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       # BEST DATA PRODUCTS, INC.
       
          1442F INTERNAL FAX/DATA MODEM
       
          Card Type              Fax, Modem (synchronous/asynchronous)   
          Chip Set               Unidentified                            
          Maximum Data Rate      14.4Kbps                                
          Maximum Fax Rate       14.4Kbps                                
          Data Bus               8-bit ISA                               
          Fax Class              Class I & II                            
          Data Modulation        Bell 103/212A                           
          Protocol                                                       
                                 ITU-T V.21, V.22, V.22bis, V.23, V.32,  
                                 V.32bis                                 
          Fax Modulation         ITU-T V.17, V.21CH2, V.27ter, V.29      
          Protocol               
          Error                  MNP5, V.42, V.42bis                     
          Correction/Compression 
       
                                                                   V2327
       
          +-------------------------------+
          | MISCELLANEOUS TECHNICAL NOTES |
          |-------------------------------|
          |      Diagram not available    |
          +-------------------------------+
       
          +------------------------------------------------------------+
          |                    SERIAL PORT ADDRESS                     |
          |------------------------------------------------------------|
          |      Setting       |       SW1/5       |       SW1/6       |
          |--------------------+-------------------+-------------------|
          |    COM1 (3F8h)     |        On         |        On         |
          |--------------------+-------------------+-------------------|
          |   í COM2 (2F8h)    |        On         |        Off        |
          |--------------------+-------------------+-------------------|
          |    COM3 (3E8h)     |        Off        |        On         |
          |--------------------+-------------------+-------------------|
          |    COM4 (2E8h)     |        Off        |        Off        |
          +------------------------------------------------------------+
       
          +------------------------------------------------------------+
          |                    INTERRUPT SELECTION                     |
          |------------------------------------------------------------|
          |  Setting   |   SW1/1   |   SW1/2   |   SW1/3   |   SW1/4   |
          |------------+-----------+-----------+-----------+-----------|
          |    í 3     |    On     |    Off    |    Off    |    Off    |
          |------------+-----------+-----------+-----------+-----------|
          |     4      |    Off    |    On     |    Off    |    Off    |
          |------------+-----------+-----------+-----------+-----------|
          |     5      |    Off    |    Off    |    On     |    Off    |
          |------------+-----------+-----------+-----------+-----------|
          |     7      |    Off    |    Off    |    Off    |    On     |
          +------------------------------------------------------------+
       
          +------------------------------------------------------------+
          |                   SUPPORTED COMMAND SET                    |
          |------------------------------------------------------------|
          |                     Basic AT Commands                      |
          |------------------------------------------------------------|
          | AT, ‘+++’, ‘Comma’, A/                                     |
          |------------------------------------------------------------|
          | A, B, C, D, E, F, , H, L, M, N, O, P, Q, S, T, V, W, X, Y, |
          | Z                                                          |
          |------------------------------------------------------------|
          | &C, &D, &F, &G, &J, &K, &L, &M, &P, &Q, &R, &S, &T, &V,    |
          | &W, &X, &Y, &Z                                             |
          |------------------------------------------------------------|
          |                    Extended AT Commands                    |
          |------------------------------------------------------------|
          | \A, \B, \G, \L, \O, \T, \U, \Y, \Z, %E, %L, %Q             |
          |------------------------------------------------------------|
          |                        S Registers                         |
          |------------------------------------------------------------|
          | S0, S1, S2, S3, S4, S5, S6, S7, S8, S9, S10, S11, S12,     |
          | S16, S18, S22, S25, S26, S36, S38, S46                     |
          |------------------------------------------------------------|
          | S48, S82, S86, S91, S95                                    |
          |------------------------------------------------------------|
          | Note: See MHI Help file for full command documentation.    |
          +------------------------------------------------------------+
       
                            Proprietary AT Command Set
       
          +------------------------------------------------------------+
          |                  BIT-MAPPED REGISTER S14                   |
          |------------------------------------------------------------|
          | Format:      | AT [cmds] S14=n [cmds]                      |
          |--------------+---------------------------------------------|
          | Default:     | 170                                         |
          |--------------+---------------------------------------------|
          | Range:       | 0-255                                       |
          |--------------+---------------------------------------------|
          | Unit:        | Bit-mapped                                  |
          |--------------+---------------------------------------------|
          | Description: | Controls local echo, command echo, result   |
          |              | codes and display, dial mode, and           |
          |              | answer/originate mode.                      |
          |--------------+---------------------------------------------|
          | Bit  | Value |                  Function                   |
          |------+-------+---------------------------------------------|
          |  0   |   í 0 | Disable local echo                          |
          |      |       |                                             |
          |      |     1 | Enable local echo                           |
          |------+-------+---------------------------------------------|
          |  1   |     0 | Command echo disabled                       |
          |      |       |                                             |
          |      |   í 1 | Command echo enabled                        |
          |------+-------+---------------------------------------------|
          |  2   |   í 0 | Result codes enabled                        |
          |      |       |                                             |
          |      |     1 | Result codes disabled                       |
          |------+-------+---------------------------------------------|
          |  3   |     0 | Display result codes in numeric format      |
          |      |       |                                             |
          |      |   í 1 | Display result codes in verbose format      |
          |------+-------+---------------------------------------------|
          |  4   |   í 0 | Smart mode enabled                          |
          |      |       |                                             |
          |      |     1 | Dumb mode enabled                           |
          |------+-------+---------------------------------------------|
          |  5   |     0 | Tone dial enabled                           |
          |      |       |                                             |
          |      |   í 1 | Pulse dial enabled                          |
          |------+-------+---------------------------------------------|
          |  6   |   í 0 | Result codes enabled                        |
          |      |       |                                             |
          |      |     1 | Result codes enabled when originating       |
          |------+-------+---------------------------------------------|
          |  7   |     0 | Answer mode enabled                         |
          |      |       |                                             |
          |      |   í 1 | Originate mode enabled                      |
          +------------------------------------------------------------+
       
          +------------------------------------------------------------+
          |                  BIT-MAPPED REGISTER S21                   |
          |------------------------------------------------------------|
          | Format       | AT [cmds] S21=n [cmds]                      |
          |--------------+---------------------------------------------|
          | Default:     | 0                                           |
          |--------------+---------------------------------------------|
          | Range:       | 0-255                                       |
          |--------------+---------------------------------------------|
          | Unit:        | Bit-mapped                                  |
          |--------------+---------------------------------------------|
          | Description: | Selects jack type, setting profile,         |
          |              | CTS/DCD/DSR signals, low DTR action, and    |
          |              | the long space disconnect function.         |
          |--------------+---------------------------------------------|
          | Bit  | Value |                  Function                   |
          |------+-------+---------------------------------------------|
          |  0   |   í 0 | Selects RJ-11, RJ-41S, or RJ45S jack        |
          |      |       |                                             |
          |      |     1 | Selects RJ-12 or RJ-13 jack                 |
          |------+-------+---------------------------------------------|
          |  1   |   í 0 | Default profile                             |
          |      |       |                                             |
          |      |     1 | User-defined profile                        |
          |------+-------+---------------------------------------------|
          |  2   |   í 0 | CTS follows RTS                             |
          |      |       |                                             |
          |      |     1 | CTS forced high                             |
          |------+-------+---------------------------------------------|
          | 4, 3 |  í 00 | DTR signal ignored                          |
          |      |       |                                             |
          |      |    01 | Modem goes to command mode on low DTR       |
          |      |       |                                             |
          |      |    10 | Modem disconnects on low DTR; Auto-Answer   |
          |      |       | is disabled.                                |
          |      |    11 |                                             |
          |      |       | Modem is initialized on low DTR             |
          |------+-------+---------------------------------------------|
          |  5   |   í 0 | DCD forced high                             |
          |      |       |                                             |
          |      |     1 | DCD normal                                  |
          |------+-------+---------------------------------------------|
          |  6   |   í 0 | DSR forced high                             |
          |      |       |                                             |
          |      |     1 | DSR normal                                  |
          |------+-------+---------------------------------------------|
          |  7   |   í 0 | Long space disconnect function disabled     |
          |      |       |                                             |
          |      |     1 | Long space disconnect function enabled      |
          +------------------------------------------------------------+
       
          +------------------------------------------------------------+
          |                  BIT-MAPPED REGISTER S23                   |
          |------------------------------------------------------------|
          | Format       | AT [cmds] S23=n [cmds]                      |
          |--------------+---------------------------------------------|
          | Default:     | 7                                           |
          |--------------+---------------------------------------------|
          | Range:       | 0-191                                       |
          |--------------+---------------------------------------------|
          | Unit:        | Bit-mapped                                  |
          |--------------+---------------------------------------------|
          | Description: | Grants/denies remote digital loopback,      |
          |              | controls DTE rate and parity, and sets      |
          |              | guard tone.                                 |
          |--------------+---------------------------------------------|
          | Bit  | Value |                  Function                   |
          |------+-------+---------------------------------------------|
          |  0   |     0 | Remote digital loopback denied              |
          |      |       |                                             |
          |      |   í 1 | Remote digital loopback allowed             |
          |------+-------+---------------------------------------------|
          | 3 -  |   000 | Sets serial port speed to 0-300bps          |
          |  1   |       |                                             |
          |      |   001 | Sets serial port speed to 600bps            |
          |      |       |                                             |
          |      |   010 | Sets serial port speed to 1200bps           |
          |      |       |                                             |
          |      | í 011 | Sets serial port speed to 2400bps           |
          |      |       |                                             |
          |      |   100 | Sets serial port speed to 4800bps           |
          |      |       |                                             |
          |      |   101 | Sets serial port speed to 9600bps           |
          |      |       |                                             |
          |      |   110 | Sets serial port speed to 19200bps          |
          |      |       |                                             |
          |      |   111 | Sets serial port speed to 38400bps          |
          |------+-------+---------------------------------------------|
          | 5, 4 |  í 00 | Parity even                                 |
          |      |       |                                             |
          |      |    01 | Space Parity                                |
          |      |       |                                             |
          |      |    10 | Parity odd                                  |
          |      |       |                                             |
          |      |    11 | Mark or No Parity                           |
          |------+-------+---------------------------------------------|
          | 7, 6 |  í 00 | Guard tone disabled                         |
          |      |       |                                             |
          |      |    01 | Guard tone 550Hz enabled                    |
          |      |       |                                             |
          |      |    10 | Guard tone 1800Hz enabled                   |
          +------------------------------------------------------------+
       
          +------------------------------------------------------------+
          |                  BIT-MAPPED REGISTER S27                   |
          |------------------------------------------------------------|
          | Format       | AT [cmds] S27=n [cmds]                      |
          |--------------+---------------------------------------------|
          | Default:     | 64                                          |
          |--------------+---------------------------------------------|
          | Range:       | 0-127                                       |
          |--------------+---------------------------------------------|
          | Unit:        | Bit-mapped                                  |
          |--------------+---------------------------------------------|
          | Description: | Selects synchronous/asynchronous mode, line |
          |              | type, clock source, and ITU-T/Bell modes.   |
          |--------------+---------------------------------------------|
          | Bit  | Value |                  Function                   |
          |------+-------+---------------------------------------------|
          |  3,  | í 000 | Asynchronous mode, serial port speed        |
          | 1, 0 |       | follows connect speed                       |
          |      |   001 |                                             |
          |      |       | Asynchronous off-line command mode and      |
          |      |   010 | synchronous connect mode                    |
          |      |       |                                             |
          |      |   011 | Asynchronous off-line command mode; modem   |
          |      |       | autodials first number in directory, then   |
          |      |   100 | synchronous connect mode                    |
          |      |       |                                             |
          |      |   101 | Asynchronous off-line command mode on low   |
          |      |       | DTR, synchronous connect mode on high DTR   |
          |      |   110 |                                             |
          |      |       | Modem returns ‘OK’                          |
          |      |   111 |                                             |
          |      |       | Error correction mode                       |
          |      |       |                                             |
          |      |       | Asynchronous mode during Normal connect     |
          |      |       | mode                                        |
          |      |       |                                             |
          |      |       | Modem returns ‘OK’                          |
          |------+-------+---------------------------------------------|
          |  2   |   í 0 | Switched line                               |
          |      |       |                                             |
          |      |     1 | Leased line                                 |
          |------+-------+---------------------------------------------|
          | 5, 4 |  í 00 | Local modem generates transmit clock source |
          |      |       |                                             |
          |      |    01 | Local DTE generates transmit clock source   |
          |      |       |                                             |
          |      |    10 | Remote DCE/DTE generates transmit clock     |
          |      |       | source                                      |
          |------+-------+---------------------------------------------|
          |  6   |     0 | ITU/T mode                                  |
          |      |       |                                             |
          |      |   í 1 | Bell mode                                   |
          +------------------------------------------------------------+
       
          +------------------------------------------------------------+
          |                  BIT-MAPPED REGISTER S40                   |
          |------------------------------------------------------------|
          | Format       | AT [cmds] S40=n [cmds]                      |
          |--------------+---------------------------------------------|
          | Default:     | 119                                         |
          |--------------+---------------------------------------------|
          | Range:       | 0-255                                       |
          |--------------+---------------------------------------------|
          | Unit:        | Bit-mapped                                  |
          |--------------+---------------------------------------------|
          | Description: | Controls connect mode, break handling, MNP  |
          |              | block size, and flow control.               |
          |--------------+---------------------------------------------|
          | Bit  | Value |                  Function                   |
          |------+-------+---------------------------------------------|
          | 1, 0 |    00 | Normal mode enabled                         |
          |      |       |                                             |
          |      |    01 | Direct mode enabled                         |
          |      |       |                                             |
          |      |    10 | Reliable mode enabled                       |
          |      |       |                                             |
          |      |  í 11 | Auto-reliable mode enabled                  |
          |------+-------+---------------------------------------------|
          |  4,  |   000 | \K0                                         |
          | 3, 2 |       |                                             |
          |      |   001 | \K1                                         |
          |      |       |                                             |
          |      |   010 | \K2                                         |
          |      |       |                                             |
          |      |   011 | \K3                                         |
          |      |       |                                             |
          |      |   100 | \K4                                         |
          |      |       |                                             |
          |      | í 101 | \K5                                         |
          |------+-------+---------------------------------------------|
          | 6, 5 |    00 | MNP block size is 64 characters             |
          |      |       |                                             |
          |      |    01 | MNP block size is 128 characters            |
          |      |       |                                             |
          |      |    10 | MNP block size is 192 characters            |
          |      |       |                                             |
          |      |  í 11 | MNP block size is 256 characters            |
          |------+-------+---------------------------------------------|
          |  7   |   í 0 | Flow control disabled                       |
          |      |       |                                             |
          |      |     1 | Flow control enabled                        |
          +------------------------------------------------------------+
       
          +------------------------------------------------------------+
          |                  BIT-MAPPED REGISTER S41                   |
          |------------------------------------------------------------|
          | Format       | AT [cmds] S41=n [cmds]                      |
          |--------------+---------------------------------------------|
          | Default:     | 1                                           |
          |--------------+---------------------------------------------|
          | Range:       | 0-7                                         |
          |--------------+---------------------------------------------|
          | Unit:        | Bit-mapped                                  |
          |--------------+---------------------------------------------|
          | Description: | Selects compression, auto-retrain, and MNP  |
          |              | mode.                                       |
          |--------------+---------------------------------------------|
          | Bit  | Value |                  Function                   |
          |------+-------+---------------------------------------------|
          |  0   |     0 | Data compression disabled                   |
          |      |       |                                             |
          |      |   í 1 | Data compression enabled                    |
          |------+-------+---------------------------------------------|
          |  1   |   í 0 | Auto-retrain disabled                       |
          |      |       |                                             |
          |      |     1 | Auto-retrain enabled                        |
          |------+-------+---------------------------------------------|
          |  2   |   í 0 | Stream mode for MNP                         |
          |      |       |                                             |
          |      |     1 | Block mode for MNP                          |
          +------------------------------------------------------------+
       
          +------------------------------------------------------------+
          |                         BREAK TYPE                         |
          |------------------------------------------------------------|
          | Type:               | Configuration                        |
          |---------------------+--------------------------------------|
          | Format:             | AT [cmds] \Kn [cmds]                 |
          |---------------------+--------------------------------------|
          | Description:        | Configures action of break signal    |
          |------------------------------------------------------------|
          |  Command  |  Break from  | Break received | Break from DTE |
          |           |  DTE during  |  from remote   | during Direct  |
          |           |   MNP mode   |     modem      |      mode      |
          |-----------+--------------+----------------+----------------|
          |    \K0    | Online       | Buffers        | Online command |
          |           | command mode | cleared, break | mode enabled,  |
          |           | enabled,     | sent to DTE    | send no break  |
          |           | send no      |                | to remote      |
          |           | break to     |                | modem          |
          |           | remote modem |                |                |
          |-----------+--------------+----------------+----------------|
          |    \K1    | Break sent   | Buffers        | Break sent to  |
          |           | to remote    | cleared, break | remote modem   |
          |           | modem and    | sent to DTE    | and buffers    |
          |           | buffers      |                | cleared        |
          |           | cleared      |                |                |
          |-----------+--------------+----------------+----------------|
          |    \K2    | Online       | Break sent     | Online command |
          |           | command mode | immediately to | mode enabled,  |
          |           | enabled,     | DTE            | send no break  |
          |           | send no      |                | to remote      |
          |           | break to     |                | modem          |
          |           | remote modem |                |                |
          |-----------+--------------+----------------+----------------|
          |    \K3    | Send break   | Break sent     | Send break to  |
          |           | to remote    | immediately to | remote modem   |
          |           | modem        | DTE            | immediately    |
          |           | immediately  |                |                |
          |-----------+--------------+----------------+----------------|
          |    \K4    | Online       | Break sent     | Online command |
          |           | command mode | with received  | mode enabled,  |
          |           | enabled,     | data to the    | send no break  |
          |           | send no      | DTE            | to remote      |
          |           | break to     |                | modem          |
          |           | remote modem |                |                |
          |-----------+--------------+----------------+----------------|
          |    \K5    | Send break   | Break sent     | Send break     |
          |           | with         | with received  | with           |
          |           | transmitted  | data to the    | transmitted    |
          |           | data         | DTE            | data           |
          +------------------------------------------------------------+
       
          +------------------------------------------------------------+
          |                        COMPRESSION                         |
          |------------------------------------------------------------|
          | Type:        | Configuration                               |
          |--------------+---------------------------------------------|
          | Format:      | AT [cmds] %Cn [cmds]                        |
          |--------------+---------------------------------------------|
          | Description: | Selects data compression                    |
          |--------------+---------------------------------------------|
          |   Command    |                  Function                   |
          |--------------+---------------------------------------------|
          |     %C0      | Data compression disabled                   |
          |--------------+---------------------------------------------|
          |    í %C1     | Data compression enabled                    |
          +------------------------------------------------------------+
       
          +------------------------------------------------------------+
          |                        CONNECT MODE                        |
          |------------------------------------------------------------|
          | Type:        | Configuration                               |
          |--------------+---------------------------------------------|
          | Format:      | AT [cmds] \Nn [cmds]                        |
          |--------------+---------------------------------------------|
          | Description: | Controls the type of connection the modem   |
          |              | will operate in                             |
          |--------------+---------------------------------------------|
          |   Command    |                  Function                   |
          |--------------+---------------------------------------------|
          |     \N0      | Normal mode enabled                         |
          |--------------+---------------------------------------------|
          |     \N1      | Direct mode enabled                         |
          |--------------+---------------------------------------------|
          |     \N2      | Reliable mode enabled                       |
          |--------------+---------------------------------------------|
          |    í \N3     | Auto-reliable mode enabled                  |
          +------------------------------------------------------------+
       
          +------------------------------------------------------------+
          |                       DCE LINE SPEED                       |
          |------------------------------------------------------------|
          | Type:        | Register                                    |
          |--------------+---------------------------------------------|
          | Format       | AT [cmds] S37=n [cmds]                      |
          |--------------+---------------------------------------------|
          | Description: | Sets the maximum allowable data exchange    |
          |              | rate attempted during handshake process.    |
          |--------------+---------------------------------------------|
          |   Command    |                  Function                   |
          |--------------+---------------------------------------------|
          |   í S37=0    | Speed of last connection                    |
          |--------------+---------------------------------------------|
          |    S37=1     | 300bps                                      |
          |--------------+---------------------------------------------|
          |    S37=2     | 300bps                                      |
          |--------------+---------------------------------------------|
          |    S37=3     | 300bps                                      |
          |--------------+---------------------------------------------|
          |    S37=5     | 1200bps                                     |
          |--------------+---------------------------------------------|
          |    S37=6     | 2400bps                                     |
          |--------------+---------------------------------------------|
          |    S37=8     | 4800bps                                     |
          |--------------+---------------------------------------------|
          |    S37=9     | 9600bps                                     |
          |--------------+---------------------------------------------|
          |    S37=10    | 12.0Kbps                                    |
          |--------------+---------------------------------------------|
          |    S37=11    | 14.4Kbps                                    |
          |--------------+---------------------------------------------|
          |    S37=12    | 7200bps                                     |
          +------------------------------------------------------------+
       
          +------------------------------------------------------------+
          |                     ECHO CANCELLATION                      |
          |------------------------------------------------------------|
          | Type:        | Configuration                               |
          |--------------+---------------------------------------------|
          | Format:      | AT [cmds] \En [cmds]                        |
          |--------------+---------------------------------------------|
          | Description: | Optimize echo cancellation                  |
          +------------------------------------------------------------+
       
          +------------------------------------------------------------+
          |                     REPORT INFORMATION                     |
          |------------------------------------------------------------|
          | Type:        | Immediate                                   |
          |--------------+---------------------------------------------|
          | Format:      | AT [cmds] In [cmds]                         |
          |--------------+---------------------------------------------|
          | Description: | Displays information requested              |
          |--------------+---------------------------------------------|
          |   Command    |                  Function                   |
          |--------------+---------------------------------------------|
          |      I0      | Reports product code                        |
          |--------------+---------------------------------------------|
          |      I1      | Reports ROM checksum                        |
          |--------------+---------------------------------------------|
          |      I2      | Tests and reports ROM checksum, as ‘OK’ or  |
          |              | ‘ERROR’                                     |
          |--------------+---------------------------------------------|
          |      I3      | Reports firmware manufacturer               |
          |              | identification and checksum                 |
          |--------------+---------------------------------------------|
          |      I4      | Reports product capabilities                |
          +------------------------------------------------------------+
       
          +------------------------------------------------------------+
          |                  V.42 - CLEAR DICTIONARY                   |
          |------------------------------------------------------------|
          | Type:        | Immediate                                   |
          |--------------+---------------------------------------------|
          | Format:      | AT [cmds] %P [cmds]                         |
          |--------------+---------------------------------------------|
          | Description: | Clears the V.42 encoder dictionary          |
          +------------------------------------------------------------+
       
          +------------------------------------------------------------+
          |               V.42bis - COMPRESSION CONTROL                |
          |------------------------------------------------------------|
          | Type:        | Configuration                               |
          |--------------+---------------------------------------------|
          | Format:      | AT [cmds] %Mn [cmds]                        |
          |--------------+---------------------------------------------|
          | Description: | Controls V.42bis data compression           |
          |--------------+---------------------------------------------|
          |   Command    |                  Function                   |
          |--------------+---------------------------------------------|
          |     %M0      | V.42bis disabled                            |
          |--------------+---------------------------------------------|
          |     %M1      | V.42bis when transmitting enabled           |
          |--------------+---------------------------------------------|
          |     %M2      | V.42bis when receiving enabled              |
          |--------------+---------------------------------------------|
          |    í %M3     | V.42bis when transmitting/receiving enabled |
          +------------------------------------------------------------+
       
          +------------------------------------------------------------+
          |                 V.42bis - DICTIONARY SIZE                  |
          |------------------------------------------------------------|
          | Type:        | Configuration                               |
          |--------------+---------------------------------------------|
          | Format:      | AT [cmds] %Dn [cmds]                        |
          |--------------+---------------------------------------------|
          | Description: | Select V.42 dictionary size                 |
          |--------------+---------------------------------------------|
          |   Command    |                  Function                   |
          |--------------+---------------------------------------------|
          |     %D0      | Select 512 bytes                            |
          |--------------+---------------------------------------------|
          |     %D1      | Select 1024 bytes                           |
          |--------------+---------------------------------------------|
          |    í %D2     | Select 2048 bytes                           |
          |--------------+---------------------------------------------|
          |     %D3      | Select 4096 bytes, one-way compression      |
          +------------------------------------------------------------+
       
          +------------------------------------------------------------+
          |              V.42bis - MAXIMUM STRING LENGTH               |
          |------------------------------------------------------------|
          | Type:        | Immediate                                   |
          |--------------+---------------------------------------------|
          | Format:      | AT [cmds] %Sn [cmds]                        |
          |--------------+---------------------------------------------|
          | Default:     | 32                                          |
          |--------------+---------------------------------------------|
          | Range:       | 6-250                                       |
          |--------------+---------------------------------------------|
          | Unit:        | Characters                                  |
          |--------------+---------------------------------------------|
          | Description: | Selects string size for V.42bis compression |