|
Extending
the TTL Capabilities of Neuralynx Acquisition Systems
Many people do
not know that the Cheetah Data Acquisition Software (DAS) is capable
of extending the TTL input and output capabilities of all Neuralynx
acquisition systems. All that is required is a DIO card
(available with 24, 48 or 96 TTL bits), which you can obtain by
contacting sales@neuralynx.com.
Upon receiving the DIO card, follow all of the included
manufacturer's installation and setup instructions before attempting
to use it with Cheetah DAS. While running the manufacturer's
setup software, write down the board number that is assigned to the
new board, as it will be needed later.
After installation and setup is complete, you will then be able to
configure Cheetah DAS to take advantage of your new TTL capabilities.
Adding a DIO card to Cheetah DAS is identical to adding an
acquisition system. Since no premade DIO card configuration
file is installed with Cheetah DAS (a problem that will be rectified
in the next release), we will just add the following command to the
bottom of the main configuration file:
-AddDigitalIOBoard DigitalIOBoard1 <board_type>
<board_number>
The main configuration file is normally Cheetah.cfg, but can also be
any custom configuration file that you use. The
<board_type> depends on which version of the DIO card was
ordered from Neuralynx. See the Cheetah Reference Guide's
Digital IO Commands section for a list of <board_type>
options. The <board_number> is the board number you
obtained from the manufacturer's setup utility.
Before the new TTL card can be of much use, you will need to define
how the TTL bits will be used. In the following example, we are
going to add a 24 TTL DIO card at board 0 and set the first port as a
TTL output and the second port as a TTL input:
-AddDigitalIOBoard DigitalIOBoard1 MeasurementComputingDio24 0
-SetDigitalIOPortDirection DigitalIOBoard1 0 Output
-SetDigitalIOPortDirection DigitalIOBoard1 1 Input
-SetDigitalIOInputEventsEnabled DigitalIOBoard1 1 True
After the card has been added to the system, all TTL inputs will be
recorded to event data files (NEV) just as those of your acquisition
system's onboard TTL port.
There are a couple of limitations that these TTL add-ons have that
the built-in TTLs do not. First of all, the TTL values are not
saved to a raw data file (RDF) during recording. So when the
RDF is played back, you will not have any of the TTLs from the extra
card show up. Second, there is no way to control TTL output
directly from Cheetah DAS. You will need to create a NetCom
program that sends commands or manually load a configuration file
each time you want a sequence of commands to execute. The
NetCom approach is much preferred for controlling an experiment as it
will not interfere with Cheetah DAS's normal operation. Many of
our experiment control programs have the ability to send any command
to Cheetah DAS, and the NetComExampleCommands example project that is
included in the NetCom Development package can be used to simply send
commands to Cheetah DAS on demand.
For more advanced setup options and a list of all control commands,
see the Cheetah Reference Guide's Digital IO Commands section.
If you have any questions or suggestions on how to improve the
additional TTL functionality in Cheetah DAS, contact support@neuralynx.com
.
|
