Wouter van Kleunen / SoftI2C-pullup

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API Documentation at this revision

Revision 2:7e8f03569953, committed 2019-05-29

Comitter:
wkleunen
Date:
Wed May 29 06:37:22 2019 +0000
Parent:
1:05473196d133
Commit message:
Enable pull up on softi2c

Changed in this revision

SoftI2C.cpp Show annotated file Show diff for this revision Revisions of this file 
--- a/SoftI2C.cpp	Mon Nov 28 19:55:30 2016 +0000
+++ b/SoftI2C.cpp	Wed May 29 06:37:22 2019 +0000
@@ -2,10 +2,11 @@
 
 SoftI2C::SoftI2C(PinName sda, PinName scl) : _sda(sda), _scl(scl) {
     // Set defaults
-    _sda.mode(PullNone);
-    _scl.mode(PullNone);
     _sda.input();
     _scl.input();
+    _sda.mode(PullUp);
+    _scl.mode(PullUp);
+  
     frequency(100000);
     
     active = false;
@@ -106,6 +107,7 @@
         //Change SDA depending on the bit
         if ( (data >> i) & 0x01 ) {
             _sda.input();
+            _sda.mode(PullUp);
         } else {
             _sda.output();
             _sda.write(0);
@@ -122,6 +124,7 @@
     wait_us(delay_us);
     
     _sda.input();
+    _sda.mode(PullUp);
     wait_us(delay_us);
     
     _scl.write(1);
@@ -136,6 +139,7 @@
     if (active) { //if repeated start
         //Set SDA high, toggle scl
         _sda.input();
+        _sda.mode(PullUp);
         _scl.output();
         _scl.write(0);
         wait_us(delay_us << 1);
@@ -157,8 +161,10 @@
     _sda.write(0);
     wait_us(delay_us);
     _scl.input();
+    _scl.mode(PullUp);
     wait_us(delay_us);
     _sda.input();
+    _sda.mode(PullUp);
     wait_us(delay_us);
     
     active = false;