Circuit Description - Kenwood KD-9X Service Manual

D-3N/9X6
CIRCUIT DESCRIPTION
NEW PARTS DESCRIPTION
1. Mechanism Control IC (LM6405-042)
'In the KD-9X the movement of the
PORT
. ; Plea CS
tonearm is controlled by a micro- - I
processor. This microprocessor is an N- = 64x 4-bit 8 ro ete
channel E/D MOS 4-bit microprocessor py, cS RAM 5 tom
LSI in a 42-pin dual-in-line package. :
The block diagram of the microprocessor x at
is shown in fig. 1. PGo-3 core ¢
¥ G = |
Cy 4
c STACK 2
F
|
PLAg-7
EL Timer counter |
POR
PEo-s Co : T
PORT PORT PORT PORT —
D Cc B A O INT
oe oY 08
—~-O Xtal
PDo-3 PCo-3 PBo-3 PAo.3 =O EXtal
~*OVpp
AC : Accumulator *OVss
: : : : Cc : Carry FF
ALU : Arithmatic and logic unit :
DP : Data pointer : Temporary carry FF
P Program counter
PLA : Programmable logic array C g
Fig. 1 Block diagram of microprocessor (LM-6405-042)
Description of Pins
The input/output terminals are determined by the usage of
the microprocessor, and each input/output circuits will be se-
tected for them. In this microprocessor, the following input
or output circuits are selected.
pee eee
input only
ia
LE "LAY
jouurenty — /V/L"Toojoo|rul eu
Prouansoanu [7] pos hool V/V)
@ High threshold input gate (H) input only
Terminal
[>
@ High threshold input/open drain output (H.OD) input and
output
@ Open drain output (OD) output only
Terminal ~
@ Pulled-up output (PU) output only
Terminal —-