Masstorio-arduino

Arduino temperature control software with programs, and ramping

General Information

Masstorio-arduino was used to regulate a temperature-controlled nanospray mass spectrometry source. The controller code allows for isothermal regulation (single temperature), ramp-soak programs, and constant temperature ramping. The code here is only for the Arudino and was generally ran alongside a controller software on a PC.

While, this software was built for a specialized task, it can be quickly modified for other temperature-regulation functions.

Hardware considerations

Temperature is read using a thermistor circuit. Solid-state relays were used to control cartridge heaters. Only on-off control is supported.

Another relay was used to regulate a water circulator for cooling applications. You can ignore/omit this. It is not integral to the temperature-regulation operations.

Operating modes

Three main operation modes are present:

1. Isothermal control

2. Ramp-soak control

3. Constant-rate ramp control

Communication with the controller

Serial communication with the controller can be established with a baudrate of 57600 Serial commands are sent as strings ending with '\n'

Command structure:

6,2,X,Y,Z\n

The first integer specifies a request (3) or write (6) command. The second integer specifies the commmand type The later are variables, only applicable for write commands

Request commands

Process value (temperature)

3,1

Output value (0-100% heater output)

3,2   

State (enum STATE)

3,3     

typedef enum STATE
{
  STATE_INACTIVE, // nothing, cannot run or do anything
  STATE_ISO, // Isothermal control
  STATE_ACTIVE, // ready for Ramp soak program
  STATE_RAMP, // is ramping
  STATE_SOAK, // is soaking
  STATE_PAUSE,
  STATE_ERROR, // no T read
  STATE_HIGHTEMP
} State_t;

Ramp soak time (Time left for current step in msec)

3,4   

Status (enum STATUS)

3,5   

typedef enum STATUS
{
  STATUS_OFF, // normaly off
  STATUS_ON, // switches to ON during run
  STATUS_INITIATE, // starts a cycle
  STATUS_COMPLETE // cycle is completed
} Status_t;

Setpoint value (set temperature)

3,7   

PID gain values (returns three values)

3,8   

Mode (enum MODE)

3,9   

typedef enum MODE
{
  MODE_ISOTHERMAL, // isothermal operating mode
  MODE_RAMPSOAK, // ramp soak 
  MODE_RATE, // constant rate mode
} Mode_t;

Sequence details ( returns the parameter for a step in the uploaded program sequence)

3,10,ID,PARAM   

Sequence gains ( returns the gain for a step in the uploaded program sequence)

3,11,ID,PARAM   

Current step ( returns step in the running sequence program)

3,12   

Rate value ( returns constant ramp rate, if applicable)

3,13 

Direction ( returns temp control direction. 0 -> Heating; 1 -> cooling )

3,14  

Write commmands

License

This project is licensed under the MIT License - see the LICENSE.md file for details

Acknowledgements

This was influenced by ...