Zhiyong Li / keypad

Updated 4X4 keypad code that works on STM32F407 and Mbed-OS-5. InterruptIn on STM32F4 MCUs seem to float without PullDown/Up, without forced PullDown the original code doesn't work on STM32F407 and most likely other STM32 MCUs as well.

Files at this revision

API Documentation at this revision

Revision 11:75328ab1acf4, committed 2020-01-27

Comitter:
zhiyong
Date:
Mon Jan 27 05:15:16 2020 +0000
Parent:
10:da060f8c03e8
Commit message:
Added PullDown to InterruptIn initialization so the code can work on STM32F4. Also removed debounce delay in ISR to work on mbed-os-5.; ; Tested working on customized boarded based on Arch_Max/STM32F407VET6.

Changed in this revision

Keypad.cpp Show annotated file Show diff for this revision Revisions of this file 
--- a/Keypad.cpp	Wed Jan 01 17:45:53 2014 +0000
+++ b/Keypad.cpp	Mon Jan 27 05:15:16 2020 +0000
@@ -28,19 +28,19 @@
 )
 {
     if (_rows[0]) {
-        _rows[0]->rise(this, &Keypad::_cbRow0Rise);
+        _rows[0]->rise(callback(this, &Keypad::_cbRow0Rise));
     }
 
     if (_rows[1]) {
-        _rows[1]->rise(this, &Keypad::_cbRow1Rise);
+        _rows[1]->rise(callback(this, &Keypad::_cbRow1Rise));
     }
 
     if (_rows[2]) {
-        _rows[2]->rise(this, &Keypad::_cbRow2Rise);
+        _rows[2]->rise(callback(this, &Keypad::_cbRow2Rise));
     }
 
     if (_rows[3]) {
-        _rows[3]->rise(this, &Keypad::_cbRow3Rise);
+        _rows[3]->rise(callback(this, &Keypad::_cbRow3Rise));
     }
 }
 
@@ -68,7 +68,9 @@
     _nRow = 0;
     for (int i = 0; i < 4; i++) {
         if (rPins[i] != NC) {
-            _rows[i] = new InterruptIn(rPins[i]);
+            // PullDown required, otherwise won't work on STM32F407, most likely not on other STM32 MCUs as well
+            // Without PullDown, InterruptIn seems to float
+            _rows[i] = new InterruptIn(rPins[i], PullDown);
             _nRow++;
         } else
             break;
@@ -133,10 +135,12 @@
 ,InterruptIn *therow
 )
 {
+    // Blocking waiting not allowed by mbed-os-5
+    // Keypad seems to work fine without debounce
 #ifdef THREAD_H
-    Thread::wait(_debounce);
+    //Thread::wait(_debounce);
 #else
-    wait_ms(_debounce);
+    //wait_ms(_debounce);
 #endif
 
     if (therow->read() == 0)