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Pin Description
Pin Description
Table 8 through Table 10 list the EPC device pins. These tables include configuration
interface pins, external flash interface pins, JTAG interface pins, and other pins.
Table 8. Configuration Interface Pins
Pin Name
Pin Type
Output
Description
Configuration data output bus. DATAchanges on each falling edge of DCLK. DATA
DATA[7..0]
is latched into the FPGA on the rising edge of DCLK
The DCLKoutput pin from the EPC device serves as the FPGA configuration clock.
DATAis latched by the FPGA on the rising edge of DCLK
The nCS pin is an input to the EPC device and is connected to the FPGA’s
DONEsignal for error detection after all configuration data is transmitted to
.
DCLK
Output
.
CONF
_
the FPGA. The FPGA will always drive nCSand OElow when nCONFIGis asserted.
This pin contains a programmable internal weak pull-up resistor of 6 K that can
be disabled or enabled in the Quartus II software through the Disable nCS and
OE pull-ups on configuration device option.
nCS
Input
The nINIT_CONFpin can be connected to the nCONFIGpin on the FPGA to
initiate configuration from the EPC device using a private JTAG instruction. This
pin contains an internal weak pull-up resistor of 6K that is always active. The
nINIT_CONF
Open-Drain Output
INIT
_CONFpin does not need to be connected if its functionality is not used. If
n
INIT
_
CONFis not used, nCONFIGmust be pulled to VCC either directly or
through a pull-up resistor.
This pin is driven low when POR is not complete. A user-selectable 2-ms or
100-ms counter holds off the release of OEduring initial power up to permit
voltage levels to stabilize. POR time can be extended by externally holding OElow.
OEis connected to the FPGA nSTATUSsignal. After the EPC device controller
Open-Drain
Bidirectional
OE
releases OE, it waits for the nSTATUS-OEline to go high before starting the FPGA
configuration process. This pin contains a programmable internal weak pull-up
resistor of 6 Kthat can be disabled or enabled in the Quartus II software
through the Disable nCS and OE pull-ups on configuration device option.
Enhanced Configuration (EPC) Devices Datasheet
January 2012 Altera Corporation
ALTERA [ ALTERA CORPORATION ]
