Rob Meades / WaterMeterSupport

Support library for reading the Kamstrup FlowIQ2000 water meter via its serial interface.

This library provides support for reading a Kamstrup FlowIQ2000 water meter's serial interface. Interfacing to the meter from the C027 board requires a small interface circuit (note that this diagram also includes a water pump control circuit, which is needed by the IotMessage library):

/media/uploads/RobMeades/c027n_interface.png

This library is intended for use with the WaterMeterDemo project.

WaterMeterApi.hpp@0:0730cba56168, 2015-05-22 (annotated)

Committer:
RobMeades
Date:
Fri May 22 11:40:35 2015 +0000
Revision:
0:0730cba56168
Initial commit of FlowIQ2000 water meter support to mbed cloud.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
RobMeades 0:0730cba56168 1 /* Water Meter HW driver for Water Meter Demo
RobMeades 0:0730cba56168 2 *
RobMeades 0:0730cba56168 3 * Copyright (C) u-blox Melbourn Ltd
RobMeades 0:0730cba56168 4 * u-blox Melbourn Ltd, Melbourn, UK
RobMeades 0:0730cba56168 5 *
RobMeades 0:0730cba56168 6 * All rights reserved.
RobMeades 0:0730cba56168 7 *
RobMeades 0:0730cba56168 8 * This source file is the sole property of u-blox Melbourn Ltd.
RobMeades 0:0730cba56168 9 * Reproduction or utilization of this source in whole or part is
RobMeades 0:0730cba56168 10 * forbidden without the written consent of u-blox Melbourn Ltd.
RobMeades 0:0730cba56168 11 */
RobMeades 0:0730cba56168 12
RobMeades 0:0730cba56168 13 #ifndef WATER_METER_API_HPP
RobMeades 0:0730cba56168 14 #define WATER_METER_API_HPP
RobMeades 0:0730cba56168 15
RobMeades 0:0730cba56168 16 /**
RobMeades 0:0730cba56168 17 * @file water_meter_api.h
RobMeades 0:0730cba56168 18 * This file defines the API to the water meter HW
RobMeades 0:0730cba56168 19 * for the MWC demo 2015.
RobMeades 0:0730cba56168 20 */
RobMeades 0:0730cba56168 21
RobMeades 0:0730cba56168 22 // ----------------------------------------------------------------
RobMeades 0:0730cba56168 23 // HARDWARE
RobMeades 0:0730cba56168 24 // The code in this library is setup to expect a FlowIQ2100 water
RobMeades 0:0730cba56168 25 // meter to be connected through this circuit:
RobMeades 0:0730cba56168 26 //
RobMeades 0:0730cba56168 27 // C027N board Water Meter
RobMeades 0:0730cba56168 28 //
RobMeades 0:0730cba56168 29 // 5V o-------------------o-------------o------o Red (pwr/clk)
RobMeades 0:0730cba56168 30 // | |
RobMeades 0:0730cba56168 31 // | |
RobMeades 0:0730cba56168 32 // | |
RobMeades 0:0730cba56168 33 // | |
RobMeades 0:0730cba56168 34 // | |
RobMeades 0:0730cba56168 35 // | |
RobMeades 0:0730cba56168 36 // | |
RobMeades 0:0730cba56168 37 // | | |
RobMeades 0:0730cba56168 38 // | | 10k Ohm |
RobMeades 0:0730cba56168 39 // | | |
RobMeades 0:0730cba56168 40 // | |
RobMeades 0:0730cba56168 41 // 1k Ohm o-------------|------o Black (gnd)
RobMeades 0:0730cba56168 42 // ____ / |
RobMeades 0:0730cba56168 43 // D4 o--|____|--------| (transistor) |
RobMeades 0:0730cba56168 44 // _\/ |
RobMeades 0:0730cba56168 45 // | | |
RobMeades 0:0730cba56168 46 // | | | 10k Ohm
RobMeades 0:0730cba56168 47 // | | |
RobMeades 0:0730cba56168 48 // | |
RobMeades 0:0730cba56168 49 // D2 o--------------------------------o------o Green (data)
RobMeades 0:0730cba56168 50 // |
RobMeades 0:0730cba56168 51 // |
RobMeades 0:0730cba56168 52 // Gnd o------------------o
RobMeades 0:0730cba56168 53 //
RobMeades 0:0730cba56168 54 // ----------------------------------------------------------------
RobMeades 0:0730cba56168 55
RobMeades 0:0730cba56168 56 // ----------------------------------------------------------------
RobMeades 0:0730cba56168 57 // GENERAL COMPILE-TIME CONSTANTS
RobMeades 0:0730cba56168 58 // ----------------------------------------------------------------
RobMeades 0:0730cba56168 59
RobMeades 0:0730cba56168 60 // ----------------------------------------------------------------
RobMeades 0:0730cba56168 61 // CLASSES
RobMeades 0:0730cba56168 62 // ----------------------------------------------------------------
RobMeades 0:0730cba56168 63
RobMeades 0:0730cba56168 64 class WaterMeterHandler {
RobMeades 0:0730cba56168 65 public:
RobMeades 0:0730cba56168 66 /// Constructor.
RobMeades 0:0730cba56168 67 WaterMeterHandler (void);
RobMeades 0:0730cba56168 68 /// Destructor.
RobMeades 0:0730cba56168 69 ~WaterMeterHandler(void);
RobMeades 0:0730cba56168 70 /// Initialise the water meter, ensuring that there
RobMeades 0:0730cba56168 71 // is an electrical connection and that at least
RobMeades 0:0730cba56168 72 // a single character can be correctly received from
RobMeades 0:0730cba56168 73 // it (by checking parity).
RobMeades 0:0730cba56168 74 // \param data pin to use for receiving data on the
RobMeades 0:0730cba56168 75 // C027N board.
RobMeades 0:0730cba56168 76 // \param pwrClk pin to use to send pwr/clk on the
RobMeades 0:0730cba56168 77 // C027N board.
RobMeades 0:0730cba56168 78 // \param clkRateHz the clock rate to use when
RobMeades 0:0730cba56168 79 // reading out data bits.
RobMeades 0:0730cba56168 80 // \return true if successful, otherwise false.
RobMeades 0:0730cba56168 81 bool init (PinName dataPin = D2, PinName pwrClkPin = D4, uint32_t clkRateHz = 1000);
RobMeades 0:0730cba56168 82
RobMeades 0:0730cba56168 83 /// Take a water volume reading from the meter.
RobMeades 0:0730cba56168 84 // \param a pointer to somewhere to put the reading.
RobMeades 0:0730cba56168 85 // Only written-to if the outcome is true. May be NULL,
RobMeades 0:0730cba56168 86 // in which case the success check is still carried out.
RobMeades 0:0730cba56168 87 // \\return success if true, otherwise false.
RobMeades 0:0730cba56168 88 bool readLitres (uint32_t * pValue);
RobMeades 0:0730cba56168 89
RobMeades 0:0730cba56168 90 /// Read the serial number from the meter.
RobMeades 0:0730cba56168 91 // \param a pointer to somewhere to put the serial number.
RobMeades 0:0730cba56168 92 // Only written-to if the outcome is true. May be NULL,
RobMeades 0:0730cba56168 93 // in which case the success check is still carried out.
RobMeades 0:0730cba56168 94 // \\return success if true, otherwise false.
RobMeades 0:0730cba56168 95 bool readSerialNumber (uint32_t * pValue);
RobMeades 0:0730cba56168 96
RobMeades 0:0730cba56168 97 /// Set debug to bool.
RobMeades 0:0730cba56168 98 // \param onNotOff debug will come out if this is true.
RobMeades 0:0730cba56168 99 // Default is no debug.
RobMeades 0:0730cba56168 100 void setDebugOn (bool onNotOff);
RobMeades 0:0730cba56168 101
RobMeades 0:0730cba56168 102 private:
RobMeades 0:0730cba56168 103 /// Set this to true once initialised.
RobMeades 0:0730cba56168 104 bool ready;
RobMeades 0:0730cba56168 105 /// Set this to true for debug.
RobMeades 0:0730cba56168 106 bool debug;
RobMeades 0:0730cba56168 107 /// The pin on the C027N board to use for data reception
RobMeades 0:0730cba56168 108 // from the meter.
RobMeades 0:0730cba56168 109 DigitalIn *pData;
RobMeades 0:0730cba56168 110 /// The pin on the C027N board to use for pwr/clock to
RobMeades 0:0730cba56168 111 // the meter.
RobMeades 0:0730cba56168 112 DigitalOut *pPwrClk;
RobMeades 0:0730cba56168 113 /// The length of half a clock period in microseconds to
RobMeades 0:0730cba56168 114 // use when reading data off the water meter.
RobMeades 0:0730cba56168 115 uint32_t halfClkPeriodUs;
RobMeades 0:0730cba56168 116 /// Power on the meter (by toggling the pwrClk line until
RobMeades 0:0730cba56168 117 // the data line goes low).
RobMeades 0:0730cba56168 118 // \return true if successful, otherwise false.
RobMeades 0:0730cba56168 119 bool pwrOn (void);
RobMeades 0:0730cba56168 120 /// Power off the meter (by setting the pwrClk line low).
RobMeades 0:0730cba56168 121 void pwrOff (void);
RobMeades 0:0730cba56168 122 /// Read a start bit from the meter.
RobMeades 0:0730cba56168 123 // \return true if successful, otherwise false.
RobMeades 0:0730cba56168 124 bool readStartBit (void);
RobMeades 0:0730cba56168 125 /// Read a stop bit from the meter.
RobMeades 0:0730cba56168 126 // \return true if successful, otherwise false.
RobMeades 0:0730cba56168 127 bool readStopBit (void);
RobMeades 0:0730cba56168 128 /// Toggle the pwrClk line to read a data bit from the water
RobMeades 0:0730cba56168 129 // meter.
RobMeades 0:0730cba56168 130 // \return true if a 1 is read, false if a 0 is read.
RobMeades 0:0730cba56168 131 bool readDataBit (void);
RobMeades 0:0730cba56168 132 /// Check that parity is good
RobMeades 0:0730cba56168 133 // \return true if successful, otherwise false.
RobMeades 0:0730cba56168 134 bool parityIsGood (uint8_t numOnes);
RobMeades 0:0730cba56168 135 /// Read a character from the meter and check parity.
RobMeades 0:0730cba56168 136 // \param pChar a pointer to a location where the received
RobMeades 0:0730cba56168 137 // character can be stored. Only filled in if the read is
RobMeades 0:0730cba56168 138 // successful. May be NULL, in which case the parity check
RobMeades 0:0730cba56168 139 // is still carried out.
RobMeades 0:0730cba56168 140 // \return true if successful, otherwise false.
RobMeades 0:0730cba56168 141 bool readChar (char *pChar);
RobMeades 0:0730cba56168 142 /// Read a whole fixed-length message from the water meter.
RobMeades 0:0730cba56168 143 // Reading stops when a parity error occurs or when the
RobMeades 0:0730cba56168 144 // requested number of bytes has been read.
RobMeades 0:0730cba56168 145 // \param pChars a pointer to a location where the received
RobMeades 0:0730cba56168 146 // data bytes can be stored. Must be at least numBytes big.
RobMeades 0:0730cba56168 147 // \return the number of bytes read.
RobMeades 0:0730cba56168 148 // \param numChars the number of bytes to read.
RobMeades 0:0730cba56168 149 uint32_t readFixedLengthMsg (char *pChars, uint32_t numChars);
RobMeades 0:0730cba56168 150 /// Convert a number of characters representing a decimal
RobMeades 0:0730cba56168 151 // value into a uint32_t value.
RobMeades 0:0730cba56168 152 // Characters are assumed to be ASCII, single byte values.
RobMeades 0:0730cba56168 153 // If a non-numeric character (including a decimal point)
RobMeades 0:0730cba56168 154 // is found then fail is returned.
RobMeades 0:0730cba56168 155 // \param pChars a pointer to the start of the character array.
RobMeades 0:0730cba56168 156 // \param numChars the number of characters.
RobMeades 0:0730cba56168 157 // \param pValue the uint32_t value, only written-to if
RobMeades 0:0730cba56168 158 // success is returned. May be NULL in which case the success
RobMeades 0:0730cba56168 159 // check is still carried out.
RobMeades 0:0730cba56168 160 // \return true if successful, otherwise false.
RobMeades 0:0730cba56168 161 bool decCharsToUint32 (char * pChars, uint32_t numChars, uint32_t * pValue);
RobMeades 0:0730cba56168 162 };
RobMeades 0:0730cba56168 163
RobMeades 0:0730cba56168 164 #endif
RobMeades 0:0730cba56168 165
RobMeades 0:0730cba56168 166 // End Of File