EP2AGX45DF29I5 Altera, EP2AGX45DF29I5 Datasheet - Page 67

• Manufacturer Part Number: EP2AGX45DF29I5
• Description: IC ARRIA II GX FPGA 45K 780FBGA
• Manufacturer: Altera
• Series: Arria II GXr

Specifications of EP2AGX45DF29I5

• Number Of Logic Elements/cells: 42959
• Number Of Labs/clbs: 1805
• Total Ram Bits: 3435
• Number Of I /o: 364
• Voltage - Supply: 0.87 V ~ 0.93 V
• Mounting Type: Surface Mount
• Operating Temperature: -40°C ~ 100°C
• Package / Case: 780-FBGA
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Number Of Gates: -

Chapter 3: Memory Blocks in Arria II Devices
Design Considerations
Figure 3–19. Read-During-Write Data Flow
Figure 3–20. MLABs Blocks Same Port Read-During Write: Don’t Care Mode
December 2010 Altera Corporation
Read-During-Write Behavior
q(unregistered)
q(registered)
address
data_in
wrena
clk_a
You can customize the read-during-write behavior of the Arria II memory blocks to
suit your design requirements. The two types of read-during-write operations are
same port and mixed port.
and mixed port.
Same-Port Read-During-Write Mode
This mode applies to either a single-port RAM or the same port of a true dual-port
RAM. In same-port read-during-write mode, three output choices are available: new
data mode (or flow-through), old data mode, or don’t care mode. In new data mode,
the new data is available on the rising edge of the same clock cycle on which it was
written. In old data mode, the RAM outputs reflect the old data at that address before
the write operation proceeds. In don’t care mode, the RAM outputs “don’t care”
values for a read-during-write operation.
Figure 3–20
behavior in don’t care mode for MLABs.
XX
XX
XX
Port A
data in
Port A
data out
XX
A0(old data)
shows sample functional waveforms of same-port read-during-write
FFFF
A0
FFFF
Figure 3–19
FFFF
Arria II Device Handbook Volume 1: Device Interfaces and Integration
A1(old data)
shows the difference between the same port
Port B
data in
Port B
data out
AAAA
A1
AAAA
AAAA
Mixed-port
data flow
Same-port
data flow
A2(old data)
XXXX
A2
3–21