Altera Cyclone IV - Page 180

8–16 Chapter 8: Configuration and Remote System Upgrades in Cyclone IV Devices
Configuration
Cyclone IV Device Handbook, May 2013 Altera Corporation
Volume 1
Figure 8–4. Multi-Device AS Configuration in Which Devices Receive the Same Data with Multiple .sof
Notes to Figure 8–4:
(1) Connect the pull-up resistors to the V
CCIO
supply of the bank in which the pin resides.
(2) Connect the pull-up resistor to the V
CCIO
supply voltage of the I/O bank in which the nCE pin resides.
(3) The
nCEO pin is left unconnected or used as a user I/O pin when it does not feed the nCE pin of another device.
(4) The
MSEL pin settings vary for different configuration voltage standards and POR time. You must set the master device in AS mode and the slave
devices in PS mode. To connect the
MSEL pins for the master device in AS mode and the slave devices in PS mode, refer to Table 8–3 on page 8–8,
Table 8–4 on page 8–8, and Table 8–5 on page 8–9. Connect the
MSEL pins directly to V
CCA
or GND.
(5) Connect the series resistor at the near end of the serial configuration device.
(6) Connect the repeater buffers between the master and slave devices for
DATA[0] and DCLK . All I/O inputs must maintain a maximum AC voltage
of 4.1 V. The output resistance of the repeater buffers must fit the maximum overshoot equation outlined in “Configuration and JTAG Pin I/O
Requirements” on page 8–5.
(7) The 50- series resistors are optional if the 3.3-V configuration voltage standard is applied. For optimal signal integrity, connect these 50- series
resistors if the 2.5- or 3.0-V configuration voltage standard is applied.
(8) These pins are dual-purpose I/O pins. The
nCSO pin functions as FLASH_nCE pin in AP mode. The ASDO pin functions as DATA[1] pin in AP and
FPP modes.
(9) Only Cyclone IV GX devices have an option to select
CLKUSR (40 MHz maximum) as the external clock source for DCLK .
(10) For multi-devices AS configuration using Cyclone IV E with 1,0 V core voltage, the maximum board trace-length from the serial configuration
device to the junction-split on both
DCLK and Data0 line is 3.5 inches.
nSTATUS
nCONFIG
CONF_DONE
nCE
DATA[0]
DCLK
nCEO
N.C. (3)
(4)
Cyclone IV Slave Device
nSTATUS
nCONFIG
CONF_DONE
nCE
DATA[0]
DCLK
nCEO
N.C. (3)
(4)
V
CCIO
(1)
V
CCIO
(1)
nSTATUS
nCONFIG
CONF_DONE
nCE
DATA[0]
DCLK
nCEO
MSEL[ ]
N.C. (3)
(4)
nSTATUS
nCONFIG
CONF_DONE
nCE
DATA[0]
DCLK
nCSO (8)
ASDO (8)
nCEO
(4) MSEL[ ]MSEL[ ]
MSEL[ ]
DATA
DCLK
nCS
ASDI
Serial Configuration
Device
GND
V
CCIO
(1)
V
CCIO
(2)
10 kΩ
10 kΩ
10 kΩ
10 kΩ
(5)
25
Ω
(5),
50
Ω
(7)
Buffers (6)
(7)
50
Ω
Cyclone IV Slave Device
Cyclone IV Slave Device
Cyclone IV Master Device
CLKUSR
(9)
(10)
(10)