Fixed LTR553 Interrupt

lewisxhe · Oct 17, 2023 · d0f26c3 · d0f26c3
1 parent d761ad1
commit d0f26c3
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Showing 2 changed files with 36 additions and 22 deletions.
diff --git a/examples/LTR553ALS_Sensor/LTR553ALS_Sensor.ino b/examples/LTR553ALS_Sensor/LTR553ALS_Sensor.ino
@@ -68,7 +68,7 @@ void setup()
 
     // Set the high and low thresholds of the proximity sensor.
     // If the value exceeds or falls below the set value, an interrupt will be triggered.
-    // als.setProximityThreshold(10, 30);
+    als.setProximityThreshold(10, 30);
 
     // Controls the Light Sensor N number of times the measurement data is outside the range
     // defined by the upper and lower threshold limits before asserting the interrupt.
@@ -147,26 +147,46 @@ void setup()
     // Number of pulses
     als.setPsLedPulses(1);
 
+    // Enable proximity sensor saturation indication
+    als.enablePsIndicator();
+
     // Enable ambient light sensor
     als.enableLightSensor();
 
     // Enable proximity sensor
     als.enableProximity();
 
-    // Enable proximity sensor saturation indication
-    als.enablePsIndicator();
 }
 
+bool canRead()
+{
+#if SENSOR_IRQ != -1
+    return digitalRead(SENSOR_IRQ) == LOW;
+#else
+    static uint32_t lastReadMillis;
+    if (millis() > lastReadMillis) {
+        lastReadMillis = millis() + 500;
+        return true;
+    }
+    return false;
+#endif
+}
 
 void loop()
 {
+    /*
+    * PS Saturation Flag is used for monitoring the internal IC saturation.
+    * It will be flagged when the IC has reached saturation
+    * and not able to perform any further PS measurement
+    * */
     bool saturated;
-    Serial.print(" IRQ:"); Serial.print (digitalRead(SENSOR_IRQ));
-    Serial.print(" ALS: CH1:"); Serial.print(als.getLightSensor(1));
-    Serial.print(" -  CH0:"); Serial.print(als.getLightSensor(0));
-    Serial.print(" -  PS:"); Serial.print(als.getProximity(&saturated));
-    Serial.print(" -  "); Serial.println(saturated ? "PS saturated" : "PS not saturated");
-    delay(500);
+    if (canRead()) {
+        Serial.print(" ALS: CH1:"); Serial.print(als.getLightSensor(1));
+        Serial.print(" -  CH0:"); Serial.print(als.getLightSensor(0));
+        Serial.print(" -  PS:"); Serial.print(als.getProximity(&saturated));
+        Serial.print(" -  "); Serial.println(saturated ? "PS saturated" : "PS not saturated");
+    }
+    delay(5);
 }
 
 

diff --git a/src/SensorLTR553.hpp b/src/SensorLTR553.hpp
@@ -42,7 +42,7 @@ class SensorLTR553 :
         ALS_IRQ_ACTIVE_HIGH // INT pin is considered active when it is a logic 1
     };
     enum IrqMode {
-        ALS_IRQ_ONLY_PS,    // Only PS measurement can trigger interrupt
+        ALS_IRQ_ONLY_PS = 1,    // Only PS measurement can trigger interrupt
         ALS_IRQ_ONLY_ALS,   // Only ALS measurement can trigger interrupt
         ALS_IRQ_BOTH,       // Both ALS and PS measurement can trigger interrupt
     };
@@ -235,21 +235,15 @@ class SensorLTR553 :
     // defined by the upper and lower threshold limits before asserting the interrupt.
     void setProximityPersists(uint8_t count)
     {
-        writeRegister(LTR553_REG_INTERRUPT_PERSIST, 0x0F, count - 1);
+        writeRegister(LTR553_REG_INTERRUPT_PERSIST, 0x0F, count == 0 ? 0 : count - 1);
     }
 
     void setProximityThreshold(uint16_t low, uint16_t high)
     {
-        uint8_t buffer[4] = {
-            (uint8_t)(high & 0xFF),
-            (uint8_t)((high >> 8) & 0xFF),
-            (uint8_t)(low & 0xFF),
-            (uint8_t)((low >> 8) & 0xFF),
-        };
-        writeRegister(LTR553_REG_PS_THRES_UP_0, (uint8_t)(high & 0xFF));
-        writeRegister(LTR553_REG_PS_THRES_UP_1, (uint8_t)((high >> 8) & 0xFF) & 0x03);
-        writeRegister(LTR553_REG_PS_THRES_LOW_0, (uint8_t)(low & 0xFF));
-        writeRegister(LTR553_REG_PS_THRES_LOW_1, (uint8_t)((low >> 8) & 0xFF) & 0x03);
+        writeRegister(LTR553_REG_PS_THRES_UP_0, lowByte(high));
+        writeRegister(LTR553_REG_PS_THRES_UP_1, lowByte(high >> 8) & 0x0F);
+        writeRegister(LTR553_REG_PS_THRES_LOW_0, lowByte(low));
+        writeRegister(LTR553_REG_PS_THRES_LOW_1, lowByte(low >> 8) & 0x0F);
     }
 
     void setProximityRate(PsRate rate)
@@ -277,7 +271,7 @@ class SensorLTR553 :
         clrRegisterBit(LTR553_REG_PS_CONTR, 5);
     }
 
-    int getProximity(bool *saturated )
+    int getProximity(bool *saturated = NULL )
     {
         uint8_t buffer[2] = {0};
         int val = readRegister(LTR553_REG_PS_DATA_0, buffer, 2);