Enhanced Configuration Devices (EPC4, EPC8 & EPC16) Data Sheet
Table 2–8. External Flash Interface Pins (Part 2 of 2)
Pin Name
Pin Type
Description
OE#
Input
Active low flash control input that is asserted by the controller or external
device during flash read cycles. When asserted, it enables the drivers of
the flash output pins.
Leave this pin floating on the board when the external flash interface is not
used.
WE# (1)
Input
Active low flash write strobe asserted by the controller or external device
during flash write cycles. When asserted, it controls writes to the flash
memory. In the flash memory, addresses and data are latched on the
rising edge of the WE#pulse.
This flash input is not internally connected to the controller. Hence, an
external loop back connection between C-WE#and F-WE#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
WE#pin with the loop back.
WP#
Input
This pin is usually tied to VCC or ground on the board. The controller does
not drive this pin because it could cause contention.
Connection to VCC is recommended for faster block erase/programming
times and to allow programming of the flash bottom boot block, which is
required when programming the device using the Quartus II software.
This pin should be connected to VCC even when the external flash
interface is not used.
VCCW
Supply
Block erase, full chip erase, word write, or lock bit configuration power
supply.
Connect this pin to the 3.3-V VCC supply, even when you are not using the
external flash interface.
RY/BY#
BYTE#
Output
Input
Flash asserts this pin when a write or erase operation is complete. This
pin is not connected to the controller.
Leave this pin floating when the external flash interface is not used.
This is flash byte enable pin and is only available for enhanced
configuration devices in the 100-pin PQFP package.
This pin must be connected to VCC on the board even when you are not
using the external flash interface (the controller uses the flash in 16-bit
mode).
Note to Table 2–8:
(1) These pins can be driven to 12 V during production testing of the flash memory. Since the controller cannot tolerate
the 12-V level, connections from the controller to these pins are not made internal to the package. Instead they are
available as two separate pins. You must connect the two pins at the board level (for example, on the printed circuit
board (PCB), connect the C-WE#pin from controller to F-WE#pin from the flash memory).
Altera Corporation
August 2005
2–23
Configuration Handbook, Volume 2
ALTERA [ ALTERA CORPORATION ]
