Gert Jan Schoneveld
Tests forked Keypad library.
Dependencies: FPointer keypad mbed
Schematic:
No extra hardware is needed besides the wires and switches. The columns are outputs configured with open drain. The rows are inputs configured with pull up resistors. A key press pulls down its row. With scanning the column is determined thereafter.
See keypad for the forked library used in this project.
Diff: main.cpp
- Revision:
- 0:5410e5950602
- Child:
- 1:8bbe2b267de6
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp Fri Nov 02 22:52:44 2012 +0000
@@ -0,0 +1,57 @@
+#include "mbed.h"
+#include "keypad.h"
+
+#define KEYLEN 4
+#define ENDKEY 15
+char Buffer[KEYLEN];
+int Index = 0;
+
+// Define your own keypad values
+char Keytable[] = { '1', '2', '3', 'A',
+ '4', '5', '6', 'B',
+ '7', '8', '9', 'C',
+ '*', '0', '#', 'D'
+ };
+
+uint32_t cbAfterInput(uint32_t key)
+{
+ bool finish = false;
+
+ printf("Index:%d => Key:%c\n", Index, Keytable[key]);
+
+ if (Index < KEYLEN - 1) {
+ if (key != ENDKEY) // Terminating key
+ Buffer[Index] = Keytable[key];
+ else // Terminating key is entered
+ finish = true;
+ Index++;
+ }
+
+ if (finish || (Index == KEYLEN - 1)) {
+ printf("Complete string = %s\n", Buffer);
+ memset(&Buffer, 0, KEYLEN);
+ Index = 0;
+ }
+
+ return 0;
+}
+
+void Sleep(void)
+{
+ __WFI();
+}
+
+int main()
+{
+ printf("*** Keypad Demo ***\n");
+
+ memset(&Buffer, 0, KEYLEN);
+ Index = 0;
+ Keypad keypad(p25, p26, p27, p28, p21, p22, p23, p24);
+ keypad.CallAfterInput(&cbAfterInput);
+
+ keypad.Start();
+ while (1) {
+ Sleep();
+ }
+}
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