Millisecond Forums

Hello all!

I am programming an Experiment where a letter and number are presented together either on the left or Right side of the sreen​.

The given letters are:
B, D, E, ​G, H, L, N, R, T
The given numbers are:
​1, 2, 3, 4, 5, 6, 7, 8, 9
(all letters and numbers are Picture-Elements)
​
​The participants are able to react on the Symbols with the following keys of the Keyboard:
Symbol on the left side: 'A'
Symbol on the Right side: 'L'

​The Task is to press either the button for the letter or for the number; so the Task changes at each Trial. At the first Trial the participant has to push the button for the letters Position.

​The Arrangement is:
Trial​ 1: letter position
Trial 2: number position
Trial 3: letter position
Trial 4: number position
etc.

Question 1: All possible combinations:
​Is there a "quick" command to create all combinations or do I have to program each Trial separately?
For Example:
​Letter 'B' on the left side and number '1' on the Right side = Trial.b_1
​Letter 'B' on the right side and number '1' on the left side = Trial.1_b
etc.​

Question 2: Circle around first Trial:
​Is it possible to insert a White circle (Picture-element) around the target of the first Trial (letter) as an cue for orientation?

Question 3: Circle around Target of the next Trial after invalid previous trial
I would like to program that everytime ​the participant presses an invalid key, the target of the next Trial gets an circle, to help them Re-orienting.

If you Need further Information, feel free to ask!​
​Thank you very much!
Theo​​​​​​​​​​​​​​​​​​​​​​​