Gert Jan Schoneveld / Mbed 2 deprecated SaveKeypad

Tests forked Keypad library.

Dependencies:   FPointer keypad mbed

Schematic:

http://schind.nl/keypad.png

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.

main.cpp

Committer:
gj_schoneveld
Date:
2012-11-02
Revision:
0:5410e5950602
Child:
1:8bbe2b267de6

File content as of revision 0:5410e5950602:

#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();
    }
}