Add-On Cards
 These usually refer to NuBus cards which can be used for more accurate analog to digital and other conversions. At present only one type of National Instruments Board is supported in slot 5, and it seems to work. A future version will also support National Instruments Boards as selected in the company's control panel.
 You must select your board using the Preferences… option pop up menu under the Boards topic, which allows you to send or receive messages to a National Instruments Board. If you want the board to trigger the start of MacStim after a certain number of pulses from the board, then type in more than 0 for the number of pulses to ignore.
 You should check At Start Only if you wish to use the repeat indefinitely option without the requirement to get triggering pulses each time.
 Note that if you are using a board with trigger pulses (to sync the start of MacStim with another machine) then if the first background stimulus is a PICT, it will be displayed whilst MacStim awaits the correct number of triggers.
 You can cancel waiting for the board at any time by typing the command-period key combination.
 You can set the stimulus to be stopped via a trigger from an attached NuBus board by:
 1. Telling MacStim the board is to be used in the Preferences… dialog (File menu), by setting the Board options menu to that board. 
 2. Unchecking the Experiment options "Ignore stop events" check box (also in the Preferences… dialog).
 3. Using the trigger stop event in the stpEvt field of the correct trial you wish to be triggered.
The board's pulse count will be stored at the start of the stimulus presentation, and if the next trigger occurs at a latency greater than the minimum response time (Timing options in Preferences… dialog), then MacStim will record a triggered event (with the count recorded in the log window next to that trial).