Diff: Keypad.cpp

Revision:

0:7da3ab010a87

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Keypad.cpp	Mon May 06 10:27:01 2019 +0000
@@ -0,0 +1,124 @@
+#include "Keypad.h"
+
+Keypad::Keypad(
+    PinName kq, PinName kx, PinName ky, PinName kz,
+    PinName ka, PinName kb, PinName kc, PinName kd
+)
+{
+    k_in[0]  = new DigitalIn (ka, PullUp);
+    k_in[1]  = new DigitalIn (kb, PullUp);
+    k_in[2]  = new DigitalIn (kc, PullUp);
+    k_in[3]  = new DigitalIn (kd, PullUp);
+    
+    k_out[0] = new DigitalOut (kq);
+    k_out[1] = new DigitalOut (kx);
+    k_out[2] = new DigitalOut (ky);
+    k_out[3] = new DigitalOut (kz);
+    
+    *k_out[0] = 1;
+    *k_out[1] = 1;
+    *k_out[2] = 1;
+    *k_out[3] = 1;
+    
+    uint8_t j,i;
+    for (j = 0; j < 4; j++){
+        for(i = 0; i < 4; i++){
+            key_transent_cntr[j][i] = CHNG_CNT;
+            key_state[j][i] = Off_state;
+        }
+    }
+    for(i = 0; i < BF_SIZE; i++){
+        buf[i] = 0;
+    }
+    read_addr = 0;
+    write_addr = 0;
+    tk.attach_us(callback(this, &Keypad::key_scan), 2000);     // 2mS
+}
+
+void Keypad::key_scan(void)
+{
+    //my_led = 1;
+    for (int32_t j = 0; j < 4; j++){
+        *k_out[0] = 1;   *k_out[1] = 1;  *k_out[2] = 1; *k_out[3] = 1;
+        *k_out[j] = 0;
+        wait_us(1);
+        for (int32_t i = 0; i < 4; i++){
+            switch (key_state[j][i]){
+                case Off_state:
+                    //my_led = 1;
+                    if (*k_in[i] == 0){ // key on
+                        key_state[j][i] = Off_to_on_transient;
+                        key_transent_cntr[j][i] = CHNG_CNT;
+                    }
+                    break;
+                case Off_to_on_transient:
+                    //my_led = 1;
+                    if (*k_in[i] == 0){ // key on
+                        if (--key_transent_cntr[j][i] < -CHNG_CNT){
+                            //my_led = 1;
+                            bf_put(j * 4 + i + 1); // save data into buffer
+                            key_state[j][i] = On_state;
+                        }
+                    } else {    // key off
+                        if (++key_transent_cntr[j][i] > CHNG_CNT){
+                            key_state[j][i] = Off_state;
+                        }
+                    }
+                    break;
+                case On_state:
+                    //my_led = 1;
+                    if (*k_in[i] == 1){ // key off
+                        key_state[j][i] = On_to_off_transient;
+                        key_transent_cntr[j][i] = -CHNG_CNT;
+                    }
+                    break;
+                case On_to_off_transient:
+                    //my_led = 1;
+                    if (*k_in[i] == 0){ // key on
+                        if (--key_transent_cntr[j][i] < -CHNG_CNT){
+                            key_state[j][i] = On_state;
+                        }
+                    } else {    // key off
+                        if (++key_transent_cntr[j][i] > CHNG_CNT){
+                            key_state[j][i] = Off_state;
+                        }
+                    }
+                    break;
+                default:    // just in case
+                    key_state[j][i] = Off_state;
+                    break;
+            }
+            //my_led = 0;
+        }
+    }
+    *k_out[0] = 1;   *k_out[1] = 1;  *k_out[2] = 1; *k_out[3] = 1;
+    //my_led = 0;
+}
+
+uint8_t Keypad::read(void)
+{
+    return bf_get();
+}
+
+void Keypad::bf_put(char dt)
+{
+    uint8_t next = write_addr + 1;
+    if (next == BF_SIZE) {
+        next = 0;
+    }
+    buf[write_addr] = dt;
+    write_addr = next;
+}
+
+int8_t Keypad::bf_get (void){
+    if (read_addr == write_addr){
+        return 0;
+    }
+    uint8_t dt = buf[read_addr];
+    ++read_addr;
+    if (read_addr == BF_SIZE){
+        read_addr = 0;
+    }
+    return dt;
+}
+