More reworking
- Added ability to add heating profile - waitForReady now takes a variable timeout value - Added ability to change the sample accuracy
This commit is contained in:
npotts
Ron Evans
parent
b1825f2e90
commit
1d6b33a351
|
|
@ -1,5 +1,5 @@
|
|||
/*
|
||||
* Copyright (c) 2018 Nicholas Potts <nick@the-potts.com>
|
||||
* Copyright (c) 2016-2017 Weston Schmidt <weston_schmidt@alumni.purdue.edu>
|
||||
*
|
||||
* Licensed under the Apache License, Version 2.0 (the "License");
|
||||
* you may not use this file except in compliance with the License.
|
||||
|
|
@ -18,8 +18,8 @@ package i2c
|
|||
|
||||
// TH02Driver is a driver for the TH02-D based devices.
|
||||
//
|
||||
// This module was tested with a Grove Temperature and Humidty Sensor (High Accuracy)
|
||||
// https://www.seeedstudio.com/Grove-Temperature-Humidity-Sensor-High-Accuracy-Min-p-1921.html
|
||||
// This module was tested with AdaFruit Sensiron SHT32-D Breakout.
|
||||
// https://www.adafruit.com/products/2857
|
||||
|
||||
import (
|
||||
"fmt"
|
||||
|
|
@ -28,17 +28,31 @@ import (
|
|||
"gobot.io/x/gobot"
|
||||
)
|
||||
|
||||
// TH02Address is the default address of device
|
||||
const TH02Address = 0x40
|
||||
const (
|
||||
|
||||
//TH02ConfigReg is the configuration register
|
||||
const TH02ConfigReg = 0x03
|
||||
// TH02AddressA is the default address of device
|
||||
TH02Address = 0x40
|
||||
|
||||
// TH02HighAccuracyTemp is the CONFIG write value to start reading temperature
|
||||
const TH02HighAccuracyTemp = 0x11
|
||||
//TH02ConfigReg is the configuration register
|
||||
TH02ConfigReg = 0x03
|
||||
|
||||
//TH02HighAccuracyRH is the CONFIG write value to start reading high accuracy RH
|
||||
const TH02HighAccuracyRH = 0x01
|
||||
// TH02RegConfigHighAccuracyTemp is the CONFIG register to read temperature
|
||||
// TH02HighAccuracyTemp = 0x11
|
||||
|
||||
//TH02RegConfigHighAccuracyRH is the CONFIG register to read high accuracy RH
|
||||
// TH02HighAccuracyRH = 0x01
|
||||
)
|
||||
|
||||
const (
|
||||
TH02HighAccuracy = 0 //High Accuracy
|
||||
TH02LowAccuracy = 1 //Lower Accuracy
|
||||
)
|
||||
|
||||
var (
|
||||
//ErrInvalidAccuracy = errors.New("Invalid accuracy")
|
||||
//ErrInvalidCrc = errors.New("Invalid crc")
|
||||
//ErrInvalidTemp = errors.New("Invalid temperature units")
|
||||
)
|
||||
|
||||
// TH02Driver is a Driver for a TH02 humidity and temperature sensor
|
||||
type TH02Driver struct {
|
||||
|
|
@ -49,10 +63,15 @@ type TH02Driver struct {
|
|||
Config
|
||||
addr byte
|
||||
accuracy byte
|
||||
heating bool
|
||||
|
||||
delay time.Duration
|
||||
}
|
||||
|
||||
// NewTH02Driver creates a new driver with specified i2c interface
|
||||
// NewTH02Driver creates a new driver with specified i2c interface.
|
||||
// Defaults to:
|
||||
// - Using high accuracy (lower speed) measurements cycles.
|
||||
// - Emitting values in "C". If you want F, set Units to "F"
|
||||
// Params:
|
||||
// conn Connector - the Adaptor to use with this Driver
|
||||
//
|
||||
|
|
@ -67,8 +86,10 @@ func NewTH02Driver(a Connector, options ...func(Config)) *TH02Driver {
|
|||
connector: a,
|
||||
addr: TH02Address,
|
||||
Config: NewConfig(),
|
||||
heating: false,
|
||||
}
|
||||
// s.SetAccuracy(TH02AccuracyHigh)
|
||||
|
||||
s.SetAccuracy(1)
|
||||
|
||||
for _, option := range options {
|
||||
option(s)
|
||||
|
|
@ -101,50 +122,77 @@ func (s *TH02Driver) Halt() (err error) { return }
|
|||
// SetAddress sets the address of the device
|
||||
func (s *TH02Driver) SetAddress(address int) { s.addr = byte(address) }
|
||||
|
||||
// Accuracy returns the accuracy of the sampling
|
||||
func (s *TH02Driver) Accuracy() byte { return s.accuracy }
|
||||
|
||||
// SetAccuracy sets the accuracy of the sampling. It will only be used on the next
|
||||
// measurment request. Invalid value will use the default of High
|
||||
func (s *TH02Driver) SetAccuracy(a byte) {
|
||||
if a == TH02LowAccuracy {
|
||||
s.accuracy = a
|
||||
} else {
|
||||
s.accuracy = TH02HighAccuracy
|
||||
}
|
||||
}
|
||||
|
||||
// SerialNumber returns the serial number of the chip
|
||||
func (s *TH02Driver) SerialNumber() (sn uint32, err error) {
|
||||
ret, err := s.readRegister(0x11)
|
||||
return uint32(ret) >> 4, err
|
||||
}
|
||||
|
||||
// Heater returns true if the heater is enabled
|
||||
func (s *TH02Driver) Heater() (status bool, err error) {
|
||||
st, err := s.readRegister(0x11)
|
||||
return (0x02 & st) == 0x02, err
|
||||
}
|
||||
|
||||
func (s *TH02Driver) applysettings(base byte) byte {
|
||||
if s.accuracy == TH02LowAccuracy {
|
||||
base = base & 0xd5
|
||||
} else {
|
||||
base = base | 0x20
|
||||
}
|
||||
if s.heating {
|
||||
base = base & 0xfd
|
||||
} else {
|
||||
base = base | 0x02
|
||||
}
|
||||
base = base | 0x01 //set the "sample" bit
|
||||
return base
|
||||
}
|
||||
|
||||
// Sample returns the temperature in celsius and relative humidity for one sample
|
||||
func (s *TH02Driver) Sample() (temp float32, rh float32, err error) {
|
||||
if err := s.writeRegister(TH02ConfigReg, TH02HighAccuracyRH); err != nil {
|
||||
func (s *TH02Driver) Sample() (temperature float32, relhumidity float32, _ error) {
|
||||
|
||||
if err := s.writeRegister(TH02ConfigReg, s.applysettings(0x10)); err != nil {
|
||||
return 0, 0, err
|
||||
}
|
||||
|
||||
rrh, err := s.readData()
|
||||
rawrh, err := s.readData()
|
||||
if err != nil {
|
||||
return 0, 0, err
|
||||
}
|
||||
rrh = rrh >> 4
|
||||
rh = float32(rrh)/16.0 - 24.0
|
||||
relhumidity = float32(rawrh>>4)/16.0 - 24.0
|
||||
|
||||
if err := s.writeRegister(TH02ConfigReg, TH02HighAccuracyTemp); err != nil {
|
||||
return 0, 0, err
|
||||
if err := s.writeRegister(TH02ConfigReg, s.applysettings(0x00)); err != nil {
|
||||
return 0, relhumidity, err
|
||||
}
|
||||
|
||||
rt, err := s.readData()
|
||||
rawt, err := s.readData()
|
||||
if err != nil {
|
||||
return 0, rh, err
|
||||
return 0, relhumidity, err
|
||||
}
|
||||
rt = rt / 4
|
||||
temp = float32(rt)/32.0 - 50.0
|
||||
temperature = float32(rawt>>2)/32.0 - 50.0
|
||||
|
||||
switch s.Units {
|
||||
case "F":
|
||||
temp = 9.0/5.0 + 32.0
|
||||
temperature = 9.0/5.0*temperature + 32.0
|
||||
}
|
||||
|
||||
return temp, rh, nil
|
||||
return temperature, relhumidity, nil
|
||||
|
||||
}
|
||||
|
||||
// getStatusRegister returns the device status register
|
||||
func (s *TH02Driver) getStatusRegister() (status byte, err error) {
|
||||
return s.readRegister(TH02ConfigReg)
|
||||
}
|
||||
|
||||
//writeRegister writes the value to the register.
|
||||
func (s *TH02Driver) writeRegister(reg, value byte) error {
|
||||
_, err := s.connection.Write([]byte{reg, value})
|
||||
|
|
@ -161,22 +209,33 @@ func (s *TH02Driver) readRegister(reg byte) (byte, error) {
|
|||
return rcvd[0], err
|
||||
}
|
||||
|
||||
func (s *TH02Driver) waitForReady() error {
|
||||
/*waitForReady blocks for up to the passed duration (which defaults to 50mS if nil)
|
||||
until the ~RDY bit is cleared, meanign a sample has been fully sampled and is ready for reading.
|
||||
|
||||
This is greedy.
|
||||
*/
|
||||
func (s *TH02Driver) waitForReady(dur *time.Duration) error {
|
||||
wait := 100 * time.Millisecond
|
||||
if dur != nil {
|
||||
wait = *dur
|
||||
}
|
||||
start := time.Now()
|
||||
for {
|
||||
if time.Since(start) > 100*time.Millisecond {
|
||||
if time.Since(start) > wait {
|
||||
return fmt.Errorf("timeout on \\RDY")
|
||||
}
|
||||
reg, _ := s.readRegister(0x00)
|
||||
if reg == 0 {
|
||||
|
||||
//yes, i am eating the error.
|
||||
if reg, _ := s.readRegister(0x00); reg == 0 {
|
||||
return nil
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/*readData fetches the data from the data 'registers'*/
|
||||
func (s *TH02Driver) readData() (uint16, error) {
|
||||
if err := s.waitForReady(); err != nil {
|
||||
return 1, err
|
||||
if err := s.waitForReady(nil); err != nil {
|
||||
return 0, err
|
||||
}
|
||||
|
||||
if n, err := s.connection.Write([]byte{0x01}); err != nil || n != 1 {
|
||||
|
|
|
|||
Loading…
Reference in New Issue