Pin Description
Table 2–8. External Flash Interface Pins (Part 1 of 2)
Pin Name
Pin Type
Description
A[20..0]
Input
These pins are the address input to the flash memory for read and write
operations. The addresses are internally latched during a write cycle.
When the external flash interface is not used, leave these pins floating
(with the few exceptions noted below). These flash address, data, and
control pins are internally connected to the configuration controller.
In the 100-pin PQFP package, four address pins (A0, A1, A15, A16) are
not internally connected to the controller. These loop back connections
must be made on the board between the C-A[]and F-A[]pins even
when not using the external flash interface. All other address pins are
connected internal to the package.
All address pins are connected internally in the 88-pin Ultra FineLine BGA
package.
Pin A20in EPC16 devices, pins A20and A19in EPC8 devices, and pins
A20, A19, and A18in EPC4 devices are no-connects. These pins should
be left floating on the board.
DQ[15..0]
Bidirectional
This is the flash data bus interface between the flash memory and the
controller. The controller or an external source drives DQ[15..0]during
the flash command and the data write bus cycles. During the data read
cycle, the flash memory drives the DQ[15..0]to the controller or
external device.
Leave these pins floating on the board when the external flash interface is
not used.
CE#
Input
Input
Active low flash input pin that activates the flash memory when asserted.
When it is high, it deselects the device and reduces power consumption
to standby levels. This flash input pin is internally connected to the
controller.
Leave this pin floating on the board when the external flash interface is not
used.
RP# (1)
Active low flash input pin that resets the flash when asserted. When high,
it enables normal operation. When low, it inhibits write operation to the
flash memory, which provides data protection during power transitions.
This flash input is not internally connected to the controller. Hence, an
external loop back connection between C-RP#and F-RP#must be made
on the board even when you are not using the external flash interface.
When using the external flash interface, connect the external device to the
RP#pin with the loop back.
2–22
Altera Corporation
August 2005
Configuration Handbook, Volume 2
ALTERA [ ALTERA CORPORATION ]
