f.a.q.
frequently asked
How to
install the Java-Plugin?
In order to run the
ENIAC simulation, you need the Java runtime environment
version 1.4 (minimum) installed on your computer. Check
this link for download: http://www.java.com/download/.
How to start?
If you
loaded the default configuration, you don't need to set
any switches or cables. The machine is already
configured to do a basic computation (2+5*8) an running
in idle mode. You just need to press the go-button of
the Initiating-Unit. The Initiating unit can be found
to the left.
How can I write my own program?
Programming the ENIAC meant to set switches and
to plug cables. Try to understand the example programs
first and modify them little by little, before you
start designing your own programs.
How to set cables?
Just
click a connector with the left mouse button, drag the
cable to the target connector and release the mouse. To
change a cable, click one of its ends and drag it to
another connector. To remove a cable, click one end,
drag the cable to an area that is not covered by a
connector and release it.
I set up a program, but nothing
happens.
Every unit has its own power supply
and needs to be switched on separately. As well the
interconnectors of the Accumulators must be wired:
Check the Fibonacci-configuration to see how.
known bug
At Mac OS X / JDK 1.4 the simulation main window cannot be scrolled and is automatically centered. This behaviour seems to be caused by the Macintosh implementation of the Java virtual machine. There is no stack-trace written to System.err, so there is no line number, and the origin of the bug cannot be determined. Instead there is a message written to the output, that might be originated by the Mac OS X window manager:
xorSurfacePixels INVALID parameters: x=0, y=0, w=95
h=59
biqsdo->width=95, biqsdo->height=59,
biqsdoPixels->width=24, biqsdoPixels->height=30
I have no idea for a workaround. Sorry. I hope this problem can be fixed with a new version of the JDK.