EP2S90F1020C5 Datasheet, PDF (654/768 Pages) Altera Corporation – Stratix II Device Handbook, Volume 1

Device Configuration Pins
Table 7–22. Dedicated Configuration Pins on the Stratix II and Stratix II GX Device (Part 9 of 10)
Pin Name
nRS
User Mode
Configuration
Scheme
I/O
PPA
Pin Type
Input
Description
Read strobe input. A low input directs the
device to drive the RDYnBSY signal on the
DATA7 pin.
If the nRS pin is not used in PPA mode, it
should be tied high. In non-PPA schemes, it
functions as a user I/O during configuration,
which means it is tri-stated.
RDYnBSY
After PPA configuration, nRS is available as a
user I/O pin and the state of this pin depends
on the Dual-Purpose Pin settings.
I/O
PPA
Output Ready output. A high output indicates that the
target device is ready to accept another data
byte. A low output indicates that the target
device is busy and not ready to receive
another data byte.
In PPA configuration schemes, this pin will
drive out high after power-up, before
configuration and after configuration before
entering user-mode. In non-PPA schemes, it
functions as a user I/O pin during
configuration, which means it is tri-stated.
After PPA configuration, RDYnBSY is
available as a user I/O pin and the state of this
pin depends on the Dual-Purpose Pin
settings.
7–102
Stratix II Device Handbook, Volume 2
Altera Corporation
January 2008