December 20, 2005
8
ddr_dq[3]
Data 3
J21
ddr_dq[4]
Data 4
M20
ddr_dq[5]
Data 5
K22
ddr_dq[6]
Data 6
N20
ddr_dq[7]
Data 7
J22
ddr_dq[8]
Data 8
T21
ddr_dq[9]
Data 9
P20
ddr_dq[10]
Data 10
T20
ddr_dq[11]
Data 11
T19
ddr_dq[12]
Data 12
U22
ddr_dq[13]
Data 13
P22
ddr_dq[14]
Data 14
U21
ddr_dq[15]
Data 15
U20
ddr_ba[0]
Bank Select 0
L23
ddr_ba[1]
Bank Select 1
M24
ddr_dm[0]
Write Mask0
M22
ddr_dm[1]
Write Mask1
N22
ddr_dqs[0]
Data Strobe0
M19
ddr_dqs[1]
Data Strobe1
N19
ddr_csn
Chip Select
L24
ddr_rasn
Row Address Strobe
M21
ddr_casn
Column Address Strobe
M23
ddr_wen
Write Enable
L21
ddr_clk
Clock
R20
ddr_clkn
Clock
R19
ddr_clke
Clock Enable
K21
3.3 Flash
The Virtex-4™ MB development board provides 4MB of flash memory (x16). A high-level block
diagram of the flash interface is shown below followed by a table describing the flash memory
interface signals.
Virtex-4 FPGA
LX25-FF668
Flash
(4MB)
Control
Data[0:15]
Address[0:20]
Figure 5 – Flash Interface
Table 4 – Flash Interface Pin Assignments
Signal Name
Description
FPGA Pin #
flash_addr[0]
Address 0
M2
flash_addr[1]
Address 1
T6
flash_addr[2]
Address 2
R5