11
Manual PCIe-DIO-24HC PCI Express Digital I/O w/CTR
Buffer Mode Jumper
A means of enabling or disabling (tristating) the 74LVC8T245 input/output buffers
under program control is provided at the jumper position labeled TST/BEN. When the
jumper is in the BEN (Buffer Enable) position, the I/O buffers are always enabled.
When the jumper is in the TST (Tristate) position, enabled/disabled state is controlled
by a control register. See Chapter 5, Programming for a description.
Note
A jumper must be installed in EITHER the TST or the BEN position for the card to
function.
Buffer VCCIO
VCCIO signaling levels are globally configured via jumper selection. Refer to the
specifications chapter for signal levels for each possible selection.
Interrupt Mode Jumpers
Place the Interrupt Select 0 jumper in the INT position to select the Digital I/O interrupt
(port C bit 3).
Place the Interrupt Select 0 jumper in the EXT position to select the External Input
interrupt.
Install the IRQD jumper to enable the Digital I/O or External Input interrupts.
Install the IRQT jumper to enable the Timer generated interrupt.
The foregoing are the only manual setups necessary to use these cards. Input/Output
selection is done via software by writing to a control register in the PPI as described in
the Programming chapter of this manual.
