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Valve Module Serial Interface

Description

Allows the state machine or PC to control 8 solenoid valves, using the Bpod Valve Driver Module.

Requires a valve module board with firmware loaded from:

The valve module board must be connected to a serial port on the state machine module.

Command Interface

  • Byte 255 (reserved): Returns module info to state machine
  • 'O' (Byte 79): Opens a valve.
    • 'O' must be followed by:
      • A valve number (1-8) OR
      • The ASCII character of a valve number ('1' - '8') = (49 - 56)
  • 'C' (Byte 67): Closes a valve
    • 'C' must be followed by:
      • A valve number (1-8) OR
        • The ASCII character of a valve number ('1' - '8') = (49 - 56)
  • 'B' (Byte 66): Sets the state of multiple valves
    • 'B' must be followed by a byte. The 8 bits of the byte indicate valve states, for instance:
      • 1 = binary 00000001: valve 1 open, all others closed
      • 22 = binary 00010110: valves 2, 3 and 5 open, all others closed
  • All other bytes: Toggles state of valve
    • If byte 1-8, toggles state of valve 1-8
    • If ASCII character of '1' to '8' (49-56), toggles state of numeric equivalent valve (1-8)

Examples

Open and close valve 2 from the Arduino Serial Terminal:

At the terminal, type 'O2', then 'C2'

Open and close valve 2 from an ArCOM serial object in MATLAB: 

D = ArCOMObject('COM43', 115200);

D.write('O2', 'uint8');
D.write('C2', 'uint8');
clear D

Open and close valve 2 from the Bpod state machine 

LoadSerialMessages('ValveModule1', {['O' 2], ['C' 2]}); % Set serial messages 1 and 2

sma = NewStateMachine();
sma = AddState(sma, 'Name', 'OpenValve', ...
    'Timer', 0.1,...
    'StateChangeConditions', {'Tup', 'CloseValve'},...
    'OutputActions', {'ValveModule1', 1}); % Sends serial message 1

sma = AddState(sma, 'Name', 'CloseValve', ...
    'Timer', 0.1,...
    'StateChangeConditions', {'Tup', 'end'},...
    'OutputActions', {'ValveModule1', 2}); % Sends serial message 2

SendStateMachine(sma);
RawEvents = RunStateMachine;

This code is a loop that runs 8 times. On each iteration, it creates and runs a state machine with 2 states. The 2 states use the "toggle" op codes to open and close a valve. This code assumes all valves are initially closed.

for i = 1:8
    sma = NewStateMachine();

    sma = AddState(sma, 'Name', 'OpenValve', ...
        'Timer', 0.1,...
        'StateChangeConditions', {'Tup', 'CloseValve'},...
        'OutputActions', {'ValveModule1', i}); % Toggle valve i Open

    sma = AddState(sma, 'Name', 'CloseValve', ...
        'Timer', 0.1,...
        'StateChangeConditions', {'Tup', 'end'},...
        'OutputActions', {'ValveModule1', i}); % Toggle valve i Closed

    SendStateMachine(sma);
    RawEvents = RunStateMachine;
end