Intermec EasyCoder 501XP, Руководство по обслуживанию

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Intermec EasyCoder 501 XP & 601 XP – Service Manual
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Chapter 2 Front and Keyboard
The keyboard/display assy. consists of a plate with two brackets,
a self-adhesive membrane switch keyboard, an self-adhesive over-
lay, and a console pcb. The membrane switch keyboard is con-
nected to P2 on the console pcb. via a semi-transparent cable
running through a slot in the plate.
Keyboard Overlay
The keyboard overlay is self-adhesive with a non-permanent adhe-
sive to allow easy replacement. Custom-made overlays could also
be printed and used to replace the standard overlays for custom-
ized applications or in areas, where the English text is not accept-
able. Pulling away an overlay and replacing it with another is a
simple operation that the customer easily can perform himself. Use
isopropyl alcohol to remove any adhesive residue.
Keyboard
The keyboard is of membrane switch type and is glued to the key-
board plate. There are 54 switches, but only 23 of these are used.
One switch is a Shift key, that provides a dual functionality to each
of the other keys. A resistor ladder gives different voltages from
each line and column on the keyboard so the slave processor on the
console pcb can decode signals from the various switches (keys)
by means of an A/D converter.
Keyboard Plate
The keyboard plate keeps the assembly together and to affi x it in
the cavity of the front moulding. There are one slot for the display
and another for the cable running from the membrane-switch key-
board to the console pcb. Two brackets at the lower edge are used
to connect the plate to the front moulding using two 2 mm hexagon
grub screws.
2.2 Keyboard/Display,
cont.
Console pcb.
Keyboard Plate
Membrane-Switch Keyboard
Overlay