7.2.5 Multi Media Controller section
Required equipment:
Multimeter
, Display terminal type
Digital
VT100 or equivalent
Digital oscilloscope
Analog oscilloscope
Timer/counter
7.2.5.1 Supply voltages
Check if the following voltages are present at
connector
1001
pin1
,2,3
pin4
pin5
pin6,7,8
: +5
V
±5%
:
-5
V±
5%
: +25
V±
5%
:GROUND
,
7.2.5.2 Clock signals:
Carry out measurements just after hardware reset.
This
is
done each time after pressing the OPEN/CLOSE
, button
or
after power-on.
System clock
30.0000
MHz±
1500
Hz
(PAL)
30.2098 MHz ± 600 Hz NTSC)
This system clock must be present
at
the following points:
IC7201 pin 30
IC7304 pin
80
IC7125 pin 115
At
IC
7201
pin 29 Clock divided
by
two must be present:
15.0000 MHz (=30.000: 2).
15.1049 MHz (NTSC)
Al IC7201 pin 69 the UART clock of 68070 must be present :
Frequency 4.9152
MHz±
250 Hz
At IC7206 pin 39 clock of '68HC05' must be present :
Frequency 4.000
MHz±
100
Hz
At IC7301 pin
94
the clock
of
the CDIC must me present:
Frequency 22.5792
MHz±
1100 Hz.
At
IC7306 pin 16 the DSP clock must
be
present
:
Frequency 7.5264MHz ± 380 Hz
7.2.5.31
2
S interface:
FILTERN :
av
DAAB
CLAB
WSAB
DEEM
: frequency 2.8224 MHz(only for CD-DA)
: frequency
44.1
KHz (only for CD-DA)
: 0V (only for CD-DA and only if de-emphasis
track is played)
7.2.5.4 Reset circuitry:
Press the OPEN/CLOSE button at front panel and measure
the 'RESETCD' time (low!). This 'low' time must be 140 ms
± 20
ms.
Also measure the RESETCD time(low!) if the
button is released. The signal RESETCD must be low for
140 ms
±20
ms.
IC7201 pin
28
RESETN; low time
=
250
ms±
20 ms
PCS 67 667
7.2.5.5 Check of microprocessor 68070.
Check after power on:
IC7201, pin 27
(=
HAL TN)
=
high (+5V)
IC7201, pin 28 (=RESETN)
=
high (+5V)
IC7201, pin 24 (=DTACKN)
=
changing high/low
IC7201, pin
26
(=BERAN)
= high (+5V)
7 .2.5.6 Low level test
Purpose is to test the hardware with software.
Connect a terminal, or SeNice PCB
to
the UART of micro-
processor 68070 via connector at rear side port 2
(=
BU-2).
How to start the low level test see section 5.2.
Settings of the terminal:
Baudrate : 9600
start bit : 1
data bists : 8
stop bits : 0
no
parity/ no handshake
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