Cyclone Device Handbook, Volume 1
Figure 2–31. Control Signal Selection per IOE
Dedicated I/O
Clock [5..0]
io_coe
Local
Interconnect
io_csclr
Local
Interconnect
io_caclr
Local
Interconnect
io_cce_out
Local
Interconnect
io_cce_in
io_cclk
Local
Interconnect
ce_out
clk_out
sclr/preset
clk_in
ce_in
aclr/preset
oe
Local
Interconnect
In normal bidirectional operation, you can use the input register for input
data requiring fast setup times. The input register can have its own clock
input and clock enable separate from the OE and output registers. The
output register can be used for data requiring fast clock-to-output
performance. The OE register is available for fast clock-to-output enable
timing. The OE and output register share the same clock source and the
same clock enable source from the local interconnect in the associated
LAB, dedicated I/O clocks, or the column and row interconnects.
Figure 2–32 shows the IOE in bidirectional configuration.
2–44
Preliminary
Altera Corporation
January 2007