XC2S100E-7PQ208C Xilinx, Inc., XC2S100E-7PQ208C Datasheet - Page 21

• Manufacturer Part Number: XC2S100E-7PQ208C
• Description: 100000 SYSTEM GATE 1.8 VOLT FPGA - NOT RECOMMENDED for NEW DESIGN
• Manufacturer: Xilinx, Inc.

Slave Serial Mode
In Slave Serial mode, the FPGA’s CCLK pin is driven by an
external source, allowing FPGAs to be configured from
other logic devices such as microprocessors or in a
daisy-chain configuration.
a Master Serial FPGA configuring a Slave Serial FPGA
from a PROM. A Spartan-II device in slave serial mode
should be connected as shown for the third device from the
left. Slave Serial mode is selected by a <11x> on the mode
pins (M0, M1, M2).
Figure 16
The serial bitstream must be setup at the DIN input pin a
short time before each rising edge of an externally
generated CCLK.
Notes:
1.
DS001-2 (v2.8) June 13, 2008
Product Specification
PROGRAM
If the DriveDone configuration option is not active for any of the FPGAs, pull up DONE with a 330Ω resistor.
shows the timing for Slave Serial configuration.
R
M2
PROGRAM
DONE
(Master Serial)
M0 M1
Spartan-II
Figure 15
GND
Figure 15: Master/Slave Serial Configuration Circuit Diagram
V
V
DOUT
CCLK
3.3V
CCO
CCINT
INIT
DIN
shows connections for
2.5V
3.3V
3.3 K
www.xilinx.com
CLK
DATA
CE
RESET/OE
Multiple FPGAs in Slave Serial mode can be daisy-chained
for configuration from a single source. The maximum
amount of data that can be sent to the DOUT pin for a serial
daisy chain is 2
bits, which is approximately 25 XC2S200 bitstreams. The
configuration bitstream of downstream devices is limited to
this size.
After an FPGA is configured, data for the next device is
routed to the DOUT pin. Data on the DOUT pin changes on
the rising edge of CCLK. Configuration must be delayed
until INIT pins of all daisy-chained FPGAs are High. For
more information, see
GND
3.3V
Vcc
PROM
CEO
Spartan-II FPGA Family: Functional Description
20
-1 (1,048,575) 32-bit words, or 33,554,400
"Start-up," page
M2
DIN
CCLK
PROGRAM
DONE
M0 M1
Spartan-II
(Slave)
GND
V
V
3.3V
DOUT
19.
CCO
CCINT
INIT
2.5V
Module 2 of 4
DS001_15_060608
21