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Altera Corporation
41
APEX 20K Programmable Logic Device Family Data Sheet
Figure 26. APEX 20KE Bidirectional I/O Registers
Notes:
(1)
This programmable delay has four settings: off and three levels of delay.
(2)
The output enable and input registers are LE registers in the LAB adjacent to the bidirectional pin.
VCC
OE[7..0]
CLK[1..0]
ENA[5..0]
CLRn[1..0]
Peripheral Control
Bus
CLRN/
PRN
D
Q
ENA
VCC
4 Dedicated
Clock Inputs
Chip-Wide
Output Enable
CLK[3..0]
4
12
VCC
Chip-Wide
Reset
Input Pin to
Core Delay
(1)
Slew-Rate
Control
Open-Drain
Output
VCCIO
Optional
PCI Clamp
Output Register
t
Delay
Core to Output
Register Delay
Input Pin to Input
Register Delay
CLRN
DQ
ENA
VCC
Chip-Wide
Reset
Input Register
Output Register
CLRN
DQ
ENA
Chip-Wide Reset
VCC
OE Register
VCC
4 Dedicated
Inputs
Row, Column, FastRow,
or Local Interconnect
Clock Enable
Delay
(1)
Input Pin to
Core Delay
(1)
CO
Input Pin to
Core Delay
(1)