IOExpander: add readAll() API

Author: facchinm

examples/Digital_programmable/Digital_input/Digital_input.ino

@@ -28,7 +28,7 @@ void setup() {
 }
 
 void loop() {
-  //Reads and Prints all channels and 
+  //Reads and Prints all channels (in a single operation)
   readAll();
 
   //Read one-by-one each channel and print them one-by-one
@@ -62,13 +62,14 @@ void loop() {
 }
 
 uint8_t readAll() {
-  Serial.println("CH00: " + String(digital_inputs.read(DIN_READ_CH_PIN_00)));
-  Serial.println("CH01: " + String(digital_inputs.read(DIN_READ_CH_PIN_01)));
-  Serial.println("CH02: " + String(digital_inputs.read(DIN_READ_CH_PIN_02)));
-  Serial.println("CH03: " + String(digital_inputs.read(DIN_READ_CH_PIN_03)));
-  Serial.println("CH04: " + String(digital_inputs.read(DIN_READ_CH_PIN_04)));
-  Serial.println("CH05: " + String(digital_inputs.read(DIN_READ_CH_PIN_05)));
-  Serial.println("CH06: " + String(digital_inputs.read(DIN_READ_CH_PIN_06)));
-  Serial.println("CH07: " + String(digital_inputs.read(DIN_READ_CH_PIN_07)));
+  uint32_t inputs = digital_inputs.readAll();
+  Serial.println("CH00: " + String((inputs & (1 << DIN_READ_CH_PIN_00)) >> DIN_READ_CH_PIN_00));
+  Serial.println("CH01: " + String((inputs & (1 << DIN_READ_CH_PIN_01)) >> DIN_READ_CH_PIN_01));
+  Serial.println("CH02: " + String((inputs & (1 << DIN_READ_CH_PIN_02)) >> DIN_READ_CH_PIN_02));
+  Serial.println("CH03: " + String((inputs & (1 << DIN_READ_CH_PIN_03)) >> DIN_READ_CH_PIN_03));
+  Serial.println("CH04: " + String((inputs & (1 << DIN_READ_CH_PIN_04)) >> DIN_READ_CH_PIN_04));
+  Serial.println("CH05: " + String((inputs & (1 << DIN_READ_CH_PIN_05)) >> DIN_READ_CH_PIN_05));
+  Serial.println("CH06: " + String((inputs & (1 << DIN_READ_CH_PIN_06)) >> DIN_READ_CH_PIN_06));
+  Serial.println("CH07: " + String((inputs & (1 << DIN_READ_CH_PIN_07)) >> DIN_READ_CH_PIN_07));
   Serial.println();
 }

src/utility/ioexpander/ArduinoIOExpander.cpp

@@ -83,6 +83,14 @@ int ArduinoIOExpanderClass::read(int pin)
   return -1;
 }
 
+uint32_t ArduinoIOExpanderClass::readAll()
+{
+  uint8_t banks[3];
+  _tca.readAll(banks);
+  return *(uint32_t*)banks;
+}
+
+
 void ArduinoIOExpanderClass::initPins()
 {
 

src/utility/ioexpander/ArduinoIOExpander.h

@@ -79,6 +79,7 @@ class ArduinoIOExpanderClass {
     bool set(int pin, int status) { return set( pin, (PinStatus)status); };
 
     int read(int pin);
+    uint32_t readAll();
     bool pinMode(int pin, PinMode direction);
 
 private:

src/utility/ioexpander/TCA6424A.cpp

@@ -87,7 +87,7 @@ uint8_t TCA6424A::readBank(uint8_t bank) {
  * @param banks Container for all bank's pin values (P00-P27)
  */
 void TCA6424A::readAll(uint8_t *banks) {
-    I2Cdev::readBytes(devAddr, TCA6424A_RA_INPUT0, 3, banks);
+    I2Cdev::readBytes(devAddr, TCA6424A_RA_INPUT0 | TCA6424A_AUTO_INCREMENT, 3, banks);
 }
 /** Get all pin logic levels from all banks.
  * Reads into individual 1-byte containers.
@@ -96,7 +96,7 @@ void TCA6424A::readAll(uint8_t *banks) {
  * @param bank2 Container for Bank 2's pin values (P20-P27)
  */
 void TCA6424A::readAll(uint8_t *bank0, uint8_t *bank1, uint8_t *bank2) {
-    I2Cdev::readBytes(devAddr, TCA6424A_RA_INPUT0, 3, buffer);
+    I2Cdev::readBytes(devAddr, TCA6424A_RA_INPUT0 | TCA6424A_AUTO_INCREMENT, 3, buffer);
     *bank0 = buffer[0];
     *bank1 = buffer[1];
     *bank2 = buffer[2];