XC3000 Xilinx Corp., XC3000 Datasheet - Page 29

• Manufacturer Part Number: XC3000
• Description: XC3000 Field Programmable Gate Array
• Manufacturer: Xilinx Corp.

Slave Serial Mode
In Slave Serial mode, an external signal drives the CCLK
input(s) of the FPGA(s). The serial configuration bitstream
must be available at the DIN input of the lead FPGA a short
set-up time before each rising CCLK edge. The lead device
then presents the preamble data (and all data that over-
Figure 29: Slave Serial Mode Circuit Diagram
November 9, 1998 (Version 3.1)
R
RESET
Computer
Micro
Port
I/O
STRB
D0
D1
D2
D3
D4
D5
D6
D7
+5 V
+5 V
XC3000 Series Field Programmable Gate Arrays
CCLK
DIN
INIT
RESET
M0
flows the lead device) on its DOUT pin. There is an internal
delay of 0.5 CCLK periods, which means that DOUT
changes on the falling CCLK edge, and the next device in
the daisy-chain accepts data on the subsequent rising
CCLK edge.
D/P
*
M1
FPGA
PWRDWN
I/O Pins
Other
DOUT
HDC
LDC
M2
5 k
General-
Purpose
User I/O
Pins
*
Optional
Daisy-Chained
LCAs with
Different
Configurations
Activated, a
5-k Resistor is
Required in
Series with M1
If Readback is
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