Forked MMA7660 , extend implementation by using i2c asynch API, to sleep while waiting for transfer -> blocking asynch :-D

Fork of MMA7660 by Erik -

Files at this revision

API Documentation at this revision

Comitter:
Kojto
Date:
Tue May 05 07:23:40 2015 +0000
Parent:
4:36a163511e34
Commit message:
Support I2C Asynch API

Changed in this revision

MMA7660.cpp Show annotated file Show diff for this revision Revisions of this file
MMA7660.h Show annotated file Show diff for this revision Revisions of this file
diff -r 36a163511e34 -r 556829f081f6 MMA7660.cpp
--- a/MMA7660.cpp	Tue May 13 18:14:34 2014 +0000
+++ b/MMA7660.cpp	Tue May 05 07:23:40 2015 +0000
@@ -1,18 +1,38 @@
 #include "MMA7660.h"
 
-MMA7660::MMA7660(PinName sda, PinName scl, bool active) : _i2c(sda, scl)
+MMA7660::MMA7660(PinName sda, PinName scl, bool active, bool asynch) : _i2c(sda, scl), callback_done(false), asynch(asynch)
 {
+    event.attach(this, &MMA7660::callback);
     setActive(active);
     samplerate = 64;
 }
 
+void MMA7660::callback(int event)
+{
+    if (event == I2C_EVENT_TRANSFER_COMPLETE) {
+        callback_done = true;
+    } else {
+        // handling errors
+    }
+}
+
 //Since the MMA lacks a WHO_AM_I register, we can only check if there is a device that answers to the I2C address
 bool MMA7660::testConnection( void )
 {
-    if (_i2c.write(MMA7660_ADDRESS, NULL, 0) == 0 )
-        return true;
-    else
-        return false;
+    if (!asynch) {
+        if (_i2c.write(MMA7660_ADDRESS, NULL, 0) == 0 )
+            return true;
+        else
+            return false;
+    } else {
+        callback_done = false;
+        char received = 0;
+        _i2c.transfer(MMA7660_ADDRESS, NULL, 0, &received, 1, event, I2C_EVENT_ALL, false);
+        while (!callback_done) {
+            sleep();
+        }
+        return received == 0 ? true : false;
+    }
 }
 
 void MMA7660::setActive(bool state)
@@ -150,21 +170,49 @@
     temp[0]=address;
     temp[1]=data;
 
-    _i2c.write(MMA7660_ADDRESS, temp, 2);
+    if (!asynch) {
+        _i2c.write(MMA7660_ADDRESS, temp, 2);
+    } else {
+        callback_done = false;
+        _i2c.transfer(MMA7660_ADDRESS, &temp[0], 2, NULL, 0, event, I2C_EVENT_ALL);
+        while (!callback_done) {
+            sleep();
+        }
+    }
 }
 
 char MMA7660::read(char address)
 {
-    char retval;
-    _i2c.write(MMA7660_ADDRESS, &address, 1, true);
-    _i2c.read(MMA7660_ADDRESS, &retval, 1);
-    return retval;
+    if (!asynch) {
+        char retval;
+
+        _i2c.write(MMA7660_ADDRESS, &address, 1, true);
+        _i2c.read(MMA7660_ADDRESS, &retval, 1);
+        return retval;
+    } else {
+        callback_done = false;
+        char received = 0;
+        char addr = address;
+        _i2c.transfer(MMA7660_ADDRESS, &addr, 1, &received, 1, event, I2C_EVENT_ALL);
+        while (!callback_done) {
+            sleep();
+        }
+        return received;
+    }
 }
 
 void MMA7660::read(char address, char *data, int length)
 {
-    _i2c.write(MMA7660_ADDRESS, &address, 1, true);
-    _i2c.read(MMA7660_ADDRESS, data, length);
+    if (!asynch) {
+        _i2c.write(MMA7660_ADDRESS, &address, 1, true);
+        _i2c.read(MMA7660_ADDRESS, data, length);
+    } else {
+        callback_done = false;
+        _i2c.transfer(MMA7660_ADDRESS, &address, 1, data, length, event, I2C_EVENT_ALL);
+        while (!callback_done) {
+            sleep();
+        }
+    }
 }
 
 float MMA7660::getSingle( int number )
@@ -191,4 +239,4 @@
         setActive(false);
 
     return temp / MMA7660_SENSITIVITY;
-}
\ No newline at end of file
+}
diff -r 36a163511e34 -r 556829f081f6 MMA7660.h
--- a/MMA7660.h	Tue May 13 18:14:34 2014 +0000
+++ b/MMA7660.h	Tue May 05 07:23:40 2015 +0000
@@ -83,8 +83,9 @@
     * @param sda - I2C data pin
     * @param scl - I2C clock pin
     * @param active - true (default) to enable the device, false to keep it standby
+    * @param asynch - use asynch i2c - the API is blocking which does not break the current app
     */
-    MMA7660(PinName sda, PinName scl, bool active = true);
+    MMA7660(PinName sda, PinName scl, bool active = true, bool asynch = false);
 
     /**
     * Tests if communication is possible with the MMA7660
@@ -168,6 +169,8 @@
 
 private:
 
+    void callback(int event);
+
     /**
     * Writes data to the device
     *
@@ -201,6 +204,9 @@
     I2C _i2c;
     bool active;
     float samplerate;
+    volatile bool callback_done;
+    event_callback_t event;
+    const bool asynch;
 };