Simblee For Mobile Color Sensor

BH1745 Color Sensor

A Work In Progress, albeit, not by much!

My attempt to interface the BH1745 Color Sensor to Simblee. I originally made the shield to interface to RFduino. But thought it would be more interesting to use it in conjunction with Simblee For Mobile. My intent was to display on the smart device the color detected by the remote Simblee based color sensor. The color sensor is BH1745 from Rohm Semiconductor. It uses I2C protocol to communicate. Resistors R1 and R2 are pullups for the I2C bus. I am using the internal pullups on the Simblee's Nordic nRF51822 SOC.   While the UI part of this project works, I don't quite understand the algorithm needed to get a perfect representation of the color. But here it is if you want to use it as a starting point.

BH1745ColorSensor.ino BH1745ColorSensor.ino // ColorSensor BH1745 // Thomas Olson teo20160813.01 // Test BH1745 I2C #include <SimbleeForMobile.h> #include <Wire.h> #define bh1745 0x38 // default address #define DEBUG 1 uint8_t red_lo = 0; uint8_t red_hi = 0; uint8_t green_lo = 0; uint8_t green_hi = 0; uint8_t blue_lo = 0; uint8_t blue_hi = 0; uint8_t clear_lo = 0; uint8_t clear_hi = 0; uint16_t red = 0; uint16_t green = 0; uint16_t blue = 0; uint16_t cclear = 0; uint32_t hypo = 0UL; uint8_t ared = 0; uint8_t agreen = 0; uint8_t ablue = 0; uint8_t colorBarID; uint8_t buttonID; uint8_t textID; void setup() { if(DEBUG)Serial.begin(9600); if(DEBUG)printf("\nBH1745 Color Sensor\n"); Wire.begin(); // default SCL = 5, SDA = 6 //Wire.beginOnPins(2,3); // Initialize the BH1745 // Persistence Wire.beginTransmission(bh1745); Wire.write(0x61); Wire.write(0x03); // interrupt if 8 consecutive values Wire.endTransmission(); // Mode Control 1 Wire.beginTransmission(bh1745); Wire.write(0x41); Wire.write(0x00); // 160ms measurement time Wire.endTransmission(); // Mode Control 2 Wire.beginTransmission(bh1745); Wire.write(0x42); Wire.write(0x92); // validity and enable and gain=16 Wire.endTransmission(); // Mode Control 3 Wire.beginTransmission(bh1745); Wire.write(0x44); Wire.write(0x02); // ??? Wire.endTransmission(); SimbleeForMobile.deviceName = "BH1745"; SimbleeForMobile.advertisementData = "color"; SimbleeForMobile.begin(); } void loop() { SimbleeForMobile.process(); } void updateColorBar1() { int retval; char updateText[80]; Wire.beginTransmission(bh1745); Wire.write(0x50); Wire.endTransmission(); retval = Wire.requestFrom(bh1745,8); if(8 <= retval) { red_lo = Wire.read(); red_hi = Wire.read(); green_lo = Wire.read(); green_hi = Wire.read(); blue_lo = Wire.read(); blue_hi = Wire.read(); clear_lo = Wire.read(); clear_hi = Wire.read(); Wire.endTransmission(); red = (red_hi << 8) | red_lo; green = (green_hi << 8) | green_lo; blue = (blue_hi << 8) | blue_lo; cclear = (clear_hi << 8) | clear_lo; if(DEBUG)printf("R: %u, G: %u, B: %u, C: %u\n",red,green,blue,cclear); // adjust for sensitivity differences red = (red * 1.39); green = (green * 1.00); blue = (blue * 1.79); hypo = (uint32_t)sqrt((uint32_t)(red*red) + (uint32_t)(green*green) + (uint32_t)(blue*blue)); if(DEBUG)printf("R: %u, G: %u, B: %u, C: %u, H:%lu\n",red,green,blue,cclear,hypo); ared = map(red, 0,hypo, 0,255); agreen = map(green, 0,hypo, 0,255); ablue = map(blue, 0,hypo, 0,255); if(DEBUG)printf("aR: %u, aG: %u, aB: %u\n",ared,agreen,ablue); if(hypo < 50UL) { ared = 0; agreen = 0; ablue = 0; } sprintf(updateText,"R: %u, G: %u, B: %u, C: %u, H:%lu\naR: %u, aG: %u, aB: %u",red,green,blue,cclear,hypo,ared,agreen,ablue); SimbleeForMobile.updateText(textID,updateText); SimbleeForMobile.updateColor(colorBarID,rgb(ared,agreen,ablue)); }else { if(DEBUG)printf("RetVal: %d\n",retval); } } void updateColorBar2() { int retval; char updateText[80]; float fmax; float fred = 0.0; float fgreen = 0.0; float fblue = 0.0; Wire.beginTransmission(bh1745); Wire.write(0x50); Wire.endTransmission(); retval = Wire.requestFrom(bh1745,8); if(8 <= retval) { red_lo = Wire.read(); red_hi = Wire.read(); green_lo = Wire.read(); green_hi = Wire.read(); blue_lo = Wire.read(); blue_hi = Wire.read(); clear_lo = Wire.read(); clear_hi = Wire.read(); Wire.endTransmission(); red = (red_hi << 8) | red_lo; green = (green_hi << 8) | green_lo; blue = (blue_hi << 8) | blue_lo; cclear = (clear_hi << 8) | clear_lo; if(DEBUG)printf("R: %d, G: %d, B: %d, C: %d\n",red,green,blue,cclear); // adjust for sensitivity differences fred = red * 1.39; fgreen = green * 1.00; fblue = blue * 1.79; if(DEBUG)printf("R: %d, G: %d, B: %d, C: %d\n",fred,fgreen,fblue,cclear); // find max color if(fred >= fgreen && fred >= fblue) fmax = fred; else if(fgreen >= fred && fgreen >= fblue) fmax = fgreen; else fmax = fblue; ared = (fred/fmax) * 255; agreen = (fgreen/fmax) * 255; ablue = (fblue/fmax) * 255; if(DEBUG)printf("aR: %d, aG: %d, aB: %d\n",ared,agreen,ablue); if(fmax < 50) { ared = 0; agreen = 0; ablue = 0; } sprintf(updateText,"R: %u, G: %u, B: %u, C: %u\naR: %u, aG: %u, aB: %u",red,green,blue,cclear,ared,agreen,ablue); SimbleeForMobile.updateText(textID,updateText); SimbleeForMobile.updateColor(colorBarID,rgb(ared,agreen,ablue)); }else { if(DEBUG)printf("RetVal: %d\n",retval); } }

p3_UI.ino p3_UI.ino void ui() { SimbleeForMobile.beginScreen(WHITE); SimbleeForMobile.drawText(20,50, "BH1745 Color Sensor Test"); colorBarID = SimbleeForMobile.drawRect(20,80,200,30, BLACK); textID = SimbleeForMobile.drawText(20,140,"R: 0, G: 0, B: 0, C: 0"); buttonID = SimbleeForMobile.drawButton(20,200,100,"Get Color",BLACK); SimbleeForMobile.endScreen(); } void ui_event(event_t &event) { // Will any tap on the screen trigger an event? Nope // So test for tap on colorBar if(event.id == buttonID){ if(DEBUG)printf("Tap-Tap\n"); updateColorBar2(); //alogrithm 1 or 2 } }

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