main.cpp

00001 /* mbed Example Program
00002  * Copyright (c) 2006-2014 ARM Limited
00003  *
00004  * Licensed under the Apache License, Version 2.0 (the "License");
00005  * you may not use this file except in compliance with the License.
00006  * You may obtain a copy of the License at
00007  *
00008  *     http://www.apache.org/licenses/LICENSE-2.0
00009  *
00010  * Unless required by applicable law or agreed to in writing, software
00011  * distributed under the License is distributed on an "AS IS" BASIS,
00012  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00013  * See the License for the specific language governing permissions and
00014  * limitations under the License.
00015  */
00016 
00017 #include "mbed.h"
00018 
00019 BusIn nibble(D0, D1, D2, D3); // Change these pins to buttons on your board.
00020 
00021 int main() {
00022     
00023     // Optional: set mode as PullUp/PullDown/PullNone/OpenDrain
00024     nibble.mode(PullNone); 
00025     
00026     while(1) {
00027         // check bits set in nibble
00028         switch(nibble & nibble.mask()) { // read the bus and mask out bits not being used
00029             case 0x0: printf("0b0000, D3,D2,D1,D0 are low  \n\r");break;
00030             case 0x1: printf("0b0001,          D0  is high \n\r");break;
00031             case 0x2: printf("0b0010,       D1     is high \n\r");break; 
00032             case 0x3: printf("0b0011,       D1,D0 are high \n\r");break;
00033             case 0x4: printf("0b0100,    D2        is high \n\r");break;
00034             case 0x5: printf("0b0101,    D2,  ,D0 are high \n\r");break;
00035             case 0x6: printf("0b0110,    D2,D1    are high \n\r");break;
00036             case 0x7: printf("0b0111,    D2,D1,D0 are high \n\r");break;
00037             case 0x8: printf("0b1000, D3           is high \n\r");break; 
00038             // ...
00039             case 0xF: printf("0b1111, D3,D2,D1,D0 are high \n\r");break;
00040         }
00041         wait(1);
00042     }
00043 }