From 694010c57bd25c63de31fafd42e0d9864dec7148 Mon Sep 17 00:00:00 2001
From: ladyada <limor@ladyada.net>
Date: Thu, 7 Mar 2019 14:23:42 -0500
Subject: [PATCH] create an i2c device with an address and be able to detect it

---
 Adafruit_I2CDevice.cpp                        | 33 +++++++++++++++++++
 Adafruit_I2CDevice.h                          | 15 +++++++++
 .../i2c_address_detect/i2c_address_detect.ino | 21 ++++++++++++
 3 files changed, 69 insertions(+)
 create mode 100644 examples/i2c_address_detect/i2c_address_detect.ino

diff --git a/Adafruit_I2CDevice.cpp b/Adafruit_I2CDevice.cpp
index e69de29..e0e6afc 100644
--- a/Adafruit_I2CDevice.cpp
+++ b/Adafruit_I2CDevice.cpp
@@ -0,0 +1,33 @@
+#include <Adafruit_I2CDevice.h>
+#include <Arduino.h>
+
+Adafruit_I2CDevice::Adafruit_I2CDevice(uint8_t addr, TwoWire *theWire) {
+  _addr = addr;
+  _wire = theWire;
+  _begun = false;
+}
+
+bool Adafruit_I2CDevice::begin(void) {
+  _wire->begin();
+  _begun = true;
+
+  return detected();
+}
+
+bool Adafruit_I2CDevice::detected(void) {
+  // Init I2C if not done yet
+  if (!_begun && !begin()) {
+    return false;
+  }
+
+  // A basic scanner, see if it ACK's
+  _wire->beginTransmission(_addr);
+  if (_wire->endTransmission () == 0) {
+    return true;
+  }
+  return false;
+}
+
+uint8_t Adafruit_I2CDevice::address(void) {
+  return _addr;
+}
diff --git a/Adafruit_I2CDevice.h b/Adafruit_I2CDevice.h
index e69de29..d353329 100644
--- a/Adafruit_I2CDevice.h
+++ b/Adafruit_I2CDevice.h
@@ -0,0 +1,15 @@
+#include <Wire.h>
+
+class Adafruit_I2CDevice {
+
+private:
+  uint8_t _addr;
+  TwoWire *_wire;
+  bool _begun;
+
+public:
+  Adafruit_I2CDevice(uint8_t addr, TwoWire *theWire=&Wire);
+  uint8_t address(void);
+  bool begin(void);
+  bool detected(void);
+};
diff --git a/examples/i2c_address_detect/i2c_address_detect.ino b/examples/i2c_address_detect/i2c_address_detect.ino
new file mode 100644
index 0000000..b150525
--- /dev/null
+++ b/examples/i2c_address_detect/i2c_address_detect.ino
@@ -0,0 +1,21 @@
+#include <Adafruit_I2CDevice.h>
+
+Adafruit_I2CDevice i2c_dev = Adafruit_I2CDevice(0x10);
+
+void setup() {
+  while (!Serial) { delay(10); }
+  Serial.begin(115200);
+  Serial.println("I2C address detection test");
+
+  if (!i2c_dev.begin()) {
+    Serial.print("Did not find device at 0x");
+    Serial.println(i2c_dev.address(), HEX);
+    while (1);
+  }
+  Serial.print("Device found on address 0x");
+  Serial.println(i2c_dev.address(), HEX);
+}
+
+void loop() {
+  
+}