EP20K200C Datasheet, PDF (39/90 Pages) Altera Corporation – Programmable Logic

APEX 20KC Programmable Logic Device Data Sheet
The register in the APEX 20KC IOE can be programmed to power-up high
or low after configuration is complete. If it is programmed to power-up
low, an asynchronous clear can control the register. If it is programmed to
power-up high, an asynchronous preset can control the register. This
feature is useful for cases where the APEX 20KC device controls an active-
low input or another device; it prevents inadvertent activation of the input
upon power-up.
Figure 25 shows how fast bidirectional I/O pins are implemented in
APEX 20KC devices. This feature is useful for cases where the APEX 20KC
device controls an active-low input or another device; it prevents
inadvertent activation of the input upon power-up.
Altera Corporation
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