The ISR for the external interrupt
| 60 | |
| 61 | // The ISR for the external interrupt |
| 62 | void ps2interrupt(void) |
| 63 | { |
| 64 | static uint8_t bitcount=0; |
| 65 | static uint8_t incoming=0; |
| 66 | static uint32_t prev_ms=0; |
| 67 | uint32_t now_ms; |
| 68 | uint8_t n, val; |
| 69 | |
| 70 | val = digitalRead(DataPin); |
| 71 | now_ms = millis(); |
| 72 | if (now_ms - prev_ms > 250) { |
| 73 | bitcount = 0; |
| 74 | incoming = 0; |
| 75 | } |
| 76 | prev_ms = now_ms; |
| 77 | n = bitcount - 1; |
| 78 | if (n <= 7) { |
| 79 | incoming |= (val << n); |
| 80 | } |
| 81 | bitcount++; |
| 82 | if (bitcount == 11) { |
| 83 | uint8_t i = head + 1; |
| 84 | if (i >= BUFFER_SIZE) i = 0; |
| 85 | if (i != tail) { |
| 86 | buffer[i] = incoming; |
| 87 | head = i; |
| 88 | } |
| 89 | bitcount = 0; |
| 90 | incoming = 0; |
| 91 | } |
| 92 | } |
| 93 | |
| 94 | static inline uint8_t get_scan_code(void) |
| 95 | { |
nothing calls this directly
no outgoing calls
no test coverage detected