UX-485TH
FO-885TH
3. Operational description
CHAPTER 5. CIRCUIT DESCRIPTION
Operational descriptions are given below:
[1] Circuit descriptionYTransmission operation
When a document is loaded in standby mode, the state of the docu-
ment sensor is sensed via the 1 chip fax engine (SCE114V). If the
1. General description
sensor signal was on, the motor is started to bring the document into
The compact design of the control PWB is obtained by using CONEXANTthe standby position. With depression of the START key in the off-
fax engine in the main control section and high density printing hook state, transmission takes place.of sur-
face mounting parts. Each PWB is independent according to its Then, the procedure is sent out from the modem and the motor isfunction
as shown in Fig. 1.rotated to move the document down to the scan line. In the scan
processor, the signal scanned by the CIS is sent to the internal im-
2. PWB configurationage processor and the AD converter to convert the analog signal into
binary data. This binary data is transferred from the scan processor
to the image buffer within the RAM and encoded and stored in the
transmit buffer of the RAM. The data is then converted from parallel
TEL/LIUto serial form by the modem where the serial data is modulated and
PWBsent onto the line.
CIS
YReceive operation
CONTROLThere are two ways of starting reception, manual and automatic.
PWB
LCDDepression of the START key in the off-hook mode in the case of
PWBmanual receive mode, or CI signal detection by the LIU in the auto-
matic receive mode.
POWER
SUPPLYFirst, the SCE114V controls the procedure signals from the modem
PWB
to be ready to receive data. When the program goes into phase C,
PANEL
AC CORDthe serial data from the modem is converted to parallel form in the
PWB
modem interface of the 1 chip fax engine (SCE114V) which is stored
MOTORin the receive buffer of the RAM. The data in the receive buffer is
decoded software-wise to reproduce it as binary image data in the
image buffer. The data is DMA transferred to the recording processor
within the SCE114V which is then converted from parallel to serial
Fig. 1form to be sent to the thermal head. The data is printed line by line by
1) Control PWBthe SCE114V which is assigned to control the motor rotation and
strobe signal.
The control PWB controls peripheral PWBs, mechanical parts, trans-
mission, and performs overall control of the unit.YCopy operation
This machine employs a 1-chip modem (SCE114V) which is installed onTo make a copy on this facsimile, the COPY key is pressed when the
the control PWB.machine is in stand-by with a document on the document table and
the telephone set is in the on-hook state.
2) TEL/LIU PWBFirst, depression of the COPY key advances the document to the
This PWB controls connection of the telephone line to the unit.scan line. Similar to the transmitting operation, the image signal from
the CIS is converted to a binary signal in the DMA mode via the 1
chip fax engine (SCE114V) which is then sent to the image buffer of
3) Power supply PWB
the RAM. Next, the data is transferred to the recording processor in
This PWB provides voltages of +5V and +24V to the other PWBs.the DMA mode to send the image data to the thermal head which is
printed line by line. The copying takes place as the operation is re-
peated.
4) Panel PWB
The panel PWB allows input of the operation keys.
5) LCD PWB
This PWB controls the LCD display.
5 � 1 |
ACEC
