Loewe Q2500B Serviceanleitung Seite 186

Technology of Q 2500 colour TV set
range device the various functions are sup-
ported by an LCD display.
An 84 C 122 Philips microprocessor is used in
the remote control for the Q 2500 chassis
(Control 10 for Loewe Systems and Control
150 for Loewe.). This is an 8 bit standalone
microcontroller, especially designed for use in
infrared remote controls. It has very little ex-
ternal wiring and is able to control the trans-
mitter diode directly via an amplifying transis-
7
UB
osz / 30 f
WDT
6
5
T1
Battery
check
20
VSS
Document Q 2500
Internal circuit 84C122
ROM ROM
1k x 8 32 byte
I 101
PCA84C122A
Y01 Y03 Y05 Y07
Y00 Y02 Y04 Y06 X10
tor. The modulator is incorporated into the IC.
The processor is equipped with Loewe spe-
cific software, which is mask programmed. To
operate the Q 2500 chassis, commands are
issued as RC 5 code, level 0.
The operating commands are formed on the
transmitter keyboard by linking a Y input (Y4
Y7) with an X input (X10 X17).
T
TO/INT
X11 X13 X15 X17
X12 X14 X16
63
9
Oscillator
8
Hardware
Modulator
21
Output
Driver
TO/INT
© Loewe ProCollege
X111
4,3MHz
RSIG