Revision 0:4f399e4b64a9, committed 2013-08-23

Comitter:

Renato

Date:

Fri Aug 23 08:36:59 2013 +0000

Commit message:

Function to read ibutton serial & family

Changed in this revision

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/DS1Wire.cpp	Fri Aug 23 08:36:59 2013 +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

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/DS1Wire.h	Fri Aug 23 08:36:59 2013 +0000
@@ -0,0 +1,15 @@
+#ifndef __DS_1_WIRE__
+#define __DS_1_WIRE__
+#include <stdint.h>
+#include "mbed.h"
+
+int Reset(DigitalInOut& pin);
+
+void WriteBit(DigitalInOut& pin, uint32_t bit);
+uint32_t ReadBit(DigitalInOut& pin);
+
+void WriteByte(DigitalInOut& pin, uint32_t byte);
+uint32_t ReadByte(DigitalInOut& pin);
+
+
+#endif
\ No newline at end of file

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/ds1990.cpp	Fri Aug 23 08:36:59 2013 +0000
@@ -0,0 +1,87 @@
+#include "ds1990.h"
+#include "DS1Wire.h"
+#include "mbed.h"
+#include <stdint.h>
+
+// Device byte commands over 1-wire serial
+enum COMMANDS { READ_ROM = 0x33, CONVERT = 0x44, READ_SCRATCHPAD = 0xBE,  SKIP_ROM = 0xCC };
+
+
+// device onboard register layout
+typedef struct {
+    uint8_t    LSB;
+    uint8_t    MSB;
+    uint8_t    Th;
+    uint8_t    Tl;
+    uint8_t    config;
+    uint8_t    reserved0xFF;
+    uint8_t    reserved0xCH;
+    uint8_t    reserved0x10;
+    uint8_t    CRC;
+} ScratchPad_t;
+
+
+DigitalOut conversionInProgress(LED4);  // conversion in progress
+DigitalOut resetFailure(LED1);          // for error reporting
+extern DigitalInOut sensor;     // sensor pin
+
+static void inError() {
+    while (1) {
+        resetFailure = !resetFailure;
+        wait(0.2);
+    }
+}
+
+void DoConversion() {
+    if (Reset(sensor) != 0) {
+        inError();
+    } else {
+        conversionInProgress = 1;       // led on
+        WriteByte(sensor, SKIP_ROM);            // Skip ROM
+        WriteByte(sensor, CONVERT);             // Convert
+        while (ReadBit(sensor) == 0) {
+            // wait for conversion to complete
+        }
+        conversionInProgress = 0;       // led off
+    }
+}
+
+uint32_t GetTemperature() {
+    uint32_t result = 0;
+    if (Reset(sensor) != 0) {
+        inError();
+    } else {
+        ScratchPad_t scratchpad;
+        WriteByte(sensor, SKIP_ROM);    // Skip ROM
+        WriteByte(sensor, READ_SCRATCHPAD);    // Read Scrachpad
+        scratchpad.LSB = ReadByte(sensor);
+        scratchpad.MSB = ReadByte(sensor);
+        Reset(sensor);    // terminate read as we only want temperature
+        result = ((scratchpad.MSB << 8) | scratchpad.LSB);
+    }
+    return result;
+}
+
+ROM_Code_t ReadROM() {
+    ROM_Code_t ROM_Code;
+    if (Reset(sensor) != 0) {
+        inError();
+    } else {
+        
+        WriteByte(sensor, READ_ROM);    // Read ROM
+        for (uint32_t i = 0; i < 8; ++i) {
+            ROM_Code.rom[i] = ReadByte(sensor);
+        }
+    }
+    return ROM_Code;
+}
+
+// temperature is store as 7.4 fixed point format (assuming 12 bit conversion)
+void showTemperature(float *f) {
+    DoConversion();
+    uint32_t temp = GetTemperature();
+    *f = (temp & 0x0F) * 0.0625;    // calculate .4 part
+    *f += (temp >> 4);    // add 7.0 part to it
+    //return(f);
+    //s.printf("Temp is %2.1fC\n\r", f);    // display in 2.1 format
+}

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/ds1990.h	Fri Aug 23 08:36:59 2013 +0000
@@ -0,0 +1,20 @@
+#ifndef _DS1990_
+#define _DS1990_
+
+
+#include <stdint.h>
+#include "mbed.h"
+
+// Device Faimly ID and Setial number information
+typedef union {
+    uint8_t rom[8];
+    struct {
+        uint8_t    familyCode;
+        uint8_t    serialNo[8];
+        uint8_t    CRC;
+    } BYTES;
+} ROM_Code_t;
+
+ROM_Code_t ReadROM();
+
+#endif
\ No newline at end of file

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Fri Aug 23 08:36:59 2013 +0000
@@ -0,0 +1,23 @@
+#include "mbed.h"
+#include "ds1990.h"
+#include "DS1Wire.h"
+
+Serial pc(USBTX, USBRX);
+DigitalInOut sensor(p21);
+AnalogIn input(p18);
+
+
+
+int main(void){
+
+
+ROM_Code_t ROM_Code = ReadROM();
+
+
+pc.printf("Family code: 0x%X\n\r", ROM_Code.BYTES.familyCode);
+    pc.printf("Serial Number: ");
+    for (uint32_t i = 8; i != 0; --i) {
+        pc.printf("%02X%s", ROM_Code.BYTES.serialNo[i-1], (i != 1)?":":"\r\n");
+    }
+Reset();
+}

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mbed.bld	Fri Aug 23 08:36:59 2013 +0000
@@ -0,0 +1,1 @@
+http://mbed.org/users/mbed_official/code/mbed/builds/9c8f0e3462fb
\ No newline at end of file