EP3C16F256I7N Altera, EP3C16F256I7N Datasheet - Page 47

• Manufacturer Part Number: EP3C16F256I7N
• Description: Cyclone III
• Manufacturer: Altera

Chapter 3: Memory Blocks in the Cyclone III Device Family
Memory Modes
Figure 3–10. Cyclone III Device Family Simple Dual-Port Timing Waveforms
True Dual-Port Mode
© December 2009
q (asynch)
wraddress
rdaddress
wrclock
rdclock
wren
data
rden
1
Altera Corporation
din-1
doutn-1
an-1
Figure 3–10
dual-port mode with unregistered outputs. Registering the outputs of the RAM
simply delays the q output by one clock cycle.
True dual-port mode supports any combination of two-port operations: two reads,
two writes, or one read and one write, at two different clock frequencies.
shows the Cyclone III device family true dual-port memory configuration.
Figure 3–11. Cyclone III Device Family True Dual-Port Memory
Note to
(1) True dual-port memory supports input or output clock mode in addition to the independent clock mode shown.
The widest bit configuration of the M9K blocks in true dual-port mode is 512 × 16-bit
(18-bit with parity).
bn
Figure
an
din
3–11:
shows the timing waveforms for read and write operations in simple
doutn
b0
a0
a1
data_a[ ]
address_a[ ]
wren_a
byteena_a[]
addressstall_a
clocken_a
rden_a
aclr_a
q_a[]
clock_a
dout0
a2
b1
a3
addressstall_b
address_b[]
byteena_b[]
clocken_b
data_b[ ]
clock_b
wren_b
rden_b
aclr_b
q_b[]
din4
b2
a4
(Note 1)
Cyclone III Device Handbook, Volume 1
din5
a5
b3
a6
din6
Figure 3–11
3–11