EP2C8T144C8N Datasheet, PDF (406/470 Pages) Altera Corporation – Cyclone II Device Handbook, Volume 1

PS Configuration
the five common signals (nCONFIG, nSTATUS, DCLK, DATA0, and
CONF_DONE) between the cable and the configuration device. You can
also remove the configuration device from the board when configuring
the FPGA with the cable. Figure 13–21 shows a combination of a
configuration device and a download cable to configure an FPGA.
Figure 13–21. PS Configuration with a Download Cable & Configuration Device Circuit
V_CC (1)
10 kΩ
(4)
VCC (1)
V_CC
10 kΩ
(5)
Cyclone II FPGA
MSEL0
MSEL1
CONF_DONE
nSTATUS
DCLK
VCC (1)
10 kΩ
(5)
nCE
nCEO N.C. (6)
USB Blaster, ByteBlaster II,
MasterBlaster, or ByteBlasterMV
10-Pin Male Header
(Passive Serial Mode)
Pin 1
VCC
GND
VIO (2)
GND
DATA0
nCONFIG
(3)
(3)
(3) (3)
(3)
GND
Configuration
Device
DCLK
DATA
OE (5)
nCS (5)
nINIT_CONF (4)
Notes to Figure 13–21:
(1) The pull-up resistor should be connected to the same supply voltage as the configuration device.
(2) Pin 6 of the header is a V_IO reference voltage for the MasterBlaster output driver. V_IO should match the device’s
V_CCIO. Refer to the MasterBlaster Serial/USB Communications Cable Data Sheet for this value. In the ByteBlasterMV,
this pin is a no connect. In the USB-Blaster and ByteBlaster II, this pin is connected to nCE when it is used for AS
programming, otherwise it is a no connect.
(3) You should not attempt configuration with a download cable while a configuration device is connected to a
Cyclone II device. Instead, you should either remove the configuration device from its socket when using the
download cable or place a switch on the five common signals between the download cable and the configuration
device.
(4) The nINIT_CONF pin (available on enhanced configuration devices and EPC2 devices only) has an internal pull-up
resistor that is always active. This means an external pull-up resistor should not be used on the nINIT_CONF to
nCONFIG line. The nINIT_CONF pin does not need to be connected if its functionality is not used. If nINIT_CONF
is not used or not available (e.g., on EPC1 devices), nCONFIG must be pulled to V_CC either directly or through a
resistor (if reconfiguration is required, a resistor is necessary).
(5) The enhanced configuration devices’ OE and nCS pins have internal programmable pull-up resistors. If internal
pull-up resistors are used, external pull-up resistors should not be used on these pins. The internal pull-up resistors
are used by default in the Quartus II software. To turn off the internal pull-up resistors, check the Disable nCS and
OE pull-ups on configuration device option when generating programming files.
(6) The nCEO pin can be left unconnected or used as a user I/O pin when it does not feed other device’s nCE pin.
13–52
Cyclone II Device Handbook, Volume 1
Altera Corporation
February 2007