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KX-FT937LA-B
6.6.2.
Modem Circuit Operation
The modem (IC5) has all the hardware satisfying the CCITT standards mentioned previously.
When the ASIC IC1 (61) is brought to a low level, the modem (IC5) is chip-selected and the resistors inside IC are selected by the
select signals from ASIC (IC1) ADR0-ADR4. The commands are written through the data bus, and all the processing is controlled
by the ASIC (IC1) according to CCITT procedures. The INT signal dispatched from IRQ (pins 100 of IC5) to ASIC (IC1) when the
transmission data is accepted and the received data is demodulated, the ASIC (IC1) implements post processing. This modem
(IC5) has an automatic application equalizer.
With training signal 1 or 2 during G3 reception, it can automatically establish the optimum equalizer. The modem (IC5) operates
using the 32.256 MHz clock (X3).
1.
Facsimile Transmission
The digital image data on the data bus is modulated in the modem (IC5), and sent from pin 69 via Analog SW IC10, amplifier
IC9 and the NCU section to the telephone line.
Refer to
Signal Route
(P.108).
2.
Facsimile Reception
The analog image data which is received from the telephone line passes through the NCU section and enters pin 47 of the
modem (IC5). The signals that enter pin 47 of the modem (IC5) are demodulated in the board to digital image signals, then
placed on the data bus.
In this case, the image signals from the telephone line are transmitted serially. Hence, they are placed on the bus in 8 bit
units. Here, the internal equalizer circuit reduces the image signals to a long-distance receiving level.
This is designed to correct the characteristics of the frequency band centered about 3 kHz and maintain a constant receiving
sensitivity. It can be set in the service mode.
Refer to
Signal Route
(P.108).
3.
DTMF Transmission (Monitor tone)
The DTMF signal generated in the modem (IC5) is output from pin 56, and is then sent to the circuit on the same route as
used for facsimile transmission.
Refer to
Signal Route
(P.108).
(DTMF Monitor Tone)
Refer to
Signal Route
(P.108).
4.
Call Tone Transmission
This is the call signal which is generated in the ASIC (IC1) and sent to the speaker.
Refer to
Signal Route
(P.108).
5.
Busy/Dial Tone Detection
The path is the same as FAX receiving. When it is detected, the carrier detect bit of the resistor in the modem (IC5) becomes
1, and this status is monitored by the ASIC (IC1).
6.
Caller ID Detection
The caller ID signal which is received from the telephone line/passes through IC1 pin (2-1). And it enters pin 50 of the modem
(IC5).
Содержание KX-FT937LA-B
Страница 11: ...11 KX FT937LA B 6 Technical Descriptions 6 1 Connection Diagram ...
Страница 21: ...21 KX FT937LA B 6 4 2 Block Diagram ...
Страница 23: ...23 KX FT937LA B ...
Страница 35: ...35 KX FT937LA B b Redundancy Compression Process Coding Mode This unit uses one dimensional MH format ...
Страница 66: ...66 KX FT937LA B The unit is too hot Stop using the unit for a while and let the unit cool down ...
Страница 68: ...68 KX FT937LA B ...
Страница 69: ...69 KX FT937LA B CROSS REFERENCE Test Mode P 54 ...
Страница 70: ...70 KX FT937LA B CROSS REFERENCE Test Mode P 54 ...
Страница 71: ...71 KX FT937LA B CROSS REFERENCE Test Mode P 54 ...
Страница 72: ...72 KX FT937LA B CROSS REFERENCE Test Mode P 54 ...
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Страница 75: ...75 KX FT937LA B CROSS REFERENCE Test Mode P 54 ...
Страница 102: ...102 KX FT937LA B NG Wave pattern Note Refer to NG Example P 107 ...
Страница 104: ...104 KX FT937LA B I O and Pin No Diagram ...
Страница 106: ...106 KX FT937LA B ...
Страница 107: ...107 KX FT937LA B 12 5 5 3 NG Example ...
Страница 111: ...111 KX FT937LA B 12 5 7 2 Troubleshooting Flow Chart ...
Страница 115: ...115 KX FT937LA B 12 5 10 CIS Contact Image Sensor Section Refer to Scanning Block P 24 CROSS REFERENCE Test Mode P 54 ...
Страница 116: ...116 KX FT937LA B 12 5 11 Thermal Head Section Refer to Thermal Head P 22 ...
Страница 117: ...117 KX FT937LA B 13 Service Fixture Tools ...
Страница 120: ...120 KX FT937LA B 14 2 Disassembly Procedure 14 2 1 How to Remove the Paper Stacker ...
Страница 121: ...121 KX FT937LA B 14 2 2 How to Remove the Operation Panel Block ...
Страница 122: ...122 KX FT937LA B 14 2 3 How to Remove the Operation Board LCD and Platen Roller ...
Страница 123: ...123 KX FT937LA B 14 2 4 How to Remove the Separation Holder and Document Feed Support ...
Страница 124: ...124 KX FT937LA B 14 2 5 How to Remove the Image Sensor CIS and Feed Roller ...
Страница 125: ...125 KX FT937LA B 14 2 6 How to Remove the Cutter Unit ...
Страница 126: ...126 KX FT937LA B 14 2 7 How to Remove the Lock Lever and Thermal Head ...
Страница 127: ...127 KX FT937LA B 14 2 8 How to Remove the Bottom Frame ...
Страница 128: ...128 KX FT937LA B 14 2 9 How to Remove the Analog Board Digital Board Power Supply Board and Power Cord ...
Страница 130: ...130 KX FT937LA B 14 2 12 Installation Position of the Lead Wires ...
Страница 138: ...138 KX FT937LA B 15 2 3 4 Copying CROSS REFERENCE Sensor Section P 114 ...
Страница 142: ...142 KX FT937LA B 16 1 4 Power Supply Board ...
Страница 146: ...146 KX FT937LA B Refer to Analog Board Section P 108 ...
Страница 147: ...147 KX FT937LA B 16 3 Test Chart 16 3 1 ITU T No 1 Test Chart ...
Страница 148: ...148 KX FT937LA B 16 3 2 ITU T No 2 Test Chart ...
Страница 155: ...155 KX FT937LA B MEMO ...
Страница 165: ...165 KX FT937LA B 20 1 2 Upper Cabinet Section ...
Страница 166: ...166 KX FT937LA B 20 1 3 Lower Cabinet Section ...
Страница 167: ...167 KX FT937LA B 20 1 4 Gear Block Section ...
Страница 168: ...168 KX FT937LA B 20 1 5 Screws ...
Страница 169: ...169 KX FT937LA B 20 1 6 Accessories and Packing Materials ...