Oki OKIPAGE6w Programming manual

All specifications are subject to change without notice.
OKIPAGE6w
LED Page Printer
Troubleshooting Manual
with Component Parts List
(OEL)

CONTENTS
1. OUTLINE.....................................................................................................1
2. TOOLS........................................................................................................1
3. CIRCUIT DESCRIPTION............................................................................2
3.1 Outline.....................................................................................................................2
3.2 CPU and Memory....................................................................................................4
3.3 Reset Control...........................................................................................................6
6.1 HUK PCB ............................................................................................................
............................................................................................................
............................................................................................................
6.2 P2H PCB 37
41
46
6.3 P6L PCB
3.4 EEPROM Control.....................................................................................................7
3.5 Centronics Parallel Interface....................................................................................8
3.6 Front Operator Panel...............................................................................................9
3.7 LED Head Control.................................................................................................10
3.8 Motor and clutch control........................................................................................12
3.9 Fuser Temperature Control....................................................................................14
3.10Sensor Control.......................................................................................................17
3.11Cover Open...........................................................................................................18
3.12Power Supply Part.................................................................................................19
4. TROUBLESHOOTING..............................................................................21
4.1 Troubleshooting Table............................................................................................21
4.2 Troubleshooting Flowchart.....................................................................................23
5. CIRCUIT DIAGRAM..................................................................................27
6. COMPONENT PARTS LIST AND LAYOUT.............................................. 36

- 1 -
1. OUTLINE
ThismanualhasbeenwrittentoprovideguidancefortroubleshootingoftheOKIPAGE6wPrinter
(primarilyforits printedcircuitboards), onanassumption thatthereader isknowledgeableof the
printer. Read the maintenance manual for this printer if necessary.
Note:
1. High voltage power supply board and power supply unit containing a high voltage power
supply is dangerous. From the viewpoint of the safety standards, the local repairing of a
defective board is not allowed. Thus, the objects to be locally repaired as a result of
troubleshooting are switches.
2. TOOLS
For troubleshooting the printer, the tools listed below may be needed in addition to general
maintenance tools.
Tool Remarks
Oscilloscope Frequency response 100 MHz or higher
Soldering iron A slender tip type, 15-20 watts

- 2 -
3. CIRCUIT DESCRIPTION
3.1 Outline
The circuit of OKIPAGE6w consists of a main control board, a main high voltage power supply
board,a syb-high voltage power supply board and a power supply unit. The block diagram is
shown in Fig. 3-1. The main control board controls the reception and transmission of data with
a host I/f and processes command analysis, bit image development, raster buffer read. It also
controls the engine and high voltage outputs.
(1)Reception and transmission control
The main control board has one parallel I/F port which is compliant to the IEEE 1284
specification.
Aninterfacetaskstores alldatareceivedfromthe hostintoareceivebuffer first, andreturns
the printer status upon request of the host.
(2)Command analysis processing
The OKIPAGE6w printer has the following emulation mode.
Hiper-W: OKI original
Anedittaskfetchesdatafromthereceivebuffer,analizescommands,andsetsI/Oregisters.
(3)Raster data processing
ThedecompressioncircuitintheCPUexpandsthecompresseddataandstoresthedatainto
the raster buffer.
(4)Raster data transfer
TheLEDheadcontrolcircuitintheCPU sendsthedatastoredintherasterbuffertotheLED
head.
(5)High voltage control (main, sub)
The high voltage control circuit in the CPU.
Thehighvoltagepowersupplyboardgenerateshighvoltageoutputs,andhavesensors,LEDfor
display.
The power supply unit generates +26VDC output, +5DC output.

- 3 -
Figure 3-1 OKIPAGE6w Block Diagram
DRAM
512kB
CPU
(nX8)
PCB H63-ONLY DRAM
1M x 4
Serial I/F
Parallel
I/F DRAM Bus
(Data : 4)
(Address : 11)
Internal
MASK ROM
62KB
High Voltage Power Unit
P6L
High Voltage Power Unit
P2H
EEPROM
1kb
Motor Driver
MTD2005F
OSC
16MHz HC125
RST
CN10CN1
ID Unit
CN7
Motor
HEAD1CN8
PLUNGER LED HEAD
CN2
0VP0V
0V5V
+5V+26V
LS07
CN4
Power Supply Unit

- 4 -
3.2 CPU and Memory
(1)CPU (MSM65917)
CPU core nX-8
CPU clock 16 MHz
Data bus width External 8 bits, Internal 8 bits
(2)Program ROM
ROM capacity 64k-bytes
ROM type 512 kbits (64k x 8 bits)
Access time 90 nsec
(3)Resident RAM
RAM capacity 512k bytes (1M x 4 bits D-RAM one piece)
RAM type 4M bits (1M x 4 bits)
Access time 60 ns

- 5 -
Figure 3-2 Block Diagram of CPU & Memory in OKIPAGE6w
CPU
IC 6
ALE
RDN
ROCS
DA10
DWR
CAS
RAS0
RAS1
RAS2
LS373
IC3
IC2
EPROM
(64k x 8 bits)
IC11
DRAM
(1M x 4 bits)
AD00 to AD07 A00 to A07
A08 to A15
DD00 to DD03
DA00 to DA09
Main Control Board

- 6 -
3.3 Reset Control
When power is turned on, RST-N signal is generated by IC5.
Power OFF
Power ON
+5V
RST-N
CPU
63
1
2
3
IC5
IC6
+5V+5V
RSTN

- 7 -
Instruction Start bit Operation Address Data
code
Read (READ) 1 10 A5 to A0
Write Enabled (WEN) 1 00 11XXXX
Write (WRITE) 1 01 A5 to A0 D15 to D0
Write All Address (WRAL) 1 00 01XXXX D15 to D0
Write Disabled (WDS) 1 00 00XXXX
Erase 1 11 A5 to A0
Chip Erasable (ERAL) 1 00 10XXXX
3.4 EEPROM Control
The BR93LC46A on the main control board is an electrical erasable/programmable ROM of 64-
bit x 16-bit configuration. Data input to and output from the ROM are bidirectionally transferred
inunitsof16bitsthroughI/Oport(EEPRMDT-P)inserialtransmissionsynchronizedwithaclock
signal from the CPU.
The EEPROM operates in the following instruction modes.
Write cycle timing (WRITE)
Read cycle timing (READ)
CPU
EEPRMDT-P IC4
IC6
EEPRMCS-P
EEPRMCLK-P
3
39
38
37 2
4
1
DI DO
CS
SK
EEPROM
CS
SK
DI
DO HIGH-Z
1 2 4 9 10 25
Min. 450 ns
10 1
A5 A4 A1 A0 D15 D14 D1 D0
STATUS
BUSY READY
Max. 500 ns
Max. 10 ms
HIGH-Z
12
110
4910
A5 A4 A1 A0
25 26
D15 D14 D1 D00 D15 D14
CS
SK
DI
DO

- 8 -
3.5 Parallel Interface
Parallel data is received from a host system via parallel interface which is compliant to the
IEEE1284 specification.
Compatible mode
TheCPUsets aBUSY-Psignal toONatthesametimewhenitreadsthe paralleldata(PDATA1-
P to PDATA 8-P) from the parallel port at the fall of PSTB-N signal. Furthermore, it makes the
store processing of received data into a receive buffer terminate within a certain fixed time and
outputs an ACK-N signal, setting the BUSY-P signal to OFF.
CPU
CN4
IC6 65 to 68, 71 to 74
PDATA1-P to PDATA8-P
PSTB-N
BUSY-P
ACK-N
PE-P
FAULT-N
SEL-P
IPRIME-N
SELIN-N
AUTOFD-N
64
78
77
79
80
81
82
83
84
2 to 9
1
11
10
12
13
32
31
36
DATA8-P
to
DATA1-P
STB-N
BUSY-P
ACK-N
PE-P
FAULT-N
IPRIME-N
SEL-P
SELIN-N
AUTOFEED-N
14
+5V
IC7
+5V or High level 18
PARALLEL DATA
(DATA BITs 1 to 8)
DATA STROBE
BUSY
ACKNOWLEDGE
0.5 µs min. 0.5 µs min.
0.5 µs min.
0.5 µs min.
0.5 µs max. 0 min.
0 min.
0 min.
0.5 µs to 10 µs
0 min.

- 9 -
3.6 LED Lamp Control
ThereisanLEDlamponthehighvoltagepowersupplyboardwhichisconnectedtoandcontroled
by the CPU on the main control board.
The light from the LED lamp can be seen on the Lens Cover through the LED Lens.
CPU
main control board high voltage power supply board
CN1
IC6
41 LED-P
CN1

- 10 -
3.7 LED Head Control
An LED correcting head, which is capable of correcting the illumination of the LED for each dot,
is being used in this printer. LED illumination correction function of 16 steps is carried out by using
an EEPROM which is installed in the LSI that maintains the LED illumination correction values,
and an LED correction drivers (MSM6731BWAF or MSM6732BWAF) together as a pair.
The LED correcting head consists of the correction control LSI (MSM6730WAF), LED drivers
(MSM6731BWAF or MSM6732BWAF), and an LED array.
STRB0-N
STRB1-N
STRB2-N
STRB3-N
LOADI
CLOCKI
DATAI0
DATAI1
MSM6730
WAF
EEPROM
Correction
Values
LED LED LED LED LED LED LED
LED Driver
MSM6732BWAF
LED Driver
MSM6732BWAF
LED Driver
MSM6731BWAF
LED Driver
MSM6731BWAF
LED Array
Printing and correction data combined sign
Correction data signal line
From
CPU

- 11 -
VLD-P
VSTB4-N
VSTB3-N
VSTB2-N
VSTB1-N
VDT-P
VDT-P
VCLK-P
VCLK-P
VDT-P
0.78 msec
8 bits
8 bits 4992 bits
0.3 µs
Page
synchronous
signal*
Line
synchronous
signal*
* CPU internal signal

- 12 -
3.8 Motor and clutch control
Theelectromagneticclutchisdriven byacontrolsignalfrom theCPUand thedrivecircuitshown
below.
The main motor is driven by the control signals from the CPU and the driver IC.
(1) Main motor
M
CPU
DMP1
DMON
CN7
+5V
+5V
+5V
+5V
23 22 28 15 10 21 20TAB5
+5V
+5V +26V
ENA A
SW1 SW3
SW4SW2
SW1 SW3
SW4SW2
Out1
IC10 Out2 Out3
Main Motor
Current
Sensor
Current
Sensor
ALARM
Out4Vmm A Vmm B
ENA B
DECAY
PHASE A PHASE B
0V
0V
0V
0V 0VP
Electromagnetic clutch
0V
19
26
25
18
27
96
97
98
99
37 1 1412 24
16
17
8
+26V OPEN
DMP2
RMON
CN8
+5V
OSC
GATE CIRCUIT
GATE CIRCUIT
BRUNK Q-
+
-
+
R
SRQ S
Vref A Vref B
Vs A Vs BRs A Rs BLG A PG LG B
To Out3, 4Logic
Signal of
DECACY
120°C 140°C
Operation at normal speed: T0 to T3 = 0.781 ms
DMON-P
DMPH1-P
DMPH2-P T0 T1 T2 T3
Rotation Forward rotation Reverse rotationStop

- 13 -
(2) Motor drive control
Time T0 to T3 determines the motor speed, while the phase different direction between
phase signals DMPH1-P and DMPH2-P determines the rotation direction. DMON-P signal
controlamotorcoilcurrent. Accordingtothepolarityofthephasesignal,thecoilcurrentflow
as follows:
1) +26V →SW1 →motor coil →SW4 →resistor →earth, or,
2) +26V →SW3 →motor coil →SW2 →resistor →earth
The drop voltage across the resistor is input to comparator, where it is compared with a
reference voltage. If an overcurrent flows, a limiter operates to maintain it within a certain
fixed current.
(3) Electromagnetic clutch control
Mechanical operation mode is switched by the combination of the clutch status and the
direction of motor rotation.
clutch status
off
off
on
on
rotation direction
Forward
Reverse
Forward
Reverse
operation mode
cleaning
Hopping from manual
feed slot
illegal operation
Hopping from tray

- 14 -
3.9 Fuser Temperature Control
The temperature change in a heat controller is converted into the electric potential TEMP
corresponding to the change in the resistance value of a thermistor, and the resultant potential
is fed back to the control circuit. The CPU performs ON/OFF control of the HEATON-P signal to
keep the heat roller temperature constant in accordance with the state at which the thermistor
voltage (TEMP) is read into directly by the AD converter of the CPU.
When the paper thickness is set on the menu of the host, the temperature is adjusted to the
targeted thickness accordingly.
Main Control Board High voltage power
supply board
+5V
CPU
ACIN
Ther-
mistor
Heater
Heat Roller
Thermostat
THCHK-N
HEATON-P
HEATON-N
27
57
IC20
+5V +5V
+
-
6
31
IC20
+
-
2
34
85
TEMP AI4
(A/D)
Power supply unit
+5V

- 15 -
Flowchart of Thermistor Circuit Check
HEATER OFF
Short check timer(t16)set
Temperature > Tn
Thermistor
error check timer (t2)
within time
Thermistor
disconnection check timer
(t35) within time
START
To constant
temperature control
End
Heater On
Yes
Yes
Yes
Yes
Yes
No
No
No
No
No
No
No
Yes
Yes
Fuser error
Fuser error
End
End
Thermistor gain change
THCHK-N"0" "Z"
Thermistor
disconnection error
Thermistor short error
t2 =
t16 =
t35 =
90 sec
520 msec
10 sec
Thermistor error check
timer (t2) set
Thermistor disconnection
check timer (t35) set
Time-out ?
Short error TEMP ?
End
A/D value changed?
A/D value more than
20H?

- 16 -
Temperature
Controlled
Temperature
T
HEATER ON
OFF
Time
Temperature table
THERMCMP-N
O
Z
Heater control mode
Normal operation
Fuser Error Check
T
135˚C:
140˚C:
145˚C:
150˚C:
155˚C:
Paper Thickness
light
medium light
medium
medium heavy
heavy

- 17 -
3.10 Sensor Control
The CPU supervises the state of each sensor every 40 ms.
OFF
TNRSNS-N
CN1 CN1
PSIN-N
PSOUT-N
WRSNS-N
CPU
+5V
PS1
PS2
PS3
PS4
ON
TransparentShield
Sensor
signal
47
44
46
48
+5V
+5V
+5V
+5V
Main Control Board High Voltage Power Supply Board

- 18 -
3.11 Cover Open
Whenthe coverisopened, acover openmicroswitch isopened. This makesaCVOPN-N signal
low,thereby theCPUdetects thatcover isopen. Furthermore,openingthecover stopsapplying
a+5Vpower to the highvoltage power supply part,resultingin stopping allhighvoltage outputs.
CPU
IC6
CVOPN-N
Cover
Open
Microswitch
+5V
+5V
0V
Cover close Cover open
High
Voltage
Power
Supply
Part
High
voltage
output
45
CVOPN-N
Main Control Board
CN1 CN1
High Voltage Power Supply Board
+5V