UBI EasyCoder 601 XP – Service Manual Ed. 1
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Chapter 15 CPU Board
DRAM Memory (P23–P24)
The DRAM memory (Dynamic Random Access Memory) is the
printer's temporary memory (device "tmp:"). It will lose its content
when the power is turned off or at a power failure. Thus, it should
only be used for data that can easily be recreated or that is only
relevant for one power-on cycle. It is much faster than the flash
memory. Therefore, at start up the kernel is copied from the Flash
memory to the DRAM, where the various UBI Fingerprint instruc-
tions are executed.
The DRAM is also used for the font cache and various buffers. The
remainder is used for the two print image buffers where the bitmap
patterns are stored prior to printing. One buffer is used for the label
that is being printed, while the other receives the bitmap for next
label as the UBI Fingerprint instructions are processed. By switch-
ing between the buffers, batch printing without stopping between
labels can be achieved.
There are two sockets for DRAM SIMMs on the CPU board. A
DRAM SIMM must always be installed in socket P23 (DRAM0).
As standard, one 4 Mbyte DRAM SIMM is fitted. The space
available for the two image buffers gives a maximum label length
of approximately 300 mm (11.8") regardless of print width.
The size of the buffers depends on two factors:
• Number of physical dots on the printhead (regardless of “Media;
Width” and “Media; X-start” setup)
• Present “Media; Length” setup value in dots
Calculate the buffer size according to this formula:
(No of dots / 8 + 4) x (Media length in dots) = Buffer size in bytes
(Buffer size in bytes) / 1024 = Buffer size in kbytes
Buffer size in kbytes x 2 = Memory requirement in kbytes
Example:
The number of dots on the printhead is 1984
The Media; Length is set to 1800 dots (150 mm)
[[(1984 / 8) + 4) x (1800)] / 1024] x 2 = 886 kbyte total
If a larger print area is required, the DRAM memory can be
expanded with a second DRAM SIMM in socket DRAM1-2.
Technically, the CPU board allows up to 40 Mb of DRAM, but
presently only 4 Mbyte SIMMs are kept in stock. Approved DRAM
SIMMs can only be ordered from Intermec.
Electronic Key Circuit (P34)
The Dallas touch memory key in P34 contains the real-time clock
(RTC) oscillator and a system key, that is required to run the stepper
motors. If such a key is not fitted in P34, the printer cannot print, but
will otherwise work as normal. The key has a built-in battery
backup with a life of at least 10 years. When the printer is on, the
circuit is power supplied via the CPU board and will not consume
any power from the battery. The circuit also contains 4 kbit (500
bytes) of battery backed-up memory for the devices "lock:" and
"storage:".
15.2 Circuits and
Straps,
cont'd.
CAUTION!
The Electronic Key Circuit (P34) contains an
integrated lithium battery.
Replace only with original
Electronic Key Circuits from Intermec.
Dispose of used Electronic Key Circuits
according to local regulations for lithium
batteries.
