xq2vp40 Xilinx Corp., xq2vp40 Datasheet - Page 38

• Manufacturer Part Number: xq2vp40
• Description: Qpro Virtex-ii Pro 1.5v Platform Fpgas Complete Data Sheet
• Manufacturer: Xilinx Corp.

Three-State Buffers
Introduction
Each Virtex-II Pro CLB contains two three-state drivers
(TBUFs) that can drive on-chip buses. Each three-state buffer
has its own three-state control pin and its own input pin.
Each of the four slices have access to the two three-state
buffers through the switch matrix, as shown in
TBUFs in neighboring CLBs can access slice outputs by direct
connects. The outputs of the three-state buffers drive horizontal
routing resources used to implement three-state buses.
X-Ref Target - Figure 33
The three-state buffer logic is implemented using AND-OR
logic rather than three-state drivers, so that timing is more
X-Ref Target - Figure 34
Table 12: Logic Resources in One CLB
Table 13: Virtex-II Pro Logic Resources Available in All CLBs
DS136-2 (v2.0) December 20, 2007
Preliminary Product Specification
Notes:
1.
XQ2VP40
XQ2VP70
Device
Slices
The carry-chains and SOP chains can be split or cascaded.
4
Figure 33: Virtex-II Pro three-state Buffers
R
CLB Array:
Row x Col.
104 x 82
Switch
88 x 58
Matrix
LUTs
8
of Slices
Number
19,392
33,088
Flip-Flops
Figure 34: Three-state Buffer Connection to Horizontal Lines
Slice
Slice
TBUF
TBUF
S1
S0
8
Switch
CLB-II
matrix
DS031_37_060700
Number
of LUTs
38,784
66,176
Slice
Slice
S3
S2
MULT_ANDs
Figure
8
Max Distributed SelectRAM
33.
Programmable
or Shift Register (bits)
connection
www.xilinx.com
1,058,816
620,544
Carry-Chains
Arithmetic &
predictable and less load dependant especially with larger
devices.
Locations / Organization
Four horizontal routing resources per CLB are provided for
on-chip three-state buses. Each three-state buffer has
access alternately to two horizontal lines, which can be
partitioned as shown in
corresponding to SelectRAM+ memory and multiplier or I/O
blocks are skipped.
Number of Three-State Buffers
Table 11
in each Virtex-II Pro device. The number of three-state
buffers is twice the number of CLB elements.
Table 11: Virtex-II Pro Three-State Buffers
CLB/Slice Configurations
Table 12
the CLBs are identical and each CLB or slice can be
implemented in one of the configurations listed.
shows the available resources in all CLBs.
XQ2VP40
XQ2VP70
2
Switch
CLB-II
matrix
Device
shows the number of three-state buffers available
summarizes the logic resources in one CLB. All of
Chains
SOP
Number of
2
Flip-Flops
38,784
66,176
Buffers per Row
Three-state
SelectRAM+
Distributed
Figure
DS031_09_032700
3 - state lines
128 bits
116
164
Carry-Chains
Number of
34. The switch matrices
116
164
Functional Description
Registers
128 bits
(1)
Shift
Total Number
state Buffers
of Three-
SOP Chains
16,544
9,696
Number of
Module 2 of 4
Table 13
176
208
TBUF
2
(1)
28