Block Diagram - Kenwood DMF-9020 Service Manual

Pin No. Port Name I/O
21 CS (SRAM) O SRAM control. chip select
22 WR – SRAM control. write strobe signal output
23 RD – SRAM control. read strobe signal output
24-28 NC O no use
29-35 A14-8 – SRAM control. address bus
36-42 AD7-1 – SRAM control. address/data bus
43 AD0 – SRAM control. address/data bus
44 ASTB – SRAM control. address strobe signal output
45 VSS – Microprocessor GND
46 TEST – Microprocessor TEST
47,48 NC O no use
49 MENA O Mechanism-microprocessor. enable
50 MRXD – Mechanism-microprocessor. data in line (UART)
51 MTXD O Mechanism-microprocessor. data out line (UART)
52-54 NC O no use
55 VDD – Microprocessor power supply (+)
56-61 NC I no use
62 CTR_JIS I Cyber titler. for JIS code
63 TXT_JIS – CD TEXT. for JIS code
64 AVDD – A/D power supply
65 AVref1 – A/D reference voltage input port (+5V)
66 AVSS – A/D GND
67,68 NC O no use
69 AVref2 – D/A reference voltage input port (+5V)
70 AVref3 – A/D reference voltage input port (GND)
71,72 NC I no use
73 DQSY – Text data read permit
74-76 NC I no use
77 CLOCK I IBM key board I/F clock line
78 SRDT I Text data read line
79 TRXD I Cyber titler. data in line (UART)
80 TTXD O Cyber titler. data out line (UART)
3. D/A converter : AD1855 (X25 : IC7)
Block diagram (No. of : pin No.)
19
AD1855
25 ~ 27 ATTEN/ 8x
MUTE INTERPOLATOR
16-/18-/20-/24-BIT
SERIAL DATA
DIGITAL
INTERFACE
DATA INPUT ATTEN/ 8x
INTERPOLATOR
MUTE
SERIAL
MODE
20 , 21
ANALOG
DIGITAL
GND RD/RST
GND
11 , 15 24
1
Description
H : POWER DOWN
L : POWER DOWN
H : JIS
H : JIS
L : interrupt
L : interrupt
28
3 ~ 5 14 2 10
CONTROL DATA DIGITAL
CLOCK 96/48Fs
INPUT SUPPLY IN CLOCK
SERIAL CONTROL VOLTAGE CLOCK
INTERFACE REFERENCE CIRCUIT
OUTPUT
MULTIBIT SIGMA-
DAC
DELTA MODULATOR BUFFER
OUTPUT
MULTIBIT SIGMA-
DAC
BUFFER
DELTA MODULATOR
ZERO
ANALOG
MUTE DE-EMPHASIS
FLAG
SUPPLY
23 22
9 18 8 ,
4. Test mode of the unit
4-1 Setting of the test mode
While pressing the [REC/INPUT] key, plug the AC power
cord into the AC wall outlet.
4-2 Contents of the test mode
Choose the 3 mode by TIMER switch position below.
TIMER SW Mode
(1) REC INSPECTION
(2) PLAY ERROR RATE
OFF NONE
NONE means none mode.
(1) [ INSPECTION ] mode
• ENGLISH display (2secs)
• " NIAGARA TEST " display
Dot : Niagara
Segment : All lighting
• Push a key, then cancel " NIAGARA TEST "
6
384/256
X2MCLK 7
12 , 13 16 17 , ,
ANALOG
OUTPUTS
• Function of the key
Key Mode
REC/INPUT KEY-TEST
EDIT NIAGARA TEST
TITLE INPUT None all lighting
Display [ KEY 028 ] into the KEY-TEST mode.
Push a key, then display [ KEY ] .
(2) [ ERROR RATE ] mode
• Function of the key
Key Function
PLAY CPLAY (MID)
REC CREC (MID)
STOP CPLAY, CREC
STOP
(2time push) ERROR RATE
5. Microprocessor reset
The microprocessor can be initialized while pressing the
[EJECT] key, plug the AC power cord into the AC wall
outlet.
6. Mechanism test mode
Refer to 1050MD/DM-5090/MD-9090 service manual (B51-
5387-00), if you see this test mode.