X-Y Plotter Description (Service Group H) - HP 3585A Service Manual

Model 3585A
6·30. x·y PLOTTER D ESCRIPTI O N (Service Group H)
The A62, X-Y Plotter, board provides the rear panel outputs for an X-Y Plotter. Y-axis in­
formation enters the board from the Digital Display Driver board (A63) . It is the latched on­
to the board and is then digital to analog converted . The analog signal is low passed filtered
and goes to the output .
X-axis information also enters the board from the Digital Display Driver board. It takes
four forms: UP X is a count up signal incrementing a 1 0-bit cascade counter and therefore
the X-axis plotter output . DWN X similarly decrements the counter. LOAD X loads the
counter causing an output that would move the pen to the far right . CLR X resets the
counter causing an output that would move the pen to the far left . The output of the counter
is converted to analog signal and is the low pass filtered.
A 6 2 B L O C K D I A G RA M
1 0
B I T
B I T
1 0
1 0
D A C
L A T C H
>
B I T
B I T
1 0
1 0
C O U N T E R
D A C
Figure 6· 1 8. X· Y Plotter Block Diagram
Scans by ARTEK MEDIA. =>
Circuit Functional Descriptions
B U F F E R
N O T E
5 C H E MA T 1 C DRAW 1 N G N U M B E R F O R
T H E A 6 2 B OARD 1 5 H A N D CAN
B E F O U N D 1N V O L U M E TWO .
P L O T T E R
X O U T
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