Scannerize your E-Prime code: Part 1 - General Setup

Note: Scanner compatible code is best written on a computer that has a serial port (many laptops do not have them) as there will be an error when the program tries to find the serial port that is referred to in the code.

Updated Sept 27, 2005 by Ryan Lett

Created July 28, 2005 by Ryan Lett

1. Setup E-studio

Double-click the experiment object in E-Studio.

Click the devices tab and click “Add…”

Choose Serial and click “OK”

Select the newly added serial device and click “Edit”

Change the COM Port setting to be 2 and click “OK”

Hit “OK” again. Your comm port is now setup for reading button responses.

2. Insert Scanner Code

I’ve created a set of routines and functions for use in the scanner. Because of the nature of these functions everything is defined in a global sense. For non-programmers, this means that they can be called from anywhere in your program. You can download this code and paste it directly into your user script section.

a) Where do I find the user script section?

Click the “View” menu and select “Script”. If there was already a check mark beside “Script” you might have to do this twice. Alternatively you can use the keys Alt+5 to do the same command. When the window pops up, if you look in the lower left-hand corner of that window, you will see 2 tabs: one called “User” one called “Full”. Click the “User” tab. This is where you will put all the scanner code. Everything in this user script area is global or applies everywhere.

b) Where do I get this scanner code?

You can download is right here: Glorious Scanner Code

3. User Scanner Code

So, now that you’ve setup your comm port and inserted your code, what do you do with it?

Well, here are a list of the functions contained within the scanner code. Included are descriptions of what they do and the results they return.

Note: Functions return information to the calling procedure, subroutines do not.

Command Name Information
Init_Scanner Subroutine

This command initializes scanner pulse codes, the timer, the key array, and the button mask.

Either Init_Scanner or Init_Beh must be called or your program will NOT work.

Init_Beh Subroutine
This command initializes behavioural pulse codes, the timer, the key array, and the button mask.
Either Init_Scanner or Init_Beh must be called or your program will NOT work.
Init_KeyArr Subroutine
This command initializes the key array. This command does not need to be called as it is called when Init_Scanner or Init_Beh are called.
mintomilli Function mintomilli(minutes As Integer) As Long
Converts minutes to milliseconds. Takes an integer and returns a long integer
e.g.
Dim temp as Long 

        temp = mintomilli(10)
temp is now set to 600000
initMask Subroutine
Reset all the button masks to off. This is essential to call when changing which buttons you want to use.
SetMask Function SetMask(allowed As String) As Integer
Turns the specified button on using a string representing a button. Return 1 on success and -1 on fail. No reason why it should fail but just in case do error checking.
"L1" = left thumb		"R1" = right thumb

"L2" = left index		"R2" = right index

"L3" = left middle		"R3" = right middle

"L4" = left ring		"R4" = right ring

"L5" = left pinky		"R5" = right pinky
e.g. Clearing the mask and setting a new one

initMask

Dim temp as Integer

temp = SetMask("L2")

temp = SetMask("L3")

The left index and middle finger buttons are now enabled.
Or you can setup your own subroutines and put them in the user script area at the bottom. 

Sub SetProbeMask

	initMask

	tempint = SetMask("R2")

	tempint = SetMask("R3")

	tempint = SetMask("R4")

	tempint = SetMask("R5")

End Sub

This sets the 4 fingers on the right hand.

GetMask Function GetMask() As String
Returns a string interpretation of the current button mask configuration. Used mostly for debugging. e.g. Continuing from the last example
Dim mask as String

mask = GetMask
mask is now set to “0110000000″ which is a binary representation of the mask.
GetResponse Function GetResponse(max As Integer) As String
Parameter max is time in milliseconds. Set max to -1 in order to not return until a button has been pressed. Returns the button that was pressed. e.g. “Right 2″
Dim button as String

button = GetResponse(1000)

button = GetResponse(-1)
The first call waits 1 second for a button press. The second call waits indefinately for a button press.
WaitForPulse Subroutine
Waits for a scanner pulse. Waits indefinately.
scannersync_start Subroutine
Waits for a scanner pulse and when it gets one starts the timer and sets the timer_on flag.
StartTime Subroutine
Starts the timer and sets the timer_on flag.
Warning: Do not use StartTimer as it does not set the timer_on flag and will result in failure when GetTime is used.
GetTime Function GetTime() As Double
Returns the ammount of time past since the timer was started.
Warning: Do not use GetTimer as it does not check the timer_on flag and will result in a program crash if the timer has not been started. e.g.

Dim temp as Double

temp = GetTime
Tic Function Tic() As Double
Sets the start point of an offest calculator. Returns the time marker that was set.
For use in conjunction with Toc(). If timer was not running, it starts and Toc returns 0.00 e.g.
Dim temp as Double

temp = Tic
Returns current time, e.g. 45.2574
Toc Function Toc() As Double
Calculates the amount of time since Tic() was called and returns that value. If called be e.g.
Dim diff as Double

diff = Toc
Returns time since last Tic call.
e.g. current time = 58.4863
diff = 13.2289

In the scanner code you’ve pasted into your program, there are a handful of global variables that should be reserved by the scanner functions. So you should avoid calling any new variables the same name as these unless you want really bad things to happen to your program.

REMEMBER: E-Basic is case insensitive which means button = Button = BUTTON = bUtToN etc.
Here’s a list of the variable names and their types:

PAR_PORT_ADDR const
PAR_PORT_BLANK_CODE const
PAR_PORT_PULSE_CODE const
SCANNER_PULSE_CODE const
SCANNER_BLANK_CODE const
BLANK_CODE Integer
PULSE_CODE Integer
timer_on Boolean
timer_start Double
InputCount Integer
validInputCount Integer
n_button Long
buttonStr String
ButtonStart Double
ButtonFlag Boolean
L_1 Boolean
L_2 Boolean
L_3 Boolean
L_4 Boolean
L_5 Boolean
R_1 Boolean
R_2 Boolean
R_3 Boolean
R_4 Boolean
R_5 Boolean

Notes

The following is a list of reserved words that should never be used as variable names or object names as the compiler will not know how to properly handle them. A general rule is if the word changes color, it shouldn’t be used as a variable. 

  • start
  • end
  • blank
  • string
  • str
  • int
  • time
  • timer