PulsePal connection to Bpod, and its usage in "AddState" function

kawatani

Hi, all

I have a question about the usage of Bpod & PulsePal.
I recently bought PulsePal and am trying to use it from the Bpod.

1, connecting issue
When I typed following code,

P = PulsePalModule('COM5');

Following errors were backed.

Error: ArCOMObject_Bpod/read (line 367)
Error: The USB serial port did not return the requested number of bytes.

Error: PulsePalModule (line 92)
obj.nChannels = obj.Port.read(1, 'uint8');

I confirmed that the COM5 is actually the PulsePal port, and COM5 was recognized as " Arduino Duo", however this error remains occurred.
A simple type of "PulsePal" works, and the return is as follows.

Searching for Pulse Pal. Please wait.
Connecting with PsychToolbox serial interface (low latency).
Trying port COM3
Pulse Pal connected on port COM3

It seems to work well.
How can I connect Pulse Pal to the Bpod?

2, PulsePalModule usage

I have checked Forum and this page (https://sanworks.github.io/Bpod_Wiki/module-documentation/pulsepal-module/), but I couldn't find any Examples of code.

Do you have any code examples to use PulsePal in "Addstate" "OutputActions"?

Thank you for your kind help.

Hiro

Josh

Hello Hiro,

Pulse Pal is not a Bpod module, as it lacks the standard RS-485 interface that Bpod modules use to exchange low-latency byte messages with the state machine. As noted on the Bpod wiki here, the PulsePalModule class for MATLAB is used to control the Bpod Analog Output Module, when it is running PulsePalModule firmware. This firmware gives the analog output module the ability to generate pulse trains using Pulse Pal's parameter set.

Depending on what you want to do, you may be able to use BNC cables between the state machine's BNC output channels and Pulse Pal's trigger channels.
Can you please describe your application in more detail?

Thank you,
Josh

kawatani

Josh wrote[quote='Josh' pid='3372' dateline='1624586805']
Hello Hiro,

Pulse Pal is not a Bpod module, as it lacks the standard RS-485 interface that Bpod modules use to exchange low-latency byte messages with the state machine. As noted on the Bpod wiki here, the PulsePalModule class for MATLAB is used to control the Bpod Analog Output Module, when it is running PulsePalModule firmware. This firmware gives the analog output module the ability to generate pulse trains using Pulse Pal's parameter set.

Depending on what you want to do, you may be able to use BNC cables between the state machine's BNC output channels and Pulse Pal's trigger channels.
Can you please describe your application in more detail?

Thank you,
Josh

Hi Josh,

Thank you very much! I totally misunderstood about PulsePalModule.

We would like to control 2 or 3 LED for optogenetic stimulation via Bpod and change the pulse parameters according to the trial types.
(e.g. trial "1"... stimulate LED "A" at 20Hz, 5ms ; trial "2"... stimulate LED "A" at 5 Hz, 5ms; trial "3"... stimulate LED "A" at 20 Hz and stimulate LED "B" continuously.)
In this case, using Analog Output Module would be the best solution?

I checked following two pages.
WavePlayerSerialInterface - Bpod Wiki (google.com)
Analog output module protocols (sanworks.io)
If I want to use Analog Output Module in PulsePalModule firmware, is the output function is same as Waveplayer?
('OutputActions', {'WavePlayer1', ['P' 3 0]} % Play waveform#1 on channels 1 and 2.)

Thank you for your kind assistance,
Hiro

Josh

Hi Hiro,

If you're not modulating light intensity with pulse voltage (i.e. if the LED driver controls intensity and you just want a 5V pulse train to control its timing), you can actually use the state machine's BNC (5V) or LED (3.3V) output channels to control your LED driver. Each BNC or LED output channel can be linked to a separate global timer, which you'd trigger in 'output actions' when you want to start the pulse train. Example usage is given here (for a single pulse) and here (for a pulse train).

If you're using Pulse Pal firmware on the analog output module, the state machine interface is even simpler. You'd use
{'PulsePal1', N} where N is a byte whose bits indicate which channels to trigger. For instance,
{'PulsePal1', 3} would trigger ch1+2 as binary 3 = 0011.
If the TriggerMode parameter is set to 'Toggle', a trigger arriving during playback will stop playback.
I hope this helps!

-Josh

kawatani

Josh wrote[quote='Josh' pid='3378' dateline='1624888231']
Hi Hiro,

If you're not modulating light intensity with pulse voltage (i.e. if the LED driver controls intensity and you just want a 5V pulse train to control its timing), you can actually use the state machine's BNC (5V) or LED (3.3V) output channels to control your LED driver. Each BNC or LED output channel can be linked to a separate global timer, which you'd trigger in 'output actions' when you want to start the pulse train. Example usage is given here (for a single pulse) and here (for a pulse train).

If you're using Pulse Pal firmware on the analog output module, the state machine interface is even simpler. You'd use
{'PulsePal1', N} where N is a byte whose bits indicate which channels to trigger. For instance,
{'PulsePal1', 3} would trigger ch1+2 as binary 3 = 0011.
If the TriggerMode parameter is set to 'Toggle', a trigger arriving during playback will stop playback.
I hope this helps!

-Josh

Hello Josh,

Thank you for your kind help!
I will try the global timer protocol, and will try later analog output module after it arrives.

Thank you so much!

Hiro