Preliminary Information
Cyclone FPGA Family Data Sheet
Figure 20. Read/Write Clock Mode in Simple Dual-Port Mode
Note (1)
6 LAB Row
Clocks
Memory Block
256 × 16
512 × 8
6
1,024 × 4
2,048 × 2
4,096 × 1
data[ ]
D
ENA
Q
Data In
To MultiTrack
Interconnect
Data Out
D
Q
ENA
address[ ]
Read Address
D
Q
Q
Q
ENA
wraddress[ ]
Write Address
Byte Enable
Read Enable
D
ENA
byteena[ ]
rden
D
ENA
D
Q
ENA
wren
rdclken
Write
Pulse
Generator
D
ENA
Q
wrclken
wrclock
Write Enable
rdclock
Note to Figure 20:
(1) All registers shown except the rden register have asynchronous clear ports.
Single-Port Mode
The M4K memory blocks also support single-port mode, used when
simultaneous reads and writes are not required. See Figure 21. A single
M4K memory block can support up to two single-port mode RAM blocks
if each RAM block is less than or equal to 2K bits in size.
Altera Corporation
33