Settings files

local_settings.py

Contains one constant, ACCESS_CODE, which stores the access code to ‘authenticate’ communication with the server.

settings.py

Change the variables in this file to specify:

1. component pin numbers on GPIO board,
2. default PID parameters,
3. website URL or IP address to which data is sent,
4. time intervals to measure and send data

Some parameters can be controlled by the website’s Calibrate page, and the corresponding params listed here are defaults in case web connection fails.

Jin Cheng, 12/12/16:

Moved all hardware settings that are sensitive to circuitry changes to this separate file for easy & quick changes.

Jin Cheng, 17/01/16:

Added Web API settings.

robotchem.settings.BLUE = 21

Blue LED GPIO output pin number.

robotchem.settings.CURRENT_SENSOR_REF_CHANNEL = 1

Analog-digital converter channel used for the current sensor on the reference heater.

robotchem.settings.CURRENT_SENSOR_SAMPLE_CHANNEL = 3

Analog-digital converter channel used for the current sensor on the sample heater.

robotchem.settings.DEBUG = True

Setting this to true enables a very basic logging system which just prints out to stdout various info about what the code is doing.

robotchem.settings.FAKE_HARDWARE = True

Sometimes it is useful to run main.py on a personal computer and disable hardware controls. Setting this to true will make hardware control functions just print out what it was supposed to do.

robotchem.settings.GREEN = 20

Green LED GPIO output pin number.

robotchem.settings.HEATER_REF_PIN = 12

Reference heater MOSFET PWM pin. Note this must be a hardware controlled GPIO pin.

robotchem.settings.HEATER_SAMPLE_PIN = 13

Reference heater MOSFET PWM pin. Note this must be a hardware controlled GPIO pin.

robotchem.settings.MAIN_LOOP_INTERVAL = 0.5

Main loop interval, in seconds. This is the increment between calculations of PID-controlled PWM when a job is active. Note the web API parameters override this setting.

robotchem.settings.MAX_RAMP_RATE = 20

Maximum increment in temperature (degrees Celsius) per minute. Note the web API parameters override this setting.

robotchem.settings.MAX_VOLTAGE = 3.3

Voltage supplied across the MOSFETs which power the Peltier heaters. Used to calculate energy used.

robotchem.settings.PID_PARAMS = {'P': 3.0, 'I': 0.6, 'D': 0.0}

Default PID controller parameter dictionary. Keys should be P, I, D which correspond to the proportional, integral and derivative factors. Note the web API PID parameters override this setting.

robotchem.settings.RED = 16

Red LED GPIO output pin number.

robotchem.settings.TEMP_READ_TIME_INTERVAL = 0.2

Temperature read time interval This is used during an active calorimetry job, during the main PID calculating loop

robotchem.settings.TEMP_SENSOR_BASE_DIR = '/sys/bus/w1/devices/'

Base directory of the 1-wire raspberry pi reader files.

robotchem.settings.TEMP_SENSOR_ID_APPENDIX = 'w1_slave'

Appendix to the file names for the 1-wire data files on the file system on Raspberry Pi.

robotchem.settings.TEMP_SENSOR_ID_REF = '3b-0cdc0388554f'

Identifier of the 1-wire reader port connected to the reference thermocouple.

robotchem.settings.TEMP_SENSOR_ID_SAMPLE = '3b-6cdc038848fb'

Identifier of the 1-wire reader port connected to the sample thermocouple.

robotchem.settings.TEMP_STABILISATION_MIN_DURATION = 15

The minimum time duration in which temperature must stabilise before the program moves on to the next code block.

robotchem.settings.TEMP_TOLERANCE = 1

The difference between temperature values for them to be considered ‘practically equal’

robotchem.settings.WEB_API_ACTIVE_INTERVAL = 5

Active job refresh interval. Note the web API parameters override this setting.

robotchem.settings.WEB_API_BASE_ADDRESS = 'http://robotchem.chengj.in/api/'

Web API base address.

robotchem.settings.WEB_API_IDLE_INTERVAL = 10

Idle refresh interval. Note the web API parameters override this setting.

robotchem.settings.WEB_API_MIN_UPLOAD_LENGTH = 5

Minimum number of measurements that justifies sending a HTTP request. Note the web API parameters override this setting.