92
MicroBlaze Development Kit Spartan-3E 1600 Edition User Guide
www.xilinx.com
UG257 (v1.1) December 5, 2007
Chapter 12:
SPI Serial Flash
R
UCF Location Constraints
Figure 12-2
provides the UCF constraints for the SPI serial Flash PROM, including the I/O
pin assignment and the I/O standard used.
Configuring from SPI Flash
To configure the FPGA from SPI Flash, the FPGA mode select pins must be set
appropriately and the SPI Flash must contain a valid configuration image.
Setting the FPGA Mode Select Pins
Set the FPGA configuration mode pins for SPI mode, as shown in
Figure 12-4
. The location
of the configuration mode jumpers (J30) appears in
Figure 12-3
.
Figure 12-2:
UCF Location Constraints for SPI Flash Connections
# some connections shared with SPI Flash, DAC, ADC, and AMP
NET "SPI_MISO" LOC = "N10" | IOSTANDARD = LVCMOS33 ;
NET "SPI_MOSI" LOC = "T4" | IOSTANDARD = LVCMOS33 | SLEW = SLOW | DRIVE = 6 ;
NET "SPI_SCK" LOC = "U16" | IOSTANDARD = LVCMOS33 | SLEW = SLOW | DRIVE = 6 ;
NET "SPI_SS_B" LOC = "U3" | IOSTANDARD = LVCMOS33 | SLEW = SLOW | DRIVE = 6 ;
NET "SPI_ALT_CS_JP11" LOC = "R12" | IOSTANDARD = LVCMOS33 | SLEW = SLOW | DRIVE = 6 ;
UG257_12_02_060806
Figure 12-3:
Configuration Options for SPI Mode
DONE Pin LED
(Light
s
u
p when FPGA
su
cce
ss
f
u
lly config
u
red)
S
partan-
3
E
Development Board
S
elect
S
PI Mode
us
ing
the J
u
mper
S
etting
s
t
ab
le.
(Remove top j
u
mper
a
nd
in
s
ert the
b
ottom two)
He
a
der J12
(X
S
PI Progr
a
mming)
J
u
mper J11
UG257_12_0
3
_061506
PROG_B P
us
h B
u
tton
S
witch
(Pre
ss
a
nd rele
as
e to
re
s
t
a
rt config
u
r
a
tion.)
J
u
mper JP8 (XP
S
I)
(When progr
a
mming
S
PI Fl
as
h
us
ing the X
S
PI
u
tility, in
s
ert j
u
mper to hold PROG_B pin low.)