Rob Dobson / RdGasUseMonitor

Monitor for central heating system (e.g. 2zones+hw) Supports up to 15 temp probes (DS18B20/DS18S20) 3 valve monitors Gas pulse meter recording Use stand-alone or with nodeEnergyServer See http://robdobson.com/2015/09/central-heating-monitor

Dependencies:   EthernetInterfacePlusHostname NTPClient Onewire RdWebServer SDFileSystem-RTOS mbed-rtos mbed-src

PulsePin.cpp@5:5bccf48799d4, 2015-02-17 (annotated)

Committer:
Bobty
Date:
Tue Feb 17 21:33:39 2015 +0000
Revision:
5:5bccf48799d4
Parent:
4:0d3a207680b0
Child:
10:72eb217def1f
Tidied up - but is unstable - web server crashes after some time

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Bobty 2:6bfef0839102 1 // Handles a pin that has a slow pulse applied
Bobty 2:6bfef0839102 2 // Written for a gas meter monitor
Bobty 2:6bfef0839102 3
Bobty 2:6bfef0839102 4 #include "PulsePin.h"
Bobty 2:6bfef0839102 5
Bobty 4:0d3a207680b0 6 PulsePin::PulsePin(DigitalIn& pin, bool detectRisingEdge, int waitForPinStabilisationMs) :
Bobty 2:6bfef0839102 7 _pin(pin)
Bobty 2:6bfef0839102 8 {
Bobty 4:0d3a207680b0 9 _detectRisingEdge = detectRisingEdge;
Bobty 2:6bfef0839102 10 _waitForPinStabilisationMs = waitForPinStabilisationMs;
Bobty 2:6bfef0839102 11 _pinTimer.start();
Bobty 2:6bfef0839102 12 _curPinState = _pin;
Bobty 2:6bfef0839102 13 _lastStableTimeMs = _pinTimer.read_ms();
Bobty 2:6bfef0839102 14 _firstEdgeDetected = false;
Bobty 2:6bfef0839102 15 _timeBetweenEdgesMs = 0;
Bobty 5:5bccf48799d4 16 _pulseCount = 0;
Bobty 5:5bccf48799d4 17 _pinTimerMinutes = 0;
Bobty 2:6bfef0839102 18 }
Bobty 2:6bfef0839102 19
Bobty 2:6bfef0839102 20 bool PulsePin::Service()
Bobty 2:6bfef0839102 21 {
Bobty 2:6bfef0839102 22 // Check time since last edge - looking for stability
Bobty 2:6bfef0839102 23 int timeNowMs = _pinTimer.read_ms();
Bobty 5:5bccf48799d4 24
Bobty 5:5bccf48799d4 25 // Check if over 1 minute (as the timer wraps around after 30 mins)
Bobty 5:5bccf48799d4 26 if (timeNowMs > 60000)
Bobty 5:5bccf48799d4 27 {
Bobty 5:5bccf48799d4 28 _pinTimerMinutes++;
Bobty 5:5bccf48799d4 29 _pinTimer.reset();
Bobty 5:5bccf48799d4 30 timeNowMs -= 60000;
Bobty 5:5bccf48799d4 31 }
Bobty 5:5bccf48799d4 32
Bobty 5:5bccf48799d4 33 // Get the real time elapsed (still wraps but now only after about 500 hours)
Bobty 5:5bccf48799d4 34 timeNowMs = _pinTimerMinutes*60000 + timeNowMs;
Bobty 5:5bccf48799d4 35
Bobty 5:5bccf48799d4 36 // Check for pin stabilization
Bobty 2:6bfef0839102 37 if (timeNowMs < _lastStableTimeMs + _waitForPinStabilisationMs)
Bobty 2:6bfef0839102 38 return false;
Bobty 2:6bfef0839102 39
Bobty 2:6bfef0839102 40 // Check for a change of state
Bobty 2:6bfef0839102 41 bool pinState = _pin;
Bobty 2:6bfef0839102 42 if (pinState == _curPinState)
Bobty 2:6bfef0839102 43 return false;
Bobty 2:6bfef0839102 44
Bobty 2:6bfef0839102 45 _curPinState = pinState;
Bobty 2:6bfef0839102 46 _lastStableTimeMs = timeNowMs;
Bobty 2:6bfef0839102 47
Bobty 2:6bfef0839102 48 // Check if this is the direction of edge we're looking for
Bobty 4:0d3a207680b0 49 if (pinState != _detectRisingEdge)
Bobty 2:6bfef0839102 50 return false;
Bobty 2:6bfef0839102 51
Bobty 2:6bfef0839102 52 // Reset the timer to avoid wrap around problems
Bobty 2:6bfef0839102 53 bool firstEdgeDetected = _firstEdgeDetected;
Bobty 5:5bccf48799d4 54 _pinTimerMinutes = 0;
Bobty 2:6bfef0839102 55 _pinTimer.reset();
Bobty 2:6bfef0839102 56 _firstEdgeDetected = true;
Bobty 2:6bfef0839102 57 _lastStableTimeMs = 0;
Bobty 2:6bfef0839102 58
Bobty 2:6bfef0839102 59 // Check if this should be returned
Bobty 2:6bfef0839102 60 if (!firstEdgeDetected)
Bobty 2:6bfef0839102 61 return false;
Bobty 2:6bfef0839102 62 _timeBetweenEdgesMs = timeNowMs;
Bobty 5:5bccf48799d4 63 _pulseCount++;
Bobty 2:6bfef0839102 64 return true;
Bobty 2:6bfef0839102 65 }
Bobty 2:6bfef0839102 66
Bobty 5:5bccf48799d4 67 int PulsePin::GetPulseRateMs()
Bobty 2:6bfef0839102 68 {
Bobty 2:6bfef0839102 69 return _timeBetweenEdgesMs;
Bobty 2:6bfef0839102 70 }
Bobty 5:5bccf48799d4 71
Bobty 5:5bccf48799d4 72 int PulsePin::GetPulseCount()
Bobty 5:5bccf48799d4 73 {
Bobty 5:5bccf48799d4 74 return _pulseCount;
Bobty 5:5bccf48799d4 75 }
Bobty 5:5bccf48799d4 76
Bobty 5:5bccf48799d4 77 void PulsePin::SetPulseCount(int pulseCount)
Bobty 5:5bccf48799d4 78 {
Bobty 5:5bccf48799d4 79 _pulseCount = pulseCount;
Bobty 5:5bccf48799d4 80 }