Arduino library for interfacing with EE893 CO2 sensor and other E2 interface devices
To use the EE893 library:
- Copy the EE893 directory into your Arduino libraries directory (%USERPROFILE%\Documents\Arduino\libraries)
- Include the library at the top of your sketch, and create a variable to refer to it:
#include <EE893.h>
EE893 Sensor;- Call the library functions to read values from the sensor:
Serial.print("CO2 Reading (Instantaneous):\t");
Serial.print(Sensor.readCo2Fast());
Serial.println("ppm");
//"CO2 Reading (Instantaneous): 1444ppm"Reads the current instantaneous CO2 measurement.
This function has 2 variants:
uint16_t readCo2Fast()Returns an integer containing the current instantaneous CO2 reading in ppm (parts per million).
If an error occurred, returns 0xFFFF.
byte readCo2Fast(byte *hi, byte *lo)On success, writes the high byte of the value into hi, and the low byte into lo.
Return values:
- 0: Success
- 1: Checksum failure while reading value
- 2: No response from device
Reads the recent average CO2 measurement.
This function has 2 variants:
uint16_t readCo2Accurate()Returns an integer containing the recent average CO2 reading in ppm (parts per million).
If an error occurred, returns 0xFFFF.
byte readCo2Accurate(byte *hi, byte *lo)On success, writes the high byte of the value into hi, and the low byte into lo.
Return values:
- 0: Success
- 1: Checksum failure while reading value
- 2: No response from device
Reads a single byte value from the device.
The value to returned is specified by passing one of the Control Byte names.
byte readByte(byte control_byte, byte *result)On success, writes the high byte of the value into hi, and the low byte into lo.
Return values:
- 0: Success
- 1: Checksum failure while reading value
- 2: No response from device
Reads a 16-bit value from the device.
The value to returned is specified by passing one of the Readable Value names.
byte readValue(byte get_value, uint16_t *result)On success, writes the value into result.
Return values:
- 0: Success
- 1: Checksum failure while reading value
- 2: No response from device
Reads a single byte from the Custom Memory area of the device.
Use this function to read configuration values from the device.
This function has 2 variants:
byte readByteFromAddress(byte address)Returns the byte from the custom memory address passed.
If an error occurred, returns 0xFF.
If the device does not support the value requested, returns 0xFF or 0x55.
byte readByteFromAddress(byte address, byte *result)On success, writes the byte from the custom memory address passed into result.
If the device does not support the value requested, result will be 0xFF or 0x55.
Return values:
- 0: Success
- 1: Checksum failure while reading value
- 2: No response from device
Reads a series of consecutive bytes from the Custom Memory area of the device.
Use this function to read information such as the device name or serial number.
byte readByteFromAddress(byte address, byte result[], byte length)On success, writes length consecutive bytes starting from the custom memory address passed into result.
If the device does not support one or more values requested, result will contain 0xFF or 0x55.
Return values:
- 0: Success
- 1: Checksum failure while reading values
- 2: No response from device
Reads the entire Custom Memory area of the device into a buffer.
byte dumpMemory(byte data[])On success, writes all 256 bytes of custom memory into data.
If the device does not support one or more values requested, result will contain 0xFF or 0x55.
Return values:
- 0: Success
- 1: Checksum failure while reading values
- 2: No response from device
Prints information about the device to the serial console (if connected).
void printSensorInfo()Example:
Sensor Type:
EE893
Sensor Sub-Type:
EE893-0 FT9
Custom Part Name:
EE893
Serial Number:
123456789123456
Bus Address:
0
Available Physical Measurements:
Humidity: Not Supported
Temperature: Not Supported
Air Velocity: Not Supported
CO2: Available
Status Byte:
Humidity: Error
Temperature: Error
Air Velocity: Error
CO2: OK
Checks the Available Physical Measurements flags, then prints all available measurements to the serial console (if connected).
void printAllValues()Example:
CO2 (Fast): 1030ppm
CO2 (Accurate): 688ppm
Reads the entire Custom Memory area of the device and prints it to the serial console (if connected).
void printAllValues()Example
Memory Dump:
0 1 2 3 4 5 6 7 8 9 A B C D E F
0 0x1 0x0 0x4 0x8 0x8 0x1 0x8 0x93 0x0 0x0 0x55 0x55 0x55 0x55 0x55 0x55
1 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55
2 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55
3 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55
4 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55
5 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x0 0x0 0x0 0x80 0x0 0x0 0x88 0x13
6 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55
7 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55
8 0xFF 0xFF 0xFF 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0xFF 0xFF 0xFF 0x55
9 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55
A 0x31 0x34 0x31 0x31 0x39 0x33 0x35 0x38 0x31 0x32 0x32 0x37 0x38 0x36 0x0 0x0
B 0x45 0x45 0x38 0x39 0x33 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0
C 0x0 0xCA 0x55 0x55 0x55 0x55 0xA0 0x8C 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55
D 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55
E 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55
F 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x55 0x9 0xB1
These readable value names are used to specify which value to return from the readValue() function:
#define HUMIDITY_VALUE 0x00
#define TEMPERATURE_VALUE 0x01
#define AIR_VELOCITY_VALUE 0x02
#define CO2_AVG_VALUE 0x02
#define CO2_VALUE 0x03These control byte names are used to specify which value to return from the readByte() function:
#define SENSOR_TYPE_GROUP_L 0x11 //Sensor Type Group (Low Byte)
#define SENSOR_TYPE_SUBGROUP 0x21 //Sensor Type Sub-Group
#define AVAILABLE_PHYSICAL_MEASUREMENTS 0x31 //Available Physical Measurement flags
#define SENSOR_TYPE_GROUP_H 0x41 //Sensor Type Group (High Byte)
#define READ_CUSTOM_ADDRESS 0x51 //Read the byte specified by the custom address pointer
#define STATUS_BYTE 0x71 //Measurement status flags
#define HUMIDITY_L 0x81 //Measure1/Humidity Value (Low Byte)
#define HUMIDITY_H 0x91 //Measure1/Humidity Value (High Byte)
#define TEMPERATURE_L 0xA1 //Measure2/Temperature Value (Low Byte)
#define TEMPERATURE_H 0xB1 //Measure2/Temperature Value (High Byte)
#define AIR_VELOCITY_L 0xC1 //Measure3/Air Velocity Value (Low Byte)
#define AIR_VELOCITY_H 0xD1 //Measure3/Air Velocity Value (High Byte)
#define CO2_AVG_L 0xC1 //Measure3/CO2 Avg Value (Low Byte)
#define CO2_AVG_H 0xD1 //Measure3/CO2 Avg Value (High Byte)
#define CO2_L 0xE1 //Measure4/CO2 Value (Low Byte)
#define CO2_H 0xF1 //Measure4/CO2 Value (High Byte) - Original comms code from: https://github.com/blueberrye-io/BB-EE893
- EE893 Datasheet: http://downloads.epluse.com/fileadmin/data/product/ee893/datasheet_EE893.pdf
- E2 Protocol specification: http://downloads.epluse.com/fileadmin/data/sw/Specification_E2_Interface.pdf