main.cpp

00001 /* MAX44000 Ambient Light Sensor / Proximity Sensor Demo
00002  * This demonstrates some of the capabilities of the MAX44000.
00003  * 
00004  * This is written to work with the ARD2PMD adapter board and 
00005  * the MAX44000PMB1.  It uses the standard Arduino pin names 
00006  * and it will compile for most arduino form-factor mbed boards.
00007  *
00008  * LED1 toggles when something is first detected by the proximity sensor.
00009  * LED2 indicates when the Ambient Light Sensor reads grater than alsLim.
00010  * LED3 will stay on whenever something is detected by the proximity sensor 
00011  *   and stay on for an additional 5s after it is no longer detected.
00012  *
00013  * The following boards have been tested to work:
00014  *   MAX32600MBED
00015  *   FRDM-KL25Z 
00016  *   FRDM-K64F
00017  *   Seeeduino Arch (LEDs inverted)
00018  *   Seeeduino Arch Pro
00019  *   ST Nucleo F401RE (only one LED, inverted)
00020  *  
00021  * Some boards use D13 for an LED signal, so this example uses the second 
00022  *   row (row B, pins 7 through 12) of the Pmod connector.  
00023  */
00024 
00025 #include "mbed.h"
00026 #include "ard2pmod.h"
00027 
00028 I2C i2c(D14, D15);
00029 DigitalOut tog(LED1);
00030 DigitalOut als(LED2);
00031 DigitalOut dly(LED3);
00032 DigitalIn pb3(D6);  // Set as input to remove load from PB3
00033 DigitalIn pb4(D7);  // Set as input to remove load from PB4
00034 
00035 const int alsAddr = 0x94;
00036 const int alsLim = 0x0008;
00037 
00038 int main()
00039 {
00040     char cmd[2];
00041     int alsData;
00042 
00043     Ard2Pmod ard2pmd(Ard2Pmod::PMOD_TYPE_I2C_B);  // Configure Ard2Pmod board for I2C on row B
00044 
00045     cmd[0] = 0x02;  // Receive Register
00046     cmd[1] = 0xFC;  // 1.56ms, 1x
00047     i2c.write(alsAddr, cmd, 2);
00048 
00049     cmd[0] = 0x03;  // Transmit Register
00050     cmd[1] = 0x0F;  // 110mA
00051     i2c.write(alsAddr, cmd, 2);
00052     
00053     cmd[0] = 0x01;  // Config Register
00054     cmd[1] = 0x10;  // ALS/Prox Mode
00055     i2c.write(alsAddr, cmd, 2);
00056 
00057     bool lastProx = false;
00058     int offDelay = 0;
00059     tog = false;
00060     als = false;
00061     dly = false;
00062 
00063     while (true) {
00064         wait (0.02);
00065         cmd[0] = 0x05; // ALS Data Register Low
00066         i2c.write(alsAddr, cmd, 1, true);
00067         i2c.read(alsAddr, cmd, 1);
00068         alsData = cmd[0];
00069         als = (alsData < alsLim);
00070 
00071         cmd[0] = 0x16; // Prox Data Register
00072         i2c.write(alsAddr, cmd, 1, true);
00073         i2c.read(alsAddr, cmd, 1);
00074         if (cmd[0]) {
00075             if (!lastProx) {
00076                 tog = !tog;
00077             }
00078             lastProx = true;
00079             offDelay = 250;
00080             dly = false;
00081         } else {
00082             lastProx = false;
00083         }
00084         if (offDelay > 0) { offDelay -= 1; }
00085         else { dly = true; }
00086     }
00087 }