Pin Information
Page 21
Configuration Devices for SRAM-Based LUT Devices
January 2012
Altera Corporation
Pin Information
Table 20 lists the pin functions of the EPC1, EPC2, and EPC1441 devices during device
configuration.
f For more information about pin information of EPC devices, refer to the Enhanced f For more information about pin information of EPCS devices, refer to the Serial Table 20. EPC1, EPC2, and EPC1441 Device Pin Functions During Configuration (Part 1 of 3)
Pin Name
Pin Number
Pin Type
Description
8-Pin
20-Pin
PLCC
32-Pin
DATA
12
31
Output
Serial data output. The DATA pin connects to the DATA0 pin
of the FPGA. DATA is latched into the FPGA on the rising
edge of DCLK.
The DATA pin is tri-stated before configuration and when
the nCS pin is high. After configuration, the EPC2 device
drives DATA high, while the EPC1 and EPC1441 device
tri-state DATA.
DCLK
2
4
2
Bidirectional
Clock output when configuring with a single configuration
device or when the configuration device is the first
(master) device in a chain. Clock input for the next (slave)
configuration devices in a chain. The DCLK pin connects to
the DCLK pin of the FPGA.
Rising edges on DCLK increment the internal address
counter and present the next bit of data on the DATA pin.
The counter is incremented only if the OE input is held
high, the nCS input is held low, and all configuration data
has not been transferred to the target device.
After configuration or when OE is low, the EPC1, EPC2 and
EPC1441 device drive DCLK low.
OE
387
Open-drain
bidirectional
Output enable (active high) and reset (active low). The OE
pin connects to the nSTATUS pin of the FPGA.
A low logic level resets the address counter. A high logic
level enables DATA and the address counter to count. If this
pin is low (reset) during configuration, the internal
oscillator becomes inactive and DCLK drives low. For more
The OE pin has an internal programmable 1-k
resistor in
EPC2 devices. If internal pull-up resistors are used, do not
use external pull-up resistors on these pins. You can
disable the internal pull-up resistors through the Disable
nCS
and OE pull-ups on configuration device option.