CAUSE: A few parallel ports drive the signal lines so hard that they power the DS-EXP through the
signal lines. Because the 5V power in the DS-EXP does not go to zero, the power-on-reset circuit does not operate,
and the Datashuttle Express does not start correctly. Datashuttle Express with serial number 137 and higher
(revision R1.10 or higher) do not have this problem because the reset circuit was redesigned. This problem
can also be caused by a failure inside the Datashuttle Express. If the solution below does not work, the Datashuttle probably
needs to be repaired.
SOLUTION: 1) Apply power to the computer and Datashuttle at the same time, or 2) disconnect the parallel
cables from both connectors of the Datashuttle before connecting the power, or 3) apply power to the Datashuttle
before the computer (though in rare cases, this has caused problems starting the computer). This may sound odd,
but PC's behave differently, so try each case to see which works with your PC.
We have found some laptops that do not activate their printer ports at power up if there is nothing connected
to them. This can be solved by ensuring that the Datashuttle is connected and powered up when the laptop is
Often, the BIOS setup permits several different port modes, all the way from traditional Centronics to ECP. If there
is a 'No-IRQ' symptom, check the BIOS setup: some selectable modes actually disable the IRQ.