Button boxes for E-Prime parallel port card:
Settings in E-prime script need to take account of inversion of button box responses. Also E-prime settings need to specify the parallel port as &HFDF9 for all the S&LG laptops (using a parallel port card) and &H379 for desktop computers. Red/pos. response button = 5 Black/neg. response button = 4
Following discussions with Maarten, Mark has overcome the known problems with the prototype buttons for the parallel port cards on the laptops - i.e. grounding problems, the mapping of bits-pins, and the spurious triggering.
I have tried parallel port button boxes Nos. 1-4 made for the S&LG using a script by MaartenVanCasteren, "test_ports.ebs" with the following results. Test Scriptlet: test_ports.ebs2
The keypress response is inverted on button box compared with the keyboard. Button box: negative on press, positive on release. Red/pos. response button = 5 goes to -5 when pressed. Black/neg. response button = 4 goes to -4 when pressed. Keyboard keypress responses are positive on press, negative on release.
The button boxes appear not to lock out a second button press (e.g. if red button depressed and black button pressed, then the black button response appears to overwrite on the screen display used in testing); however, MvC says that the first response will be stored by E-prime.
-- Main.SallyButterfield - Sept '08