Xilinx Spartan-3A User Manual page 92

Chapter 12: SPI Serial Flash
Table 12-1: SPI Flash PROM Interface Signals
FPGA
Signal
Pin
SPI_MISO AB20
SPI_MOSI AB14
SPI_SCK AA20
SPI_SS_B Y4
ALT_SS_B Y5
DATAFLASH_WP C14
C15
DATAFLASH_RST
ST_SPI_WP C13
92
FPGA
SPI_MISO
(AB20)
SPI_MOSI
(AB14)
SPI_SCK
(AA20)
DATAFLASH_WP
(C14)
DATAFLASH_RST
(C15)
ST_SPI_WP
(C13)
ALT_SS_B
(Y5)
SPI_SS_B
(Y4)
Figure 12-2: SPI Serial Flash Interface
Direction
FPGA PROM Serial data: Master Input, Slave Output
FPGA PROM Serial data: Master Output, Slave Input
FPGA PROM Clock. Actively toggles during configuration. User I/O pin after
configuration.
FPGA PROM Asynchronous, active-Low slave select signal. Actively drives Low during
SPI Flash configuration mode. User I/O pin after configuration. Drive High
if unused. Steered to selected
93.
FPGA PROM Second, asynchronous, active-Low slave select signal. Pulled High during
configuration. User I/O pin after configuration. Drive High if unused.
Steered to selected
FPGA PROM Write-protect input to Atmel AT45DB161D PROM. Must be High to
program the PROM. Has external 4.7kΩ pull-up resistor.
Reset input to Atmel AT45DB161D PROM. Must be High to read, program,
FPGA PROM
or erase the PROM. Has external 4.7kΩ pull-up resistor.
FPGA PROM Write-protect input to ST M25P16 PROM. Must be High to program the
PROM. Has external 4.7kΩ pull-up resistor.
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16Mbit
AT45DB161D
10Ω
SI SO
SCK
WP
RST
CS
ROM-CS0 CSO-SEL
CSO-B ROM-CS1
SPI Flash Select
Jumpers (J1)
Description
"SPI Flash PROM Select Jumpers (J1)," page
"SPI Flash PROM Select Jumpers (J1)," page
Spartan-3A/3AN Starter Kit Board User Guide
16Mbit
M25P16
10Ω
D Q
C
W
'1' HLD
S
kΩ to
= 4.7 3.3V
UG334_c12_02_052407
93.
UG334 (v1.0) May 28, 2007
R