MPC852TADS Freescale Semiconductor, MPC852TADS Datasheet - Page 50

• Manufacturer Part Number: MPC852TADS
• Description: Networking Modules & Development Tools ADS BOARD FOR 852
• Manufacturer: Freescale Semiconductor
• Type: Network Controller & Processorr

Specifications of MPC852TADS

• Memory Type: Flash, SDRAM
• Interface Type: RS-232, Ethernet, PCMCIA
• Operating Voltage: 1.8 V to 3.3 V
• Operating Temperature Range: 0 C to + 30 C
• Board Size: 233 mm x 150 mm
• Product: Modules
• For Use With/related Products: MPC852T
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

38
11. "BCSR1
Note: The DRAM is not populated on the board. As such users may populate their own DRAM in order to either
expand memory or to run old SW that ran on the old MPC8xxFADS.
4•6•1
In order to enhance evaluation capabilities and achieve the best fit for application requirements, support is given to
DRAM’s with 16-bit and 32-bit data bus widths. A DRAM in 16-bit mode is only 50% in use. For example, only the
memory portion connected to data lines D(16:31) is in use.
To configure the DRAM for a 16-bit data bus width operation, the following steps should be taken:
If a dual-bank DRAM SIMM is being used then perform the following:
If the above noted steps (1-5) are executed from a running code then, during execution, this code shouldn’t reside on
the DRAM for potentially erratic behavior may result in a system crash.
4•6•2
Projected DRAM performance figures are shown in
1)
2)
3)
4)
5)
Set the Dram_Half_Word bit in BCSR1 to Half-Word. See
The Port size bits of BR2~ (and of BR3~ for a 2-bank DRAM SIMM) should be set to 16-bits.
The AM bits in the OR2 register should be set to half of the nominal single-bank DRAM SIMM volume
or to a quarter of the nominal dual-bank DRAM SIMM volume.
If a contiguous DRAM block is required then set the base-address bits in the BR3 register to
DRAM_BASE plus a quarter Nominal_Volume.
The AM bits of the OR3 register should be set to a quarter of the Nominal_Volume.
DRAM 16-Bit Operation
DRAM Performance Figures
Description".
Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
Functional Description
MPC852TADS - User’s Manual
TABLE 4-2. "Regular DRAM Performance Figures"
TABLE 4-11. "BCSR1
Description".
Release 1.0
and in