Toshiba GD-1221, GD-1220 service manual 3 V.8/V.34 communication sequence

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3.2.3V.8/V.34 communication sequence

1)Outline

-V.8 is performed as a startup procedure to switch to V.34. V.8 can connect an existing facsimile machine to the equipment using a data modem or other V-series modems. The V.34 modem has a modem circuit previously recommended, allowing it to be also connected to the existing modems while they are upper compatible.

-New technologies such as the pre-emphasis technology *1 and the probing technology *2 are fully used. The pre-emphasis technology *1 not only speeds up the modulation, but also gains the S/N ratio. The probing technology examines the line characteristics and optimizes the modem for the line condition. Therefore, not only do these technologies speed up the transmis- sion momentarily, but also the average speed of the process during the data transmission is increased.

-For V.8 and the pre/post-FAX transmission for V.34, the procedure is speeded up by the full duplex communication.

-Following 14 types of the image transmission speed are available: *3

33.6kbps/31.2 kbps/28.8 kbps/26.4 kbps/24.0 kbps/21.6 kbps/19.2 kbps/16.8 kbps/14.4 kbps/

12.0kbps/9.6 kbps/7.2 kbps/4.8 kbps/2.4 kbps

-The modulating speed (baud rate) *4 can be selected from 2,400, 3,000, 3,200 symbol/sec (man- datory), or 2,743, 2,800, 3,429 symbol/sec (option). The data rate can be set more accurately than the conventional modem.

*1 A signal is sent while raising the output level in the high-frequency band in which the noise is relatively loud.

*2 Tone signal called “Probing Tone” is sent for the receiver to examine the line characteris- tics of the line.

*3 In the ITU-T Recommendation, it is described as “data rate”. “Image transmission speed” is the same as “data rate”.

*4 In the ITU-T Recommendation, it is described as “symbol speed”. The “Symbol rate”, “Modulating speed”, and “Baud rate” are the same thing. This machine cannot realize the speed of 2,743 symbol/sec.

Notes:

1.ECM is used in the V.34 procedure. If the setting for the ECM transmission/reception of the user data is set to “Not performed”, the V.8 procedure is not performed and the procedure is not switched to V.34. V.17 or lower is selected in this case.

2.When the transmission/reception speed is set to 14.4 kbps or slower, the V.8 procedure is not performed, and V.17 or lower is selected.

3.See “Late start (P3-20)” to move to the V. 8/V.34 procedure after starting with the V.21 proce- dure.

4.After the V.34 procedure is started, the fallback for the V.34 procedure is performed. However, the fallback for the V.17 mode or lower mode is not performed.

GD-1220/1221

© 2006 - 2008 TOSHIBA TEC CORPORATION All rights reserved

DIALING/COMMUNICATION CONTROL

 

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Contents GD-1220/1221 Page Transportation/Installation Important Service Parts for Safety VorsichtContents 2006 2008 Toshiba TEC Corporation All rights reserved STUDIO165/205 Available STUDIO167/207/237 FAX OptionsGD-1220 GD-1221 Remarks System firmware versionSpecifications Embedded DBm to -8 dBm The setting can be changed by 1 dBTransmission system DBm to 0 dBm Level -55 dBm or lower cannot be detectedFolio Dimension width x length Printing areaComp Features Specifications and Outline of System 08/08 Following accessories and parts come with the FAX unit Accessories and PartsAccessory Qty Options Extends the FAX functions when the FAX unit is installedOption Function Model NA/EU/AU/TW System ListADF Radf Units and Components FAX Symbol Name FunctionLayout of PC Boards PWA-F-NCU-631LSU-RELATED Functions Recording paper sizeEffective recording area Size Horizontal x Vertical Effective recording areaSize Horizontal x Vertical Effective recording range For MJD, AUD, ASD, SAD, TWD, and CND models Unit mm inchInch Feed direction Mm 0.16 inch Effective recording area 297 x 293 x A4-R 210 x 206 x A5-R 148 x 144 x 257 x 253 xPrint mode Recording paper selection algorithm Recording paper selection algorithm and print algorithmPrint algorithm Reception print flowchart Start Receive FAX Judgment parameterDiscard printing Bit Discard parameterVertical reduction print Similar reduction print RTI ST-R Comp For MJD, AUD, ASD, SAD, TWD, CND modelsScanning Scanning widthRecording paper range For MJD, AUD, ASD, SAD, TWD, and CND modelsRecording paper range A4-R Recording paper range A4 long B4 long A3 long Recording paper range LT long Comp long LD longComp *2 Comp *1 Folio Folio *1Error processing Limitations on reception print Order DrawerLSU-RELATED Functions YES Circuit Connection and Procedure to Change ModeDial call-up transmission to a telephone circuit Standby stateCommunication mode Toshiba original procedure Selection of the communication modeProcedure to select the transmission mode Telephone circuitThis signal can be sent manually Signal form Signaling System Diagram and Signal FormsCircuit control signals Signal name Signal formMode change is possible only for the original set manually Communication with the binary signalsImage signal ReceiverOnly error frame retransmitted 1 completed 2 completed Frames received Error occurredCFR CED NsfcsidisMCF Binary signals PRI-EOM PIPPIN PRI-MPSFCF FIF FCS When this frame is the last frame, X =Format FCF format of each binary signal Binary signal Format4800 bps, 2400 bps 9600 bps, 7200 bpsTCF 3 V.8/V.34 communication sequence Standard procedure Transmitter Receiver Line closedSignal name Abbreviation Function Remarks 150 Hz Tone signal betweenHz and 3,750 Hz in units Frequency transmission CapabilityTRN ALTTransmitter Maintains the synchroniza 7E H TionReceives an NSF sent from ReceiverIs completed Image data Image data are sent. TransmitterScrambled data frame to be Encoded image data Turn off Scrambled 1 is sent forTransmission of one Is completed Short training SignalPPS-EOP Informs to disconnect the lineLine closed DIS cannot be recognized DIALING/COMMUNICATION Control DIALING/COMMUNICATION Control DIALING/COMMUNICATION Control DIALING/COMMUNICATION Control FAX mode FAX Automatic SwitchingTEL mode General functionsDIALING/COMMUNICATION Control Configuration GD-1220/1221Configuration Description of CircuitsEU/AU/AS/C models CML1 Line path switching control circuitSignal Name Type Active Description Destination ATT3DB1IC3 RLY3, IC3IC5 Line 1 Dial Pulse Generation Signal Q53 Dial pulse generation circuitLine 1 Dial Pulse Generation Signal Line current detection circuit Line Current Detection Signal IC23Line Reverse Current Detection Signal IC23 REVA1Line 1 Current Detection Signal IC23 Current Reverse Line 1 Current Detection IC23 SignalLine 1 CI Detect Signal IC23 CI detection circuitLine 1 CI Detection Signal IC23 Line monitor circuit FAX boardLine Monitor Monitoring signalRinger/Alarm LOW HighSound volume PC Boards PWA-F-FAX-635 GD-1220PWA-F-FAX-678 GD-1221 PWA-F-NCU-631 NAD, TWD, SAD PWA-F-NCU-631 MJD, AUD, ASD, CND Electrical Circuits Installation Explanation to the UsersInstallation
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