Renato Loureiro / Mbed 2 deprecated 1_wire_ibutton

ibutton read with modified ds18b20 libraries

Dependencies:   mbed

Due to the lack of programs for ibutton interfacing with mbed, i built this one (still needs a lot of development), it's in a very basic state, but i'm working on it...

ds1990.cpp@0:4f399e4b64a9, 2013-08-23 (annotated)

Committer:
Renato
Date:
Fri Aug 23 08:36:59 2013 +0000
Revision:
0:4f399e4b64a9
Function to read ibutton serial & family

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Renato 0:4f399e4b64a9 1 #include "ds1990.h"
Renato 0:4f399e4b64a9 2 #include "DS1Wire.h"
Renato 0:4f399e4b64a9 3 #include "mbed.h"
Renato 0:4f399e4b64a9 4 #include <stdint.h>
Renato 0:4f399e4b64a9 5
Renato 0:4f399e4b64a9 6 // Device byte commands over 1-wire serial
Renato 0:4f399e4b64a9 7 enum COMMANDS { READ_ROM = 0x33, CONVERT = 0x44, READ_SCRATCHPAD = 0xBE, SKIP_ROM = 0xCC };
Renato 0:4f399e4b64a9 8
Renato 0:4f399e4b64a9 9
Renato 0:4f399e4b64a9 10 // device onboard register layout
Renato 0:4f399e4b64a9 11 typedef struct {
Renato 0:4f399e4b64a9 12 uint8_t LSB;
Renato 0:4f399e4b64a9 13 uint8_t MSB;
Renato 0:4f399e4b64a9 14 uint8_t Th;
Renato 0:4f399e4b64a9 15 uint8_t Tl;
Renato 0:4f399e4b64a9 16 uint8_t config;
Renato 0:4f399e4b64a9 17 uint8_t reserved0xFF;
Renato 0:4f399e4b64a9 18 uint8_t reserved0xCH;
Renato 0:4f399e4b64a9 19 uint8_t reserved0x10;
Renato 0:4f399e4b64a9 20 uint8_t CRC;
Renato 0:4f399e4b64a9 21 } ScratchPad_t;
Renato 0:4f399e4b64a9 22
Renato 0:4f399e4b64a9 23
Renato 0:4f399e4b64a9 24 DigitalOut conversionInProgress(LED4); // conversion in progress
Renato 0:4f399e4b64a9 25 DigitalOut resetFailure(LED1); // for error reporting
Renato 0:4f399e4b64a9 26 extern DigitalInOut sensor; // sensor pin
Renato 0:4f399e4b64a9 27
Renato 0:4f399e4b64a9 28 static void inError() {
Renato 0:4f399e4b64a9 29 while (1) {
Renato 0:4f399e4b64a9 30 resetFailure = !resetFailure;
Renato 0:4f399e4b64a9 31 wait(0.2);
Renato 0:4f399e4b64a9 32 }
Renato 0:4f399e4b64a9 33 }
Renato 0:4f399e4b64a9 34
Renato 0:4f399e4b64a9 35 void DoConversion() {
Renato 0:4f399e4b64a9 36 if (Reset(sensor) != 0) {
Renato 0:4f399e4b64a9 37 inError();
Renato 0:4f399e4b64a9 38 } else {
Renato 0:4f399e4b64a9 39 conversionInProgress = 1; // led on
Renato 0:4f399e4b64a9 40 WriteByte(sensor, SKIP_ROM); // Skip ROM
Renato 0:4f399e4b64a9 41 WriteByte(sensor, CONVERT); // Convert
Renato 0:4f399e4b64a9 42 while (ReadBit(sensor) == 0) {
Renato 0:4f399e4b64a9 43 // wait for conversion to complete
Renato 0:4f399e4b64a9 44 }
Renato 0:4f399e4b64a9 45 conversionInProgress = 0; // led off
Renato 0:4f399e4b64a9 46 }
Renato 0:4f399e4b64a9 47 }
Renato 0:4f399e4b64a9 48
Renato 0:4f399e4b64a9 49 uint32_t GetTemperature() {
Renato 0:4f399e4b64a9 50 uint32_t result = 0;
Renato 0:4f399e4b64a9 51 if (Reset(sensor) != 0) {
Renato 0:4f399e4b64a9 52 inError();
Renato 0:4f399e4b64a9 53 } else {
Renato 0:4f399e4b64a9 54 ScratchPad_t scratchpad;
Renato 0:4f399e4b64a9 55 WriteByte(sensor, SKIP_ROM); // Skip ROM
Renato 0:4f399e4b64a9 56 WriteByte(sensor, READ_SCRATCHPAD); // Read Scrachpad
Renato 0:4f399e4b64a9 57 scratchpad.LSB = ReadByte(sensor);
Renato 0:4f399e4b64a9 58 scratchpad.MSB = ReadByte(sensor);
Renato 0:4f399e4b64a9 59 Reset(sensor); // terminate read as we only want temperature
Renato 0:4f399e4b64a9 60 result = ((scratchpad.MSB << 8) | scratchpad.LSB);
Renato 0:4f399e4b64a9 61 }
Renato 0:4f399e4b64a9 62 return result;
Renato 0:4f399e4b64a9 63 }
Renato 0:4f399e4b64a9 64
Renato 0:4f399e4b64a9 65 ROM_Code_t ReadROM() {
Renato 0:4f399e4b64a9 66 ROM_Code_t ROM_Code;
Renato 0:4f399e4b64a9 67 if (Reset(sensor) != 0) {
Renato 0:4f399e4b64a9 68 inError();
Renato 0:4f399e4b64a9 69 } else {
Renato 0:4f399e4b64a9 70
Renato 0:4f399e4b64a9 71 WriteByte(sensor, READ_ROM); // Read ROM
Renato 0:4f399e4b64a9 72 for (uint32_t i = 0; i < 8; ++i) {
Renato 0:4f399e4b64a9 73 ROM_Code.rom[i] = ReadByte(sensor);
Renato 0:4f399e4b64a9 74 }
Renato 0:4f399e4b64a9 75 }
Renato 0:4f399e4b64a9 76 return ROM_Code;
Renato 0:4f399e4b64a9 77 }
Renato 0:4f399e4b64a9 78
Renato 0:4f399e4b64a9 79 // temperature is store as 7.4 fixed point format (assuming 12 bit conversion)
Renato 0:4f399e4b64a9 80 void showTemperature(float *f) {
Renato 0:4f399e4b64a9 81 DoConversion();
Renato 0:4f399e4b64a9 82 uint32_t temp = GetTemperature();
Renato 0:4f399e4b64a9 83 *f = (temp & 0x0F) * 0.0625; // calculate .4 part
Renato 0:4f399e4b64a9 84 *f += (temp >> 4); // add 7.0 part to it
Renato 0:4f399e4b64a9 85 //return(f);
Renato 0:4f399e4b64a9 86 //s.printf("Temp is %2.1fC\n\r", f); // display in 2.1 format
Renato 0:4f399e4b64a9 87 }