Diff: grove_digital_light.cpp

Revision:

0:54ed8f245631

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/grove_digital_light.cpp	Tue Jun 09 10:17:49 2015 +0000
@@ -0,0 +1,155 @@
+
+
+#include "suli2.h"
+#include "grove_digital_light.h"
+
+
+
+//local functions
+static void grove_digital_light_getlux(I2C_T *i2c);
+static unsigned long grove_digital_light_calculatelux(unsigned int iGain, unsigned int tInt, int iType);
+
+//local variables
+static unsigned char cmdbuf[2];
+static uint16_t ch0, ch1;
+static unsigned long chScale;
+static unsigned long channel1;
+static unsigned long channel0;
+static unsigned long  ratio1;
+static unsigned int b;
+static unsigned int m;
+static unsigned long temp;
+static unsigned long lux;
+
+
+
+void grove_digital_light_init(I2C_T *i2c, int pinsda, int pinscl)
+{
+    suli_i2c_init(i2c, pinsda, pinscl);
+}
+
+bool grove_digital_light_write_setup(I2C_T *i2c)
+{
+    cmdbuf[0] = TSL2561_Control;
+    cmdbuf[1] = 0x03;
+    suli_i2c_write(i2c, TSL2561_Address, cmdbuf, 2);  // POWER UP
+    cmdbuf[0] = TSL2561_Timing;
+    cmdbuf[1] = 0x00;
+    suli_i2c_write(i2c, TSL2561_Address, cmdbuf, 2);  //No High Gain (1x), integration time of 13ms
+    cmdbuf[0] = TSL2561_Interrupt;
+    cmdbuf[1] = 0x00;
+    suli_i2c_write(i2c, TSL2561_Address, cmdbuf, 2);  
+    cmdbuf[0] = TSL2561_Control;
+    cmdbuf[1] = 0x00;
+    suli_i2c_write(i2c, TSL2561_Address, cmdbuf, 2);  // POWER Down
+    
+    return true;
+}
+
+static void grove_digital_light_getlux(I2C_T *i2c)
+{
+    uint8_t CH0_LOW = 0, CH0_HIGH = 0, CH1_LOW = 0, CH1_HIGH = 0;
+
+    cmdbuf[0] = TSL2561_Channal0L;
+    suli_i2c_write(i2c, TSL2561_Address, cmdbuf, 1);
+    suli_i2c_read(i2c, TSL2561_Address, &CH0_LOW, 1);
+    cmdbuf[0] = TSL2561_Channal0H;
+    suli_i2c_write(i2c, TSL2561_Address, cmdbuf, 1);
+    suli_i2c_read(i2c, TSL2561_Address, &CH0_HIGH, 1);
+    cmdbuf[0] = TSL2561_Channal1L;
+    suli_i2c_write(i2c, TSL2561_Address, cmdbuf, 1);
+    suli_i2c_read(i2c, TSL2561_Address, &CH1_LOW, 1);
+    cmdbuf[0] = TSL2561_Channal1H;
+    suli_i2c_write(i2c, TSL2561_Address, cmdbuf, 1);
+    suli_i2c_read(i2c, TSL2561_Address, &CH1_HIGH, 1);
+
+    ch0 = (CH0_HIGH<<8) | CH0_LOW;
+    ch1 = (CH1_HIGH<<8) | CH1_LOW;
+}
+
+static unsigned long grove_digital_light_calculatelux(unsigned int iGain, unsigned int tInt, int iType)
+{
+    switch (tInt)
+    {
+        case 0:  // 13.7 msec
+            chScale = CHSCALE_TINT0;
+            break;
+        case 1: // 101 msec
+            chScale = CHSCALE_TINT1;
+            break;
+        default: // assume no scaling
+            chScale = (1 << CH_SCALE);
+            break;
+    }
+    if (!iGain)  chScale = chScale << 4; // scale 1X to 16X
+    // scale the channel values
+    channel0 = (ch0 * chScale) >> CH_SCALE;
+    channel1 = (ch1 * chScale) >> CH_SCALE;
+
+    ratio1 = 0;
+    if (channel0!= 0) ratio1 = (channel1 << (RATIO_SCALE+1))/channel0;
+    // round the ratio value
+    unsigned long ratio = (ratio1 + 1) >> 1;
+
+    switch (iType)
+    {
+        case 0: // T package
+            if ((ratio >= 0) && (ratio <= K1T))
+            {b=B1T; m=M1T;}
+            else if (ratio <= K2T)
+            {b=B2T; m=M2T;}
+            else if (ratio <= K3T)
+            {b=B3T; m=M3T;}
+            else if (ratio <= K4T)
+            {b=B4T; m=M4T;}
+            else if (ratio <= K5T)
+            {b=B5T; m=M5T;}
+            else if (ratio <= K6T)
+            {b=B6T; m=M6T;}
+            else if (ratio <= K7T)
+            {b=B7T; m=M7T;}
+            else if (ratio > K8T)
+            {b=B8T; m=M8T;}
+            break;
+        case 1:// CS package
+            if ((ratio >= 0) && (ratio <= K1C))
+            {b=B1C; m=M1C;}
+            else if (ratio <= K2C)
+            {b=B2C; m=M2C;}
+            else if (ratio <= K3C)
+            {b=B3C; m=M3C;}
+            else if (ratio <= K4C)
+            {b=B4C; m=M4C;}
+            else if (ratio <= K5C)
+            {b=B5C; m=M5C;}
+            else if (ratio <= K6C)
+            {b=B6C; m=M6C;}
+            else if (ratio <= K7C)
+            {b=B7C; m=M7C;}
+    }
+    temp=((channel0*b)-(channel1*m));
+    if(temp<0) temp=0;
+    temp+=(1<<(LUX_SCALE-1));
+    // strip off fractional portion
+    lux=temp>>LUX_SCALE;
+    return (lux);
+}
+
+bool grove_digital_light_readvisiblelux(I2C_T *i2c, uint32_t *lux)
+{
+    cmdbuf[0] = TSL2561_Control;
+    cmdbuf[1] = 0x03;
+    suli_i2c_write(i2c, TSL2561_Address, cmdbuf, 2);  // POWER UP
+    suli_delay_ms(14);
+    grove_digital_light_getlux(i2c);
+
+    cmdbuf[0] = TSL2561_Control;
+    cmdbuf[1] = 0x00;
+    suli_i2c_write(i2c, TSL2561_Address, cmdbuf, 2);  // POWER Down
+    if(ch0/ch1 < 2 && ch0 > 4900)
+    {
+        return -1;  //ch0 out of range, but ch1 not. the lux is not valid in this situation.
+    }
+    *lux = grove_digital_light_calculatelux(0, 0, 0);  //T package, no gain, 13ms
+    return true;
+}