |
gj_schoneveld | 10:9a9ec143840b | 33 | { |
gj_schoneveld | 11:a45e64141ce6 | 34 | /* make the columns one so they cannot pull any rows down anymore */ |
gj_schoneveld | 11:a45e64141ce6 | 35 | _cols = ~0x00; |
gj_schoneveld | 10:9a9ec143840b | 36 | } |
gj_schoneveld | 10:9a9ec143840b | 37 | |
gj_schoneveld | 10:9a9ec143840b | 38 | void Keypad::CallAfterInput(uint32_t (*fptr)(uint32_t index)) |
gj_schoneveld | 10:9a9ec143840b | 39 | { |
yoonghm | 0:2df66331c109 | 40 | _input.attach(fptr); |
gj_schoneveld | 11:a45e64141ce6 | 41 | _setupFallTrigger(); |
gj_schoneveld | 11:a45e64141ce6 | 42 | } |
gj_schoneveld | 11:a45e64141ce6 | 43 | |
gj_schoneveld | 11:a45e64141ce6 | 44 | int Keypad::DebouncedScan() |
gj_schoneveld | 11:a45e64141ce6 | 45 | { |
gj_schoneveld | 12:e6623f165199 | 46 | /* debounce */ |
gj_schoneveld | 11:a45e64141ce6 | 47 | wait_ms(_debounce); |
gj_schoneveld | 16:a9feaa7ac039 | 48 | |
gj_schoneveld | 16:a9feaa7ac039 | 49 | return Scan(); |
yoonghm | 0:2df66331c109 | 50 | } |
yoonghm | 0:2df66331c109 | 51 | |
gj_schoneveld | 11:a45e64141ce6 | 52 | int Keypad::Scan() |
gj_schoneveld | 10:9a9ec143840b | 53 | { |
gj_schoneveld | 11:a45e64141ce6 | 54 | /* lookup row */ |
gj_schoneveld | 11:a45e64141ce6 | 55 | int r = -1; |
gj_schoneveld | 11:a45e64141ce6 | 56 | for (r = 0; r < row_count; r++) { |
gj_schoneveld | 11:a45e64141ce6 | 57 | if (*_rows[r] == 0) |
gj_schoneveld | 11:a45e64141ce6 | 58 | break; |
gj_schoneveld | 11:a45e64141ce6 | 59 | } |
yoonghm | 0:2df66331c109 | 60 | |
gj_schoneveld | 11:a45e64141ce6 | 61 | /* if we didn't find a valid row, return */ |
gj_schoneveld | 11:a45e64141ce6 | 62 | if (!(0 <= r && r < row_count)) |
gj_schoneveld | 11:a45e64141ce6 | 63 | return -1; |
gj_schoneveld | 11:a45e64141ce6 | 64 | |
gj_schoneveld | 16:a9feaa7ac039 | 65 | /* scan columns to find out which one pulls down the row */ |
yoonghm | 0:2df66331c109 | 66 | int c = -1; |
gj_schoneveld | 11:a45e64141ce6 | 67 | for (c = 0; c < col_count; c++) { |
gj_schoneveld | 11:a45e64141ce6 | 68 | _cols = ~(1 << c); |
gj_schoneveld | 11:a45e64141ce6 | 69 | if (*_rows[r] == 0) |
gj_schoneveld | 11:a45e64141ce6 | 70 | break; |
yoonghm | 0:2df66331c109 | 71 | } |
gj_schoneveld | 11:a45e64141ce6 | 72 | |
gj_schoneveld | 11:a45e64141ce6 | 73 | /* re-energize all columns */ |
gj_schoneveld | 11:a45e64141ce6 | 74 | Start(); |
gj_schoneveld | 11:a45e64141ce6 | 75 | |
gj_schoneveld | 11:a45e64141ce6 | 76 | /* if we didn't find a valid column, return */ |
gj_schoneveld | 11:a45e64141ce6 | 77 | if (!(0 <= c && c < col_count)) |
gj_schoneveld | 11:a45e64141ce6 | 78 | return -1; |
gj_schoneveld | 11:a45e64141ce6 | 79 | |
gj_schoneveld | 11:a45e64141ce6 | 80 | return r * col_count + c; |
yoonghm | 0:2df66331c109 | 81 | } |
gj_schoneveld | 16:a9feaa7ac039 | 82 | |
gj_schoneveld | 13:fb6929fac0db | 83 | int Keypad::DebouncedScanMultiple() |
gj_schoneveld | 13:fb6929fac0db | 84 | { |
gj_schoneveld | 13:fb6929fac0db | 85 | /* debounce */ |
gj_schoneveld | 13:fb6929fac0db | 86 | wait_ms(_debounce); |
gj_schoneveld | 16:a9feaa7ac039 | 87 | |
gj_schoneveld | 16:a9feaa7ac039 | 88 | return ScanMultiple(); |
gj_schoneveld | 13:fb6929fac0db | 89 | } |
gj_schoneveld | 13:fb6929fac0db | 90 | |
gj_schoneveld | 13:fb6929fac0db | 91 | int Keypad::ScanMultiple() |
gj_schoneveld | 13:fb6929fac0db | 92 | { |
gj_schoneveld | 16:a9feaa7ac039 | 93 | int res = 0; |
gj_schoneveld | 13:fb6929fac0db | 94 | for (int c = 0; c < col_count; c++) { |
gj_schoneveld | 13:fb6929fac0db | 95 | _cols = ~(1 << c); |
gj_schoneveld | 13:fb6929fac0db | 96 | for (int r = 0; r < row_count; r++) { |
gj_schoneveld | 13:fb6929fac0db | 97 | if (*_rows[r] == 0) { |
gj_schoneveld | 13:fb6929fac0db | 98 | res |= 1 << (r * col_count + c); |
gj_schoneveld | 13:fb6929fac0db | 99 | } |
gj_schoneveld | 13:fb6929fac0db | 100 | } |
gj_schoneveld | 13:fb6929fac0db | 101 | } |
gj_schoneveld | 16:a9feaa7ac039 | 102 | |
gj_schoneveld | 13:fb6929fac0db | 103 | return res; |
gj_schoneveld | 13:fb6929fac0db | 104 | } |
yoonghm | 0:2df66331c109 | 105 | |
gj_schoneveld | 11:a45e64141ce6 | 106 | void Keypad::_callback() |
gj_schoneveld | 10:9a9ec143840b | 107 | { |
gj_schoneveld | 11:a45e64141ce6 | 108 | /* lookup */ |
gj_schoneveld | 11:a45e64141ce6 | 109 | int position = DebouncedScan(); |
gj_schoneveld | 16:a9feaa7ac039 | 110 | |
gj_schoneveld | 11:a45e64141ce6 | 111 | /* call back a valid position */ |
gj_schoneveld | 11:a45e64141ce6 | 112 | if (position >= 0) |
gj_schoneveld | 11:a45e64141ce6 | 113 | _input.call(position); |
yoonghm | 0:2df66331c109 | 114 | } |
gj_schoneveld | 14:f6c3647bf421 | 115 |