Configuring Cyclone II Devices
Figure 13–15. Concurrent PS Configuration of Multiple Devices Using an Enhanced Configuration Device
V
V
CC
(1)
(1)
CC
Enhanced
Configuration
Device
10 kΩ (3) (3)
10 kΩ
Cyclone II Device 1
DCLK
DCLK
DATA0
DATA0
nSTATUS
CONF_DONE
nCONFIG
DATA1
(4)
N.C. nCEO
DATA[2..6]
OE (3)
V
nCE
CC
MSEL1
MSEL0
nCS (3)
nINIT_CONF (2)
GND
GND
Cyclone II Device 2
DCLK
DATA 7
DATA0
nSTATUS
CONF_DONE
nCONFIG
(4)
N.C. nCEO
V
nCE
CC
MSEL1
MSEL0
GND
GND
Cyclone II Device 8
DCLK
DATA0
nSTATUS
CONF_DONE
(4)
N.C. nCEO
nCONFIG
V
nCE
CC
MSEL1
MSEL0
GND
GND
Notes to Table 13–15:
(1) The pull-up resistor should be connected to the same supply voltage as the configuration device.
(2) The nINIT_CONFpin is available on enhanced configuration devices and has an internal pull-up resistor that is
always active, meaning an external pull-up resistor should not be used on the nINIT_CONFto nCONFIGline. The
nINIT_CONFpin does not need to be connected if its functionality is not used. If nINIT_CONFis not used, nCONFIG
must be pulled to VCC either directly or through a resistor (if reconfiguration is required, a resistor is necessary).
(3) The enhanced configuration devices’ OEand nCSpins 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.
(4) The nCEOpin can be left unconnected or used as a user I/O pin when it does not feed other device’s nCEpin.
The Quartus II software only allows you to set n to 1, 2, 4, or 8. However,
you can use these modes to configure any number of devices from 1 to 8.
For example, if you configure three FPGAs, you would use the 4-bit PS
mode. For the DATA0, DATA1, and DATA2lines, the corresponding SOF
data is transmitted from the configuration device to the FPGA. For
Altera Corporation
February 2007
13–41
Cyclone II Device Handbook, Volume 1
ALTERA [ ALTERA CORPORATION ]
