main.cpp

00001 #include "mbed.h"
00002 #include "PinDetect.h"
00003 
00004 /*CS294 HW2 - Text Entry code. */
00005 
00006 Serial pc(USBTX, USBRX);
00007 
00008 PinDetect button1(D2);
00009 PinDetect button2(D3);
00010 PinDetect button3(D4);
00011 PinDetect button4(D5);
00012 PinDetect button5(D6);
00013 PinDetect button6(D7);
00014 PinDetect button7(D8);
00015 PinDetect button8(D9);
00016 PinDetect button9(D10);
00017 /*Reserved for Space bar*/
00018 PinDetect button10(D11);
00019 
00020 int state[10];
00021 
00022 int alphabet_map[] = {'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y','Z',' '};
00023 
00024 void button1_pressed() {
00025     state[0] = 1;
00026 }
00027 void button2_pressed() {
00028     state[1] = 1;
00029 }
00030 void button3_pressed() {
00031     state[2] = 1;
00032 }
00033 void button4_pressed() {
00034     state[3] = 1;
00035 }
00036 void button5_pressed() {
00037     state[4] = 1;
00038 }
00039 void button6_pressed() {
00040     state[5] = 1;
00041 }
00042 void button7_pressed() {
00043     state[6] = 1;
00044 }
00045 void button8_pressed() {
00046     state[7] = 1;
00047 }
00048 void button9_pressed() {
00049     state[8] = 1;
00050 }
00051 void button10_pressed() {
00052     state[9] = 1;
00053 }
00054 
00055 void button1_released() {
00056     state[0] = 0;
00057 }
00058 void button2_released() {
00059     state[1] = 0;
00060 }
00061 void button3_released() {
00062     state[2] = 0;
00063 }
00064 void button4_released() {
00065     state[3] = 0;
00066 }
00067 void button5_released() {
00068     state[4] = 0;
00069 }
00070 void button6_released() {
00071     state[5] = 0;
00072 }
00073 void button7_released() {
00074     state[6] = 0;
00075 }
00076 void button8_released() {
00077     state[7] = 0;
00078 }
00079 void button9_released() {
00080     state[8] = 0;
00081 }
00082 void button10_released() {
00083     state[9] = 0;
00084 }
00085 
00086 /* Function that performs Text-Entry algorithm.
00087 Input: Button state array.
00088 Output: Next character to display. */
00089 char get_next_char(int state[]) {
00090     char next_char;
00091     if (state[9]) {
00092         /*Space bar*/
00093         next_char = alphabet_map[26];
00094     } else if (state[0]) {
00095         /*A - H*/
00096         for (int j = 1; j < 9; j++) {
00097             if (state[j]) {
00098                 next_char = alphabet_map[j - 1];
00099                 break;
00100             }
00101         }
00102     } else if (state[1]) {
00103         /*I - O*/
00104         for (int j = 2; j < 9; j++) {
00105             if (state[j]) {
00106                 next_char = alphabet_map[j + 6];
00107                 break;
00108             }
00109         }       
00110     } else if (state[2]) {
00111         /*P - U*/
00112         for (int j = 3; j < 9; j++) {
00113             if (state[j]) {
00114                 next_char = alphabet_map[j + 12];
00115                 break;
00116             }
00117         }
00118     } else if (state[3]) {
00119         /*V - Z*/
00120         for (int j = 4; j < 9; j++) {
00121             if (state[j]) {
00122                 next_char = alphabet_map[j + 17];
00123                 break;
00124             }
00125         }
00126     } else {
00127         next_char = NULL;
00128     }
00129     return next_char;
00130 }
00131 
00132 int main() {
00133 
00134     /* Setup buttons. */
00135     button1.mode(PullDown);
00136     button2.mode(PullDown);
00137     button3.mode(PullDown);
00138     button4.mode(PullDown);
00139     button5.mode(PullDown);
00140     button6.mode(PullDown);
00141     button7.mode(PullDown);
00142     button8.mode(PullDown);
00143     button9.mode(PullDown);
00144     button10.mode(PullDown);
00145 
00146     /*Add callback functions for events when buttons are pressed. */
00147     button1.attach_asserted(&button1_pressed);
00148     button2.attach_asserted(&button2_pressed);
00149     button3.attach_asserted(&button3_pressed);
00150     button4.attach_asserted(&button4_pressed);
00151     button5.attach_asserted(&button5_pressed);
00152     button6.attach_asserted(&button6_pressed);
00153     button7.attach_asserted(&button7_pressed);
00154     button8.attach_asserted(&button8_pressed);
00155     button9.attach_asserted(&button9_pressed);
00156     button10.attach_asserted(&button10_pressed);
00157 
00158     /*Add callback functions for events when buttons are released. */
00159     button1.attach_deasserted(&button1_released);
00160     button2.attach_deasserted(&button2_released);
00161     button3.attach_deasserted(&button3_released);
00162     button4.attach_deasserted(&button4_released);
00163     button5.attach_deasserted(&button5_released);
00164     button6.attach_deasserted(&button6_released);
00165     button7.attach_deasserted(&button7_released);
00166     button8.attach_deasserted(&button8_released);
00167     button9.attach_deasserted(&button9_released);
00168     button10.attach_deasserted(&button10_released);
00169 
00170     button1.setAssertValue(0);
00171     button2.setAssertValue(0);
00172     button3.setAssertValue(0);
00173     button4.setAssertValue(0);
00174     button5.setAssertValue(0);
00175     button6.setAssertValue(0);
00176     button7.setAssertValue(0);
00177     button8.setAssertValue(0);
00178     button9.setAssertValue(0);
00179     button10.setAssertValue(0);
00180 
00181     button1.setSampleFrequency();
00182     button2.setSampleFrequency();
00183     button3.setSampleFrequency();
00184     button4.setSampleFrequency();
00185     button5.setSampleFrequency();
00186     button6.setSampleFrequency();
00187     button7.setSampleFrequency();
00188     button8.setSampleFrequency();
00189     button9.setSampleFrequency();
00190     button10.setSampleFrequency();
00191 
00192     char curr_char = NULL;
00193     char next_char;
00194 
00195     /*Loop forever. */
00196     while(1) {
00197         next_char = get_next_char(state);
00198         if (!next_char) {
00199             curr_char = next_char;
00200         }
00201 
00202         if (next_char != curr_char) {
00203                 pc.printf("%c", next_char);
00204                 curr_char = next_char;
00205         }
00206         wait(.2);
00207     }
00208 
00209 }