VersaLogic EPM-4, Reference Manual

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CPU
Reference – 26 EPM-4 Reference Manual
CPU
The ÉlanSC520 Microcontroller has a 32-bit, low-voltage AMD Am5x86 microprocessor at its
core. The maximum clock rate is 133 MHz. The Am5x86 has 16 kb of unified cache that supports
write-back and write-through policies. It is a high-performance 486 CPU achieving performance
results equal to a Pentium 75.
System RAM
M
EMORY
The EPM-4 has 64MB of SDRAM soldered on board.
•
Storage Capacity 64 MB
•
Voltage 3.3 Volt
•
Error Detection Code Not supported
•
Error Correction Not supported
•
Speed 66 MHz, 60 ns
CMOS RAM
C
LEARING
CMOS RAM
Jumper V1 can be moved to position [1-2] for 30 seconds to erase the contents of the CMOS
RAM. Be sure to move the jumper back to position [2-3] for normal operation.
Note: Operation of the board with jumper V1 in the erase position [1-2] is not supported
or recommended.
D
EFAULT
CMOS RAM S
ETUP
V
ALUES
After the CMOS RAM is cleared, the system will load default CMOS RAM parameters the next
time the board is powered on. The default CMOS RAM setup values will be used in order to boot
the system whenever the main CMOS RAM values are blank, or when the system battery is dead
or has been removed from the board.
Real Time Clock
The EPM-4 features a year 2000 compliant, battery-backed 146818 compatible real time
clock/calendar chip. Under normal battery conditions, the clock will maintain accurate
timekeeping functions during periods when the board is powered off.
S
ETTING THE
C
LOCK
The CMOS Setup utility (accessed by pressing the [DEL] key during a system boot) can be used
to set the time/date of the real time clock.