Panasonic KX FLB758RU User Manual

							8.5. MODEM SECTION
8.5.1. FUNCTION
The unit uses CODEC (IC609) and ASIC (IC604) that serves as an interface between the control section for FAX transmission
and reception and the telepho ne line. During a transmitting operation, the digital image signals are modulated and sent to the
telepho ne line.
During a receiving operation, the analog image signals which are received via the telepho ne line are demodulated and
converted into digital image signals. The communication format and procedures for FAX communication are standardized by
ITU-T. CODEC and ASIC has hardware which sends and detects all of the necessary signals for FAX communication .
It can be controlled by writing commands from the CPU (IC604: inside ASIC).
This CODEC and ASIC also sends DTMF signals, generates a call tone (from the speaker), and detects a busy tone and dial
tones.
Overview of Facsimile Communication Procedures (ITU-T Recommendation):
 1.  ON CCITT (International Telegraph and Telephone Consultative Committee)
The No. XIV Group of ITU-T, one of the four permanent organizations of the International Teleco mmunications Union (ITU),
investigates and make recommendatio ns on international standards for facsimiles.
 2.  Definition of Each Group
 
     · 
  
  Group I (G1)
Official A-4 size documents without using formats which reduce the band width of a signal are sent over telepho ne lines.
Determined in 1968.
Transmission for about 6 minutes at a scannin g line density of 3.85 lines/mm.
 
     · 
  
  Group II (G2)
Using reduction technology in the modulation/demodula tion format, an A-4 size document is sent at an official scannin g line
density of 3.85 lines/mm for about 3 minutes.
Method s to suppress redundancy are not used.
Determined in 1976.
 
     · 
  
  Group III (G3)
Method of suppressing redundancy in the image signal prior to modulation is used. An A-4 size document is sent within
about one minute.
Determined in 1980.
 
     · 
  
  Group IV (G4)
Transmission is via the data network. A method is provided for suppressing redundancy in signals prior to transmission, and
error-free reception of transmission is possible.
The scope of these facsimile applica tions is not limited simply to transmission of written statements. Through symbiotic
linkages with other communication methods, it can be expecte d to expand to include integrated services.
 3.  Facsimile Call Time Series
As shown in the followin g diagram, the facsimile call time series is divided into five phases.
Phase A : Call setting
Call setting can be manual/autom atic.
Phase B : Pre-message procedure
Phase B is a pre-processing procedure and sequence for confirming the status of the terminal, transmission route, etc., and for
terminal control. It implements terminal preparation status, determines and displays terminal constants, confirms
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							synchro nization status, etc. and prepares for transmission of facsimile messages.
Phase C: Message transmission
Phase C is the procedure for the transmitting facsimile messages.
Phase D : Post message procedure
Phase D is the procedure for confirming that the message is completed and received. For continuous transmission, phase B
or phase C is repeated for transmission.
Phase E : Call retrieval
Phase E is the procedure for call retrieval, that is for circuit disconn ection.
 4.  Concerning Transmission Time
Transmission Time
= Control Time+ Image Transmission Time+HoldTime
Transmission time consists of the followin g.
Control time: This is time at the start of transmission when the function s at the sending and receiving sides are confirmed, the
transmission mode is established, and transmission and reception are synchro nized.
Image transmission time: This is the time required for the transmission of document contents (image data). In general, this time is recorded in the
catalog, etc.
Hold time: This is the time required after the document contents have been sent to confirm that the document was actually sent, and
to check for telepho ne reservations and/or the existence of continuous transmission.
 5.  Facsimile Standards
ItemTelephone Network Facsimile
G3 Machine
Connection Control ModeTelephone Network Signal Mode
Terminal Control ModeT. 30 Binary
Facsimile Signal FormatDigital
Modulation ModePSK (V. 27 ter) or QAM (V. 29)
Transmission Speed300 bps (Control Signal)
2400, 4800, 7200, 9600, 12000, 14400 bps (FAX Signal)
Redundancy Compression
Process
(Coding Mode)1 dimension: MH Mode
2 dimension: MR Mode (K=2.4)
ResolutionMain Scan: 8 pel/mm
Sub Scan: 3.85, 7.7l/mm
Line Synchronization SignalEOL Signal
1 Line Transmission Time
[ms/line]Depends on the degree of data reduction.
Minimum Value: 10, 20
Can be recognized in 40ms.
 6. Explanation of Communication and Compression Technology
 a. G3 Communication Signals (T. 30 Binary Proces s)
For G3 Facsimile communication , this is the procedure for exchan ging control signals between the sending and receiving
machines both before and after transmission of image signals.
Control signals at 300 bps FSK are: 1850 Hz...0, 1650Hz...1.
An example of a binary process in G3 communication is shown below.
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							Explanation of Signals
Control signals are comprised mainly of 8-bit identific ation signals and the data signals added to them. Data signals are
added to DIS and DCS signals.
Signal.....DIS (Digital Identific ation Signal)
Identific ation Signal Format.....00000001
Function:
Notifies the capacity of the receiving unit. The added data signals are as follows.
Signal.....DCS (Digital Command Signal)
Identific ation Signal Format.....X1000001
Example
(Some models do not support the followin g items.):
Bit No.DIS/DTCDCS
1Transmitter --- T.2 operation
2Receiver --- T.2 operationReceiver --- T.2 operation
3T.2 IOC = 176T.2 IOC = 176
4Transmitter --- T.3 operation
5Receiver --- T.3 operationReceiver --- T.3 operation
6Reserved for future T.3 operation features
7Reserved for future T.3 operation features.
8Reserved for future T.3 operation features.
9Transmitter --- T.4 operation
10Receiver --- T.4 operationReceiver --- T.4 operation
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							Bit No.DIS/DTCDCS
11, 12, 13, 140, 0, 0, 0
0, 1, 0, 0
1, 0, 0, 0
1, 1, 0, 0
0, 0, 1, 0
0, 1, 1, 0
1, 0, 1, 0
1, 1, 1, 0
0, 0, 0, 1
0, 1, 0, 1
1, 0, 0, 1
1, 1, 0, 1
0, 0, 1, 1
0, 1, 1, 1
1, 0, 1, 1
1, 1, 1, 1Data signaling rate
V.27 ter fall back mode
V.27 ter
V.29
V.27 ter and V.29
Not used
Reserved
Not used
V.27 ter and V.29 and V.33
Not used
Reserved
Not used
V.27 ter and V.29 and V.33 and V.17
Not used
Reserved
Not used
ReservedData signaling rate
2400 bit/s, V.27 ter
4800 bit/s, V.27 ter
9600 bit/s, V.29
7200 bit/s, V.29
14400 bit/s, V.33
12000 bit/s, V.33
Reserved
Reserved
14400 bit/s, V.17
12000 bit/s, V.17
9600 bit/s, V.17
7200 bit/s, V.17
Reserved
Reserved
Reserved
Reserved
15R8 ×7.7 lines/mm and/or 200× 200 pels/25.4mmR8×7.7 lines/mm and/or 200× 200 pels/25.4mm
16Two-dimensional coding capabilityTwo-dimensional coding capability
17, 18
(0, 0)
(0, 1)
(1, 0)
(1, 1)Recording width capabilities
1728 picture elements along scan line length of
215 mm ± 1%
1728 picture elements along scan line length of
215 mm ± 1%
2048 picture elements along scan line length of
255 mm ± 1%
2432 picture elements along scan line length of
303 mm ± 1%
1728 picture elements along scan line length of
215 mm ± 1%
2048 picture elements along scan line length of
255 mm ± 1%
InvalidRecording width
1728 picture elements along scan line length of
215 mm ± 1%
2432 picture elements along scan line length of
303 mm ± 1%
2048 picture elements along scan line length of
255 mm ± 1%
Invalid
19, 20
(0, 0)
(0, 1)
(1, 0)
(1, 1)Maximum recording length capability
A4 (297 mm)
Unlimited
A4 (297 mm) and B4 (364 mm)
InvalidMaximum recording length
A4 (297 mm)
Unlimited
B4 (364 mm)
Invalid
21, 22, 23 (0,0,0)
(0,0,1)
(0,1,0)
(1,0,0)
(0,1,1)
(1,1,0)
(1,0,1)
(1,1,1)Minimum scan line time capability of the receiver
20 ms at 3.85 l/mm: T
7.7=T3.8540 ms at 3.85 l/mm: T7.7=T3.8510 ms at 3.85 l/mm: T7.7=T3.855 ms at 3.85 l/mm: T7.7=T3.8510 ms at 3.85 l/mm: T7.7=1/2T3.8520 ms at 3.85 l/mm: T7.7=1/2T3.8540 ms at 3.85 l/mm: T7.7=1/2T3.850 ms at 3.85 l/mm: T7.7=T3.85
Minimum scan line time
20 ms
40 ms
10 ms
5ms
0ms
24Extend fieldExtend field
252400 bit/s handshaking2400 bit/s handshaking
26Uncompressed modeUncompressed mode
27Error correction modeError correction mode
28Set to “0”.Frame size 0 = 256 octets 1 = 64 octets
29Error limiting modeError limiting mode
30Reserved for G4 capability on PSTNReserved for G4 capability on PSTN
31T.6 coding capabilityT.6 coding enabled
32Extend fieldExtend field
33
(0)
(1)Validity of bits 17, 18
Bits 17, 18 are valid
Bits 17, 18 are invalidRecording width
Recording width indicated by bits 17, 18
Recording width indicated by this field bit information
34Recording width capability 1216 picture elements along
scan line length of 151 ± mm 1%Middle 1216 elements of 1728 picture elements
35Recording width capability 864 picture elements along
scan line length of 107 ± mm 1%Middle 864 elements of 1728 picture elements
36Recording width capability 1728 picture elements along
scan line length of 151 ± mm 1%Invalid
37Recording width capability 1728 picture elements along
scan line length of 107 ± mm 1%Invalid
38Reserved for future recording width capability.
39Reserved for future recording width capability.
40Extend fieldExtend field
41R8 ×15.4 lines/mmR8 ×15.4 lines/mm
42300× 300 pels/25.4 mm300×300 pels/25.4 mm
43R16×15.4 lines/mm and/or 400× 400 pels/25.4 mmR16×15.4 lines/mm and/or 400× 400 pels/25.4 mm
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							Bit No.DIS/DTCDCS
44Inch based resolution preferredResolution type selection
“0”: neuritic based resolution
“1 ”: inch based resolution
45Metric based resolution preferredDon ’tcare
46Minimum scan line time capability for higher resolutions
“0 ”:T
15.4=T7.7“1”:T15.4=1/2T7.7
Don ’tcare
47Selective Polling capabilitySet to “0”.
48Extend fieldExtend field
Note 1 - Standa rd facsimile units conforming to T.2 must have the followin g capabil ity: Index of cooperation (IOC)=264.
Note 2 - Standa rd facsimile units conforming to T.3 must have the followin g capabil ity: Index of cooperation (IOC)=264.
Note 3 - Standa rd facsimile units conforming to T.4 must have the followin g capabil ity: Paper length=297 mm.
SignalIdentification Signal FormatFunction
Training 1———————A fixed pattern is transmitted to the receiving side at a speed
(2400 to 14400 bps) designated by DCS, and the receiving side
optimizes the automatic equalizer, etc., according to this signal.
TCF
(Training Check)———————Sends 0 continuously for 1.5 seconds at the same speed as the
training signal.
CFR
(Confirmation to Receive)X0100001Notifies the sending side that TCF has been properly received. If
TCF is not properly received, FTT (Failure To Train) X0100010 is
relayed to the sender. The sender then reduces the transmission
speed by one stage and initiates training once again.
Training 2———————Used for reconfirming the receiving side like training 1.
Image SignalRefer to the next page.———————
RTC
(Return to Control)———————Sends 12 bits (0...01 ×6 times) to the receiver at the same speed
as the image signal and notifies completion of transmission of the
first sheet.
EOP
(End of Procedure)X1110100End of one communication
MCF
(Message Confirmation)X0110001End of 1 page reception
DCN
(Disconnect)X1011111Phase E starts.
MPS
(Multi-Page Signal)X1110010Completion of transmission of 1 page. If there are still more
documents to be sent, they are output instead of EOP. After MCF
reception, the sender transmits an image signal of the second
sheet.
PRI-EOP
(Procedural Interrupt-EOP)X1111100If there is an operator call from the sender, it is output after RTC.
PIP
(Procedural Interrupt Positive)X0110101This is output when an operator call is received.
 b.  Redundancy Compression Proces s Coding Mode
This unit uses one-dim ensiona l MH format.
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							8.6. NCU SECTION
8.6.1. GENERAL
This section is the interface between the telepho ne line and external telepho ne. It is composed of an EXT. TEL line relay (RY202),
bell detection circuit, TAM interface circuit, line amplifie r and side tone circuits and a multiplexer.
8.6.2. EXT. TEL. LINE RELAY (RY202)
 1. Circuit Operation
Normally, this relay switches to the external telepho ne side (break) and switches to the open side (make) while OFF-HOOK.
{ IC610 (149) High Level →CN616 (18) High Level} →CN202 (11) High Level →Q210 ON →RY202 ON →(make)
{ IC610 (145) Low Level →CN616 (22) Low Level} →CN202 (7) Low Level →PC203 ON →Q211 ON →(make)
8.6.3. BELL DETECTION CIRCUIT
 1.  Circuit Operation
The signal waveform for each point is indicate d below. The signal (low level section) input to pin T1 of ASIC IC604 on the digital
board is read by ASIC and judged as a bell.
TEL LINE →PC204 (1, 2 - 4) →IC604 (T1)
8.6.4. LINE AMPLIFIER AND SIDE TONE CIRCUIT
 1.  Circuit Operation
The reception signal output from the line transformer T201 is input to pin (6) of IC207 via R269, C285 and then the signal is
amplifie d at pin (7) of IC207 and sent to the reception system at 1.7dB.
The transmission signal goes through C243, R276 and enters IC207-pin (2), where the signal is amplifie d to about 27.2dB .
Then, it is output from pin (1) of IC207 and transmitted to T201 via C312, R293 and R292. W ithout a side tone circuit, the
transmission signal will return to the reception amplifie r via R269, C285. W hen the side tone circuit is active, the signal output
from IC207 pin (1) passes through C312, R291, C306, R284, R280, C300, R267 and C288 and goes into the amplifie r IC207
pin (5). This circuit is used to cancel the transmission return signal.
The TX signal is output to the circuit analog the route from the IC207 1 pin →C312 →R293 →R292 →T201 →TEL LINE.
However, if balance is lost in the bridge, a voltage occurs between the IC207 6 pin and 5 pin and a side tone results, because
the balance cannot be maintained completely at all frequencies in the audio range some side tone always occur.
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							8.6.5. REMOTE FAX ACTIVATION CIRCUIT
 1. Function
Anothe r telepho ne connected to same line activates the unit to the FAX mode by using a DTMF signal.
 2.  Signal Path
Refer to CHECK SHEET (P.137).
8.6.6. TAM INTERFACE CIRCUIT
This circuit is to switch between FAX receiving and the external TAM ’s message recording automatically. This circuit consists of a
transformer, multiplexer, amplifie r.
For details, please refer TAM INTERFACE SECTION (P.230).
8.7. ITS (Integrated telephone System) and MONITOR SECTION
8.7.1. GENERAL
The general ITS operation is performed by the special IC201 which has a handse t circuit. The alarm tone, the key tone, and
the beep are output from the ASIC IC604 (digital board).
8.7.1.1. TELEPHONE MONITOR
 1. Function
This is the function when you are not holding the handse t and can hear the caller ’s voice from the line.
 2.  Circuit Operation
(Teleph one Monitor Signal Path)
Signals received from the telepho ne line are output through at the speaker via the followin g path.
 3.  Signal Path
Refer to CHECK SHEET .
8.7.1.2. HANDSE T CIRCUIT
 1. Function
This circuit controls the conversation over the handse t, i.e. the transmitted and received voices to and from the handse t.
 2.  Signal Path (Transmission signal)
Refer to CHECK SHEET .
 3.  Signal path (Reception signal)
Refer to CHECK SHEET .
8.7.1.3. MONITOR CIRCUIT
 1. Function
This circuit monitors various tones, such as (1) DTMF tone, (2) Alarm/Beep/Ke y tone/Be ll.
 2.  Signal Path
 a. DTMF MONITOR
(Speaker Operation)
Refer to CHECK SHEET .
(Handset Operation)
Refer to CHECK SHEET .
 b.  ALARM/BEEP/ KEY TONE/BELL
Refer to CHECK SHEET .
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							8.7.1.4. LOW PASS FILTER
 1. Function
This low pass filter attenuates the 16-kHz account signal from the commutator to eliminate influenc e on the conversation and
communication .
 2.  Circuit Operation
This low pass filter is an eight-order active filter, and the cutoff frequency is approximately 4 kHz.
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							8.7.1.5. TAM INTERFACE SECTION
 1. Function
If EXT. TAM is selected in the Receive mode, the unit receives documents for FAX calls or the external TAM records a voice
message automatically.
To switch between the answering machine and facsimile in the EXT. TAM Mode.
#EXTERNAL TAM OPERATIONUNIT OPERATION
1W hen the bell signal rings as many times as the number
memorized into the connected answering machine (TAM),
the answering machine is connected to the line and the
answering message is sent out to the line. (OGM out for 8
~16sec.)The length of the answering message should be 8~16
seconds.
W hile the message is being played, the unit starts to
detect the CNG signal.(A)
If the unit detects the CNG signal, it will switch to FAX
receiving and disconnect the external TAM automatically.
2After sending the OGM, the answering machine starts to
record the message of the other party (ICM recording).If the unit detect the CNG signal or the unit will disconnect
the line. (C)
 2. Circuit Operation
The TAM INTERFACE circuit consists of CNG signal from the other party ’s detection circuit and RY202 (to separate EXT.
TAM).
 a.  CNG signal detection circuit
The CNG signal from the other party ’s FAX is detected in ASIC IC604 via CODEC(IC609) (digital board).
(Signal path)
Refer to CHECK SHEET (P.137).
 b.  Remote receiving
This is the parallel-conne cted DTMF signal for the TEL or EXT.TE L mode between T and R. W hen the other party is a FAX,
the unit switches to FAX receiving.
(Signal Path)
Detects the DTMF signal in the MODEM.
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