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UBI EasyCoder 501 – Technical Manual
ELECTRONICS, cont'd.
RAM Memory
Real-time Clock Circuit
Fuse
IC-106, IC-107, IC-108 and IC-109
In these sockets either two or four SRAM
1
packages, which contain
the printer's working and storage memory, can be fitted. The SRAM
packages must have an access time of max. 120 ns and be fitted in
couples (first couple on IC-106 and IC-107, second on IC-108 and
IC-109).
All SRAM packages must be of the same type and size:
• 2
×
128 kbyte (1 Mbit) = 256 kbyte (2 Mbit)
• 4
×
128 kbyte (1 Mbit) = 512 kbyte (4 Mbit)
• 2
×
512 kbyte (4 Mbit) = 1.024 kbyte (8 Mbit)
• 4
×
512 kbyte (4 Mbit) = 2.048 kbyte (16 Mbit)
The size of the SRAM's is automatically defined by the printer.
The RAM memory is battery backed-up to avoid loss of data when
the printer is turned off or if the power fails. The NiCd-accumulator
is automatically recharged when the power is on. After having
installed the printer, leave the power on overnight to allow the
battery to become fully recharged. If the printer is kept turned on
less than full working hours, it is recommended to leave the power
on overnight at least once a week. Do not leave the printer off for
several weeks (e.g. during holidays) without having made a full
memory backup on a computer disk.
IC-20
The optional real-time clock circuit (RTC) contains a clock/
calendar with battery backup. When an RTC is fitted on IC-20, the
time and date do not have to be set manually each time the printer
is started. (See
TIME$
and
DATE$
in the UBI Fingerprint manuals
or in the UBI Direct Protocol Programmer's Guide).
When installing an RTC, be careful to fit it with the semi-circular
marking pointing upward, as seen when the CPU board is fitted in
the printer. Because of the risk of short-circuits, do not use any
conductive tools when fitting or removing the RTC.
FY-300
The CPU board contains components for transforming the mains
current into the various voltages required by the logics and the
printhead. The CPU board is protected by a fuse situated at the lower
left corner of the board.
Never replace a blown fuse without having found and remedied the
fault, that caused it to blow. That usually requires the assistance of
a skilled service technician.
WARNING!
The semicircular “front” marking of
each package should face upward as
seen when the CPU board is fitted
in the printer.
If a RAM package is fitted upside
down, the recharging of the CPU
board's battery backup could be
damaged. This will eventually cause
memory loss.
1
/. SRAM is an abbreviation for Static
Random Access Memory.
