Altera QDRII SRAM Controller MegaCore Function - Manual (Page 62)

3–30 MegaCore Version 9.1 Altera Corporation
QDRII SRAM Controller MegaCore Function User Guide November 2009
Parameters
Memory
Table 3–8 shows the memory type parameters.
Table 3–8. Memory Type Parameters
Parameter Value Description
Memory device Part number A part number for a particular
memory device. Choosing an entry
other than Custom sets many of the
parameters in the wizard to the
correct value for the specified part. If
any such parameter is changed to a
value that is not supported by the
specified device, the preset
automatically changes to custom.
You can add your own devices to
this list by editing the
memory_types.dat file in the
\constraints directory.
QDRII or
QDRII+ Selects QDRII or QDRII+ SRAM
devices.
Clock speed Up to
300 MHz
(1)
The memory controller clock
frequency. The constraints script
and the datapath use this clock
speed. It must be set to the value
that you intend to use. The first time
you use IP Toolbench or if you turn
on Automatically generate the
PLL, it uses this value for the IP
Toolbench-generated PLL’s input
and output clocks .
Voltage 1.5 or 1.8 V Memory device voltage.
Burst length 2/4 Burst length.
Data bus width 8, 9, 16, 18,
32, 36 QDRII SRAM device width.
Address bus width 15 to 23 Memory space.
Memory latency For QDRII,
1.5; for
QDRII+, 2.0
or 2.5 The memory latency. QDRII+ is
bursts of four only.
Note to Table 3–8 :
(1) IP Toolbench allows you to enter up to 600 MHz, but Altera only supports the
QDRII SRAM controller up to 300 MHz.