Intel
ยฎ
EP80579 Integrated Processor Product LineโSchematics Checklist
Intel
ยฎ
EP80579 Integrated Processor Product Line
Platform Design Guide May 2010
305 Order Number: 320068-005US
EX_ADDR[24:0]
โข Expansion Bus Address.
โข Connect to Expansion Bus on-
board devices and inbound/
outbound buffer
โข Strap EX_ADDR[23:21] as
shown below to determine LEB
Bus memory size.
Note:
โข BIOS can also be used to
configure the LEB_SIZE
through the MMBAR (Expansion
Bus Base Address Register)
instead of external strapping.
(Refer to EP80579 Datasheet)
โข The LEB controller allocates up to
256 MB of memory space to support
up to 8 devices on the LEB Bus. At
power-up or whenever RESET_IN#
is asserted, EX_ADDR[23:21] bits
are captured and stored by the LEB
controller to detemine the LEB
memory size (LEB_SIZE) and the
number of devices on the bus,
which also controls the active LEB
chip selects. The EX_ADDR[23:21]
should be externally strapped with
1Kฮฉ pull-ups and pull-downs to
determine the LEB_SIZE.
Note:
โข Can be left as no connect (NC)
when the LEB Bus is not connected
to an interfacing device or not used
LEB_SIZE Strapping Options:
EX_BE[1:0] I/O
โข Expansion Bus Byte Enables.
โข Used to select the particular
bytes that will be written or
read when executing inbound/
outbound HSS transfers.
Note:
โข Can be left as no connect (NC)
when the interface is not connected
to an interfacing device or not used
EX_CLK I
โข 33 MHz Expansion Clock
โข Use an External 33 MHz Clock
with a clock buffer
โข Connected to one of the
outputs from the Expansion
Clock Fanout Buffer.
โข Connect clock
through a 33 ฮฉ
ยฑ5% series resistor.
The EP80579 Expansion Bus connects to
several devices on the Platform.
โขFlash (2)
โขFPGA
โขHSS [3:0]
Each device should be connected to one
of the outputs from the clock fanout
buffer.
Note:
โข Connect EX_CLK to a 33 MHz clock
source when the interface is not
used or connected to other devices.
โขSee Section 2.3
Table 100. Schematic Checklist (Sheet 22 of 26)
Checklist Items
I/O Type
(Default)
Recommendations Comments
EX_ADDR
[23:21]
Strapping
LEB Memory Size
(LEB_SIZE)
# of
Devices
Supported
000 0 MB 0
001 32 MB 1
010 64 MB 2
011 128 MB 4
1XX 256 MB 8
Note: Strap EX_ADDR[23:21] = 000 or use
BIOS to configure LEB_SIZE = 0 MB if
the LEB Bus is not used.