M1AFS250-FGG256I Actel Corporation, M1AFS250-FGG256I Datasheet - Page 156

• Manufacturer Part Number: M1AFS250-FGG256I
• Description: Actel Fusion Family Of Mixed Signal Fpgas
• Manufacturer: Actel Corporation

Device Architecture
Note:
Figure 2-98 • I/O Block Logical Representation
2- 14 0
From FPGA Core
Fusion I/Os have registers to support DDR functionality (see the
page 2-141
I/O Registers
Each I/O module contains several input, output, and enable registers. Refer to
simplified representation of the I/O block.
The number of input registers is selected by a set of switches (not shown in
registers to implement single or differential data transmission to and from the FPGA core. The Designer
software sets these switches for the user.
A common CLR/PRE signal is employed by all I/O registers when I/O register combining is used. Input
register 2 does not have a CLR/PRE pin, as this register is used for DDR implementation. The I/O
register combining must satisfy some rules.
for more information).
To FPGA Core
I/O / CLR or I/O / PRE / OCE
I/O / D1 / ICE
I/O / OCLK
I/O / ICLK
I/O / Q0
I/O / Q1
I/O / OE
I/O / D0
CLR/PRE
CLR/PRE
ICE
Input
Reg
Input
Reg
R e visio n 1
1
3
OCE
OCE
ICE
Enable
Output
Output
Output
Reg
Reg
Reg
6
4
5
CLR/PRE
CLR/PRE
CLR/PRE
"Double Data Rate (DDR) Support" section on
Input
Reg
2
A
Y
Resistor Control
Pull-Up/Down
E = Enable Pin
Figure
and Slew-Rate Control
PAD
Signal Drive Strength
Figure 2-98
2-98) between
for a