EP2C8T144I8N Datasheet, PDF (421/470 Pages) Altera Corporation – Cyclone II Device Handbook, Volume 1

Configuring Cyclone II Devices
Table 13–11. Dedicated Configuration Pins on the Cyclone II Device (Part 4 of 5)
Pin Name
nCEO
User Configuration
Mode Scheme
Pin Type
N/A if All
option
is on.
I/O if
option
is off.
Output
Description
This pin is an output that drives low when device
configuration is complete. In single device
configuration, you can leave this pin floating or use it
as a user I/O pin after configuration. In multiple
device configuration, this pin inputs the next device's
nCE pin. The nCEO of the last device in the chain can
be left floating or used as a user I/O pin after
configuration.
If you use the nCEO pin to feed next device’s nCE pin,
use an external 10-kΩ pull-up resistor to pull the
nCEO pin high to the V_{C CI O} voltage of its I/O bank to
help the internal weak pull-up resistor.
ASDO
nCSO
N/A in AS
AS
mode
I/O in
PS and
JTAG
mode
N/A in AS
AS
mode
I/O in
PS and
JTAG
mode
Output
Output
Use the Quartus II software to make this pin a user
I/O pin.
This pin sends a control signal from the Cyclone II
device to the serial configuration device in AS mode
and is used to read out configuration data.
In AS mode, ASDO has an internal pull-up that is
always active.
This pin sends an output control signal from the
Cyclone II device to the serial configuration device in
AS mode that enables the configuration device.
In AS mode, nCSO has an internal pull-up resistor
that is always active.
Altera Corporation
February 2007
13–67
Cyclone II Device Handbook, Volume 1