Motorola MVME162, User Manual

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Functional Description
4-4 User’s Manual
4
C
aution
Lithium batteries incorporate flammable materials such as
lithium and organic solvents. If lithium batteries are mis-
treated or handled incorrectly, they may burst open and
ignite, possible resulting in injury and/or fire.
When dealing with lithium batteries, carefully follow the precautions listed
below in order to prevent accidents.
❏
Do not short-circuit.
❏
Do not disassemble, deform, or apply excessive pressure.
❏
Do not heat or incinerate.
❏
Do not apply solder directly.
❏
Do not use different models, or mix new and old batteries together.
❏
Do not charge.
❏
Always check proper polarity.
To remove the battery from the module, carefully pull the battery from the
socket.
Before installing a new battery, ensure that the battery pins are clean. Note the
battery polarity and press the battery into the socket. When the battery is in
the socket, no soldering is required.
Onboard DRAM
The MVME162 offers a 1MB, a 4MB, and an 8MB DRAM option. The DRAM
architecture is non-interleaved for 1MB and interleaved for 4MB and 8MB.
Parity protection can be enabled with interrupts or bus exception when a
parity error is detected. DRAM performance is specified in the section on the
DRAM Memory Controller in the MCchip Programming Model in the
MVME162 Embedded Controller Programmer’s Reference Guide.
The DRAM map decoder can be programmed to accommodate different base
address(es) and sizes of mezzanine boards. The onboard DRAM is disabled
by a local bus reset and must be programmed before the DRAM can be
accessed. Refer to the MCchip description in the MVME162 Embedded
Controller Programmer’s Reference Guide for detailed programming information.
Most DRAM devices require some number of access cycles before the DRAMs
are fully operational. Normally this requirement is met by the onboard refresh
circuitry and normal DRAM initialization. However, software should insure
that a minimum of 10 initialization cycles are performed to each bank of RAM.