Stephen McGarry
/
SHT_v1
SHT.h@0:df1c8f2961a1, 2010-01-24 (annotated)
- Committer:
- roselea
- Date:
- Sun Jan 24 22:00:35 2010 +0000
- Revision:
- 0:df1c8f2961a1
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
roselea | 0:df1c8f2961a1 | 1 | /* mbed module to use a Sensirion SHT1x /SHT7x sensor |
roselea | 0:df1c8f2961a1 | 2 | * Copyright (c) 2007-2009 Stephen McGarry |
roselea | 0:df1c8f2961a1 | 3 | * Released under the MIT License: http://mbed.org/license/mit |
roselea | 0:df1c8f2961a1 | 4 | */ |
roselea | 0:df1c8f2961a1 | 5 | #ifndef SHT_H |
roselea | 0:df1c8f2961a1 | 6 | #define SHT_H |
roselea | 0:df1c8f2961a1 | 7 | |
roselea | 0:df1c8f2961a1 | 8 | #include "mbed.h" |
roselea | 0:df1c8f2961a1 | 9 | |
roselea | 0:df1c8f2961a1 | 10 | enum SHT_acc { |
roselea | 0:df1c8f2961a1 | 11 | SHT_low=0, |
roselea | 0:df1c8f2961a1 | 12 | SHT_high=1 |
roselea | 0:df1c8f2961a1 | 13 | }; |
roselea | 0:df1c8f2961a1 | 14 | |
roselea | 0:df1c8f2961a1 | 15 | typedef unsigned char byte; |
roselea | 0:df1c8f2961a1 | 16 | |
roselea | 0:df1c8f2961a1 | 17 | class SHT : public Base { |
roselea | 0:df1c8f2961a1 | 18 | public: |
roselea | 0:df1c8f2961a1 | 19 | /* Constructor: SHT |
roselea | 0:df1c8f2961a1 | 20 | * Creates an SHT interface connected to specific pins. |
roselea | 0:df1c8f2961a1 | 21 | * |
roselea | 0:df1c8f2961a1 | 22 | */ |
roselea | 0:df1c8f2961a1 | 23 | SHT(PinName p_sclk, PinName p_data, SHT_acc p_accuracy); |
roselea | 0:df1c8f2961a1 | 24 | |
roselea | 0:df1c8f2961a1 | 25 | /* Functions |
roselea | 0:df1c8f2961a1 | 26 | */ |
roselea | 0:df1c8f2961a1 | 27 | float get_temperature(); // get the most recent temp reading |
roselea | 0:df1c8f2961a1 | 28 | float get_humidity(); // get the most recent humidity reading |
roselea | 0:df1c8f2961a1 | 29 | float get_dewpoint(); // get the most recent dewpoint value |
roselea | 0:df1c8f2961a1 | 30 | void update(SHT_acc accuracy); // update stored values from sensor |
roselea | 0:df1c8f2961a1 | 31 | |
roselea | 0:df1c8f2961a1 | 32 | protected: |
roselea | 0:df1c8f2961a1 | 33 | byte read_byte(bool send_ack); |
roselea | 0:df1c8f2961a1 | 34 | char write_byte(byte value); |
roselea | 0:df1c8f2961a1 | 35 | void trans_start(void); |
roselea | 0:df1c8f2961a1 | 36 | void connection_reset(void); |
roselea | 0:df1c8f2961a1 | 37 | char soft_reset(); |
roselea | 0:df1c8f2961a1 | 38 | char read_status(byte &value); |
roselea | 0:df1c8f2961a1 | 39 | char write_status(byte value); |
roselea | 0:df1c8f2961a1 | 40 | char measure(int &value, byte mode); |
roselea | 0:df1c8f2961a1 | 41 | void calculate(); |
roselea | 0:df1c8f2961a1 | 42 | |
roselea | 0:df1c8f2961a1 | 43 | DigitalOut sclk; |
roselea | 0:df1c8f2961a1 | 44 | DigitalInOut data; |
roselea | 0:df1c8f2961a1 | 45 | SHT_acc accuracy; // will we use high or low accuracy mode on the sensor |
roselea | 0:df1c8f2961a1 | 46 | |
roselea | 0:df1c8f2961a1 | 47 | float temperature; // calculated from sensor reading |
roselea | 0:df1c8f2961a1 | 48 | float humidity; |
roselea | 0:df1c8f2961a1 | 49 | float dewpoint; |
roselea | 0:df1c8f2961a1 | 50 | int temp,hum; // integer values from sensor before conversion |
roselea | 0:df1c8f2961a1 | 51 | |
roselea | 0:df1c8f2961a1 | 52 | enum commands { |
roselea | 0:df1c8f2961a1 | 53 | com_read_status_reg=0x06, |
roselea | 0:df1c8f2961a1 | 54 | com_write_status_reg=0x07, |
roselea | 0:df1c8f2961a1 | 55 | com_measure_temp=0x03, |
roselea | 0:df1c8f2961a1 | 56 | com_measure_humid=0x05, |
roselea | 0:df1c8f2961a1 | 57 | com_reset=0x1E |
roselea | 0:df1c8f2961a1 | 58 | }; |
roselea | 0:df1c8f2961a1 | 59 | |
roselea | 0:df1c8f2961a1 | 60 | enum acks { |
roselea | 0:df1c8f2961a1 | 61 | no_ack=0, |
roselea | 0:df1c8f2961a1 | 62 | send_ack=1 |
roselea | 0:df1c8f2961a1 | 63 | }; |
roselea | 0:df1c8f2961a1 | 64 | }; |
roselea | 0:df1c8f2961a1 | 65 | |
roselea | 0:df1c8f2961a1 | 66 | #endif |