HP 3562A, Руководство по обслуживанию

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MODE L 3562A
C I RC U I T D E SCRI PT I O N S
Internal Signal Descriptions
ClRPG L
D I R1
DIR2
E N A B LE D L
EPO t o EP7
KACKL
KAS
Il D n f. .... Il D '7
. " .... '" I. " I' Ll J
CLEAR ROTAT I O N P U LSE G E N E RATOR (RPG)
Active Low
Output of the keyboard device decoder. This signal clears the turn
and interrupt latches.
DI RECTION of ROTAT ION of RPG1
Direction latch 1 send D I R1 to the keyboard processor to i ndicate
which direction the m arker RPG has been rotated .
DI RECTION of ROTAT ION of RPG2
Direction latch 2 sends DI R2 to the keyboard processor to indicate
which d irection the parameter RPG has been rotated .
ENABLED PARAM ETER
Active Low
The LEDs latch 1 sets ENABLE D L low to l ight the E nable LED and
activate Turn Latch 2.
E PROMO to EPROM7
The keyboard E P ROM sends instructions to the keyboard processor
using these lines.
KEY BOARD ACKNOW L E D G E
Active Low
Signal from the keyboard device decoder to clock DTACK L out to the
A2 System CPU.
KEYBOARD ADDRESS STRO BE
Signal from the keyboard processor indicati ng addresses KAB to KA1 2
are val id.
V C V D r\ A D n D I I C 1 I !.. I !: C {\ L L
_ _
.
.
_ L "7
'"\' L ' v '-' '' ' ' u v u .:> L I I 'I L: ':> U
l I l I U U g l 1
I
Keyboard data l ines the keyboard processor uses for input and output.
• " "--"""" �-. m_" ..... processor
to-
-
circu it when there
is valid d ata on K BO to KB7.
KRD
KROM L
KEYBOARD READ/WRITE
This signal determines whether the keyboard processor is read ing or
writi ng on data l i nes K BO to KB7. The keyboard control ci rcu itry also
uses KRD to set up i nput and output operations for the keyboard.
KEYBOARD ROM
Active Low
This signal from the keyboard device decoder enab les the instru ction
ROM l i nes E PO to E P7.
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