EP20K400CB652C7 Altera, EP20K400CB652C7 Datasheet - Page 27

• Manufacturer Part Number: EP20K400CB652C7
• Description: APEX 20KC
• Manufacturer: Altera

Altera Corporation
Figure 15. ESB Product-Term Mode Control Logic
Local
Interconnect
Local
Interconnect
Local
Interconnect
Local
Interconnect
Dedicated
Clocks
Global
Signals
The programmable register also supports an asynchronous clear function.
Within the ESB, two asynchronous clears are generated from global
signals and the local interconnect. Each macrocell can either choose
between the two asynchronous clear signals or choose to not be cleared.
Either of the two clear signals can be inverted within the ESB.
shows the ESB control logic when implementing product-terms.
Parallel Expanders
Parallel expanders are unused product terms that can be allocated to a
neighboring macrocell to implement fast, complex logic functions.
Parallel expanders allow up to 32 product terms to feed the macrocell OR
logic directly, with two product terms provided by the macrocell and
30 parallel expanders provided by the neighboring macrocells in the ESB.
The Quartus II Compiler can allocate up to 15 sets of up to two parallel
expanders per set to the macrocells automatically. Each set of two parallel
expanders incurs a small, incremental timing delay.
APEX 20KC parallel expanders.
4
4
CLK2
APEX 20KC Programmable Logic Device Data Sheet
CLKENA2
CLK1
CLKENA1 CLR2
Figure 16
CLR1
Figure 15
shows the
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