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2.2 Unpacking Precautions
Some components of WAFER-5821 SBC are very
sensitive to static electric charges and can be
damaged by a sudden rush of power. To protect it
from unintended damage, be sure to note these
precautions:
Ground yourself to remove any static charge
before touching the Wafer-5821 SBC. You can do it
by using a grounded wrist strap at all times or by
frequently touching any conducting materials that is
connected to the ground.
Handle your Wafer-5821 SBC by its edges. Don’t
touch IC chips, leads or circuitry if not necessary.
Do not plug any connector or jumper while the
power is on.
2.3 System Memory DRAM
There is one 144-pin SO-DIMM socket to accept
3.3V non-buffered SDRAM. The max. Memory size is
128MB.
2.4 Watch-Dog Timer Setting
Reading port 443H enables the Watchdog Timer.
It should be triggered before the time-out period ends,
otherwise it will assume the program operation is
abnormal and will issue a reset signal to start again,
or activate NMI to CPU. Reading port 043/843H
disables the Watchdog Timer. Refer to Appendix A
for detailed information
Summary of Contents for WAFER-5821
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