Diff: ds18b20/DS1Wire.cpp

Revision:

1:3aec489c7366

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/ds18b20/DS1Wire.cpp	Fri Apr 11 03:35:05 2014 +0000
@@ -0,0 +1,60 @@
+#include "DS1Wire.h"
+#include "mbed.h"
+#include <stdint.h>
+
+// Timing delay for 1-wire serial standard option
+enum DELAY { A = 6, B = 64, C = 60, D = 10, E = 9, F = 55, G = 0, H = 480, I = 70, J = 410 };
+
+   
+int Reset(DigitalInOut& pin) {
+    pin.output();
+    pin = 0;    // drive bus low
+    wait_us(H);
+    pin.input(); // release bus
+    wait_us(I);
+    uint32_t result = pin;  // read bus value
+    wait_us(J);
+    return result;
+}
+
+void WriteBit(DigitalInOut& pin, uint32_t bit) {
+    pin.output();
+    if (bit) {
+        pin = 0;        // drive bus low
+        wait_us(A);        // delay A
+        pin.input();      // release bus
+        wait_us(B);        // delay B
+    } else {
+        pin = 0;    // drive bus low
+        wait_us(C);    // delay C
+        pin.input();  // release bus
+        wait_us(D);    // delay D
+    }
+}
+
+uint32_t ReadBit(DigitalInOut& pin) {
+    uint32_t bit_value;
+    pin.output();
+    pin = 0;        // drive bus low
+    wait_us(A);        // delay A
+    pin.input();      // release bus
+    wait_us(E);        // delay E
+    bit_value  = pin;    // master sample bus
+    wait_us(F);
+    return bit_value;
+}
+
+void WriteByte(DigitalInOut& pin, uint32_t byte) {
+    for (uint32_t bit = 0; bit < 8; ++bit) {
+        WriteBit(pin, byte & 0x01); // lsb to msb
+        byte >>= 1;    // right shift by 1-bit
+    }
+}
+
+uint32_t ReadByte(DigitalInOut& pin) {
+    uint32_t byte = 0;
+    for (uint32_t bit = 0; bit < 8; ++bit) {
+        byte |= (ReadBit(pin) << bit);    // Reads lsb to msb
+    }
+    return byte;
+}
\ No newline at end of file