Tianji Wu
HW2 implemented by interrupts
main.cpp@0:64a910e4a0d5, 2010-12-01 (annotated)
- Committer:
- the729
- Date:
- Wed Dec 01 02:48:22 2010 +0000
- Revision:
- 0:64a910e4a0d5
Who changed what in which revision?
| User | Revision | Line number | New contents of line |
|---|---|---|---|
| the729 | 0:64a910e4a0d5 | 1 | #include "mbed.h" |
| the729 | 0:64a910e4a0d5 | 2 | |
| the729 | 0:64a910e4a0d5 | 3 | //DigitalOut led1(LED1); |
| the729 | 0:64a910e4a0d5 | 4 | //DigitalOut led2(LED2); |
| the729 | 0:64a910e4a0d5 | 5 | |
| the729 | 0:64a910e4a0d5 | 6 | Serial pc(USBTX, USBRX); |
| the729 | 0:64a910e4a0d5 | 7 | |
| the729 | 0:64a910e4a0d5 | 8 | #define BTN0 p15 |
| the729 | 0:64a910e4a0d5 | 9 | #define BTN1 p20 |
| the729 | 0:64a910e4a0d5 | 10 | #define MAX_LENGTH 32 |
| the729 | 0:64a910e4a0d5 | 11 | |
| the729 | 0:64a910e4a0d5 | 12 | typedef unsigned int uint32_t; |
| the729 | 0:64a910e4a0d5 | 13 | typedef unsigned char uint8_t; |
| the729 | 0:64a910e4a0d5 | 14 | |
| the729 | 0:64a910e4a0d5 | 15 | enum { |
| the729 | 0:64a910e4a0d5 | 16 | IDLE=0, |
| the729 | 0:64a910e4a0d5 | 17 | HOST_INPUT, |
| the729 | 0:64a910e4a0d5 | 18 | USER_INPUT |
| the729 | 0:64a910e4a0d5 | 19 | } state; |
| the729 | 0:64a910e4a0d5 | 20 | uint32_t data = 0; |
| the729 | 0:64a910e4a0d5 | 21 | uint8_t datalength = 0; |
| the729 | 0:64a910e4a0d5 | 22 | |
| the729 | 0:64a910e4a0d5 | 23 | void precharge(PinName p) |
| the729 | 0:64a910e4a0d5 | 24 | { |
| the729 | 0:64a910e4a0d5 | 25 | DigitalIn prec(p); |
| the729 | 0:64a910e4a0d5 | 26 | prec.mode(PullUp); |
| the729 | 0:64a910e4a0d5 | 27 | prec.mode(PullNone); |
| the729 | 0:64a910e4a0d5 | 28 | } |
| the729 | 0:64a910e4a0d5 | 29 | |
| the729 | 0:64a910e4a0d5 | 30 | uint8_t read_cap() |
| the729 | 0:64a910e4a0d5 | 31 | { |
| the729 | 0:64a910e4a0d5 | 32 | precharge(BTN0); |
| the729 | 0:64a910e4a0d5 | 33 | precharge(BTN1); |
| the729 | 0:64a910e4a0d5 | 34 | wait_ms(5); |
| the729 | 0:64a910e4a0d5 | 35 | float s0 = AnalogIn(BTN0); |
| the729 | 0:64a910e4a0d5 | 36 | float s1 = AnalogIn(BTN1); |
| the729 | 0:64a910e4a0d5 | 37 | return ((s0>0.5)?0:1) + ((s1>0.5)?0:2); |
| the729 | 0:64a910e4a0d5 | 38 | } |
| the729 | 0:64a910e4a0d5 | 39 | |
| the729 | 0:64a910e4a0d5 | 40 | void block_output(const char * str) |
| the729 | 0:64a910e4a0d5 | 41 | { |
| the729 | 0:64a910e4a0d5 | 42 | pc.printf("%s", str); |
| the729 | 0:64a910e4a0d5 | 43 | } |
| the729 | 0:64a910e4a0d5 | 44 | |
| the729 | 0:64a910e4a0d5 | 45 | void uart_event() |
| the729 | 0:64a910e4a0d5 | 46 | { |
| the729 | 0:64a910e4a0d5 | 47 | uint8_t c; |
| the729 | 0:64a910e4a0d5 | 48 | if (state == IDLE) { |
| the729 | 0:64a910e4a0d5 | 49 | pc.putc(c = pc.getc()); |
| the729 | 0:64a910e4a0d5 | 50 | if (c == 'S') { |
| the729 | 0:64a910e4a0d5 | 51 | datalength = 0; |
| the729 | 0:64a910e4a0d5 | 52 | state = HOST_INPUT; |
| the729 | 0:64a910e4a0d5 | 53 | } else { |
| the729 | 0:64a910e4a0d5 | 54 | block_output("HOST ERROR. You are supposed to input S. Try again. \r\n"); |
| the729 | 0:64a910e4a0d5 | 55 | } |
| the729 | 0:64a910e4a0d5 | 56 | }else if (state == HOST_INPUT) { |
| the729 | 0:64a910e4a0d5 | 57 | pc.putc(c = pc.getc()); |
| the729 | 0:64a910e4a0d5 | 58 | if (c == '0' || c == '1') { |
| the729 | 0:64a910e4a0d5 | 59 | datalength ++; |
| the729 | 0:64a910e4a0d5 | 60 | if (datalength > MAX_LENGTH) { |
| the729 | 0:64a910e4a0d5 | 61 | block_output("\r\nLength execeeds maximum. \r\n"); |
| the729 | 0:64a910e4a0d5 | 62 | } else { |
| the729 | 0:64a910e4a0d5 | 63 | data = (data << 1) | (c-'0'); |
| the729 | 0:64a910e4a0d5 | 64 | } |
| the729 | 0:64a910e4a0d5 | 65 | } else if (c == 'E') { |
| the729 | 0:64a910e4a0d5 | 66 | block_output("\r\nInput End. Tap the caps now. \r\n"); |
| the729 | 0:64a910e4a0d5 | 67 | if (!datalength) { |
| the729 | 0:64a910e4a0d5 | 68 | block_output("Zero length. Try again. \r\n"); |
| the729 | 0:64a910e4a0d5 | 69 | state = IDLE; |
| the729 | 0:64a910e4a0d5 | 70 | } else { |
| the729 | 0:64a910e4a0d5 | 71 | data <<= (32-datalength); |
| the729 | 0:64a910e4a0d5 | 72 | state = USER_INPUT; |
| the729 | 0:64a910e4a0d5 | 73 | } |
| the729 | 0:64a910e4a0d5 | 74 | } else { |
| the729 | 0:64a910e4a0d5 | 75 | block_output("\r\nHOST ERROR. Continue input.\r\n"); |
| the729 | 0:64a910e4a0d5 | 76 | } |
| the729 | 0:64a910e4a0d5 | 77 | } |
| the729 | 0:64a910e4a0d5 | 78 | } |
| the729 | 0:64a910e4a0d5 | 79 | |
| the729 | 0:64a910e4a0d5 | 80 | void key_event(uint8_t c) |
| the729 | 0:64a910e4a0d5 | 81 | { |
| the729 | 0:64a910e4a0d5 | 82 | if (state != USER_INPUT) return; |
| the729 | 0:64a910e4a0d5 | 83 | if (c >= 3) block_output("TOUCH ERROR\n"); |
| the729 | 0:64a910e4a0d5 | 84 | c -= 1; |
| the729 | 0:64a910e4a0d5 | 85 | pc.putc(c + '0'); |
| the729 | 0:64a910e4a0d5 | 86 | if (c == (data >> 31)) { |
| the729 | 0:64a910e4a0d5 | 87 | datalength--; |
| the729 | 0:64a910e4a0d5 | 88 | if (!datalength) { |
| the729 | 0:64a910e4a0d5 | 89 | pc.printf("\r\nMATCH! \r\n"); |
| the729 | 0:64a910e4a0d5 | 90 | state = IDLE; |
| the729 | 0:64a910e4a0d5 | 91 | } |
| the729 | 0:64a910e4a0d5 | 92 | data <<= 1; |
| the729 | 0:64a910e4a0d5 | 93 | } else { |
| the729 | 0:64a910e4a0d5 | 94 | block_output("\r\nTOUCH ERROR. Continue touching.\r\n"); |
| the729 | 0:64a910e4a0d5 | 95 | } |
| the729 | 0:64a910e4a0d5 | 96 | } |
| the729 | 0:64a910e4a0d5 | 97 | |
| the729 | 0:64a910e4a0d5 | 98 | int main() { |
| the729 | 0:64a910e4a0d5 | 99 | uint8_t c; |
| the729 | 0:64a910e4a0d5 | 100 | state = IDLE; |
| the729 | 0:64a910e4a0d5 | 101 | pc.attach(&uart_event, Serial::RxIrq); |
| the729 | 0:64a910e4a0d5 | 102 | while(1) { |
| the729 | 0:64a910e4a0d5 | 103 | c = read_cap(); |
| the729 | 0:64a910e4a0d5 | 104 | if (!c) continue; |
| the729 | 0:64a910e4a0d5 | 105 | wait_ms(10); |
| the729 | 0:64a910e4a0d5 | 106 | if (c == read_cap()) { |
| the729 | 0:64a910e4a0d5 | 107 | while(read_cap()); |
| the729 | 0:64a910e4a0d5 | 108 | key_event(c); |
| the729 | 0:64a910e4a0d5 | 109 | } |
| the729 | 0:64a910e4a0d5 | 110 | } |
| the729 | 0:64a910e4a0d5 | 111 | } |