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www.xilinx.com
ML605 Hardware User Guide
UG534
(v1.2.1) January 21, 2010
Chapter 1:
ML605 Evaluation Board
3. 12
8
Mb Platform Flash XL
A 128 Mb Xilinx XCF128X-FTG64C Platform Flash XL device is used with an onboard
47 MHz oscillator (X4) to configure the FPGA in less than 100 ms from power valid as
required by the
PCI Express Card Electromechanical Specification
. This allows the PCIe
interface to be recognized and enumerated when plugged into a host PC.
To achieve the fastest configuration speed, the FPGA mode pins are set to Slave SelectMAP
and the onboard 47 MHz clock source external to the FPGA is used for configuration.
Configuration DIP switch S2, switch 1, controls the 47 MHz oscillator enable as outlined in
“18. Switches,” page 53
.
See S2 switch setting details in
Table 1-26, page 56
. Also, see the
“FPGA Design
Considerations for the Configuration Flash,” page 23
for FPGA design recommendations.
4. 32 MB Linear BPI Flash
A Numonyx JS28F256P30 Linear BPI Flash memory (P30) on the ML605 provides 32 MB of
non-volatile storage that can be used for configuration as well as software storage. The
Linear BPI Flash shares the dual use configuration pins in parallel with the XCF128
Platform Flash XL.
The P30_CS net is used to select the P30 or the XCF128. Power-on configuration is selected
by the P30_CS net which is tied to a dip switch S2 (selects pullup/pulldown) and is also
wired to an FPGA non-config pin. The dip switch allows power selection for the
configuration device P30 or XCF128XL. The dip switch selection can be overridden by the
FPGA after configuration by controlling the logic level of the P30_CS signal.
See S2 switch setting details in
Table 1-26, page 56
. For an overview on configuring the
FPGA, see
“Configuration Options,” page 73
.
Figure 1-3
shows a block diagram for the Platform Flash and BPI Flash.
X-Ref Target - Figure 1-3
Figure 1-3:
Platform Flash and BPI Flash Block Diagram
UG5
3
4_0
3
_011110
FPGA U1
B
a
nk
3
4
FLA
S
H_A[22:0]
FPGA U1
B
a
nk 24
FLA
S
H_A[2
3
]
FLA
S
H_D[15:0]
U4
U27
BPI
FLA
S
H
PLATFORM
FLA
S
H
A
D
A
A2
3
D
CE
E
FPGA U1
B
a
nk 24
U10
VCC2V5
VCC2V5
VCC2V5
PLATFLA
S
H_FC
S
_B
FLA
S
H_CE_B
FPGA_FC
S
_B
FPGA U1
B
a
nk 24
S
2
S
WITCH 2
ON = U4 BOOT
OFF = U27 BOOT
1
6
4
3
11
S
2-2
2
VCC2V5
7
S
2-6
510
4.7K
510
4.7K
6
S
2
S
WITCH 6
ON = U4 BPI Upper H
a
lf
OFF = U4 BPI Lower H
a
lf
P
3
0_C
S
_
S
EL
(FPGA U1 pin AJ12)
S
1
S
witch 4
OFF = Di
sab
le
S
y
s
tem ACE,
en
ab
le U4/U27 fl
as
h
b
oot
ON = En
ab
le
S
y
s
tem ACE
b
oot when
CF c
a
rd i
s
pre
s
ent