wsc4vb_u.txt

在VB中实现通讯的例子

      "_declspec" keywords are specified.

      For more information on the C/C++ version of WSC, download the latest
      version of WSC4C from our web site at www.marshallsoft.com.

      3.2 Compiling Example Programs

      Visual Basic MAK files are provided with all example programs. All
      example source code is saved in Visual Basic 3.0 format so that it
      can be read by all versions of Visual Basic.

      3.3 EXCEL, ACCESS, and WORD

      WSC can be used with Microsoft VBA (Visual Basic for Applications)
      applications such as EXCEL, ACCESS, and WORD. Note that WSC16.DLL
      must be used for 16-bit applications, even if running under Windows
      95/98 or NT. See EXCEL.TXT, ACCESS.TXT, and WORD.TXT for more
      information.

      3.4 PowerBuilder and FoxPro

      WSC can also be used with Power Builder and FoxPro applications.

      WSC.PBI : Power Builder declaration file.
      WSC.PRG : FoxPro declaration file.

      See PBUILDER.TXT and FOXPRO.TXT for more information.











     WSC4VB Users Manual                                       Page 7

      4.0 MODEM I/O (MIO)

      4.1 MIO Introduction

      The file MIO32.BAS contains prototypes for using the Modem I/O DLL.
      These functions ease communicating with modems using AT commands.

      The MIO functions are broken down into parts called states, and
      control is returned to Windows between executing each state.

      For example:

      (1) Send the string to the MIO driver by executing:

      Code = mioSendTo(Port,100,"!ATDT1,256,880,9748")

      The '!' characters are converted to carriage returns.  The text
      string is copied into the driver's data area.

      (2) Call mioDriver (typically based on a timer) until MIO_IDLE is
      returned. Each time mioDriver is called, it will send another
      character to the modem provided the required delay (since the
      previous character was sent) has passed.  If the delay has not
      passed, the driver simply returns MIO_RUNNING, but without actually
      sending a character to the modem.  Once all characters have been
      sent, mioDriver will return MIO_IDLE, indicating it is done and is
      ready to accept another function.

      mioDriver will return MIO_RUNNING if it is still processing. Any
      other return value indicates that it is still processing and the
      returned value is a character from the modem that can be displayed if
      wanted.

      (3) Once mioDriver returns MIO_IDLE, call mioResult to get the
      result of the mioSendTo call.

      4.2 MIO Function Summary

       mioDriver : Drives the execution of mioSendTo, mioWaitFor, or
                   mioQuiet once they have been started.
        mioBreak : Forces the MIO driver to IDLE state.
       mioSendTo : Sends a string (including control chars) to the modem.
      mioWaitFor : Waits  for a particular string from the modem, passing
                   all else through.
        mioQuiet : Waits for continuous quiet of a specified duration.
        mioBreak : Breaks further modem I/O activity.

      Refer to the WSC4VB Reference Manual (WSC4VB_R.TXT) for more
      detailed information.









     WSC4VB Users Manual                                       Page 8

      5.0 XMODEM & YMODEM


      5.1 XYDRIVER Introduction

      The XMODEM & YMODEM functions are implemented in XYDRV as a DLL
      (Dynamic Link Library), and are state driven like the Modem I/O
      functions described in the previous section. The TERM program
      provides an example of using XYDRV.

      Files can be sent and received using XMODEM, XMODEM/CRC, XMODEM/1K,
      and YMODEM. The basic procedure used to run XMODEM or YMODEM is as
      follows:

      (1) Call xyAcquire() immediately after calling SioReset().

      (2) To receive a file, call xyStartRx(), then call xyDriver()
          repeatedly until XY_IDLE is returned.

      (3) To send a file, call xyStartTx(), then call xyDriver() repeatedly
          until XY_IDLE is returned.

      (4) Call xyRelease() immediately before calling SioDone().

      Refer to the TERM program for examples of calling the XYDRV
      functions.

      5.2 XYDRIVER Function Summary

             xyAbort : Abort driver at any time.
           xyAcquire : Acquire a port.
             xyDebug : Set the debug level.
            xyDriver : Executes the next state or states.
        xyGetMessage : Get the next debug message.
      xyGetParameter : Get a driver parameter.
       xyGetFileName : Get name of file being sent or received.
           xyRelease : Release a port.
      xySetParameter : Set a driver parameter.
           xyStartRx : Start a receive.
           xyStartTx : Start a transmit.

      Refer to the WSC4VB Reference Manual (WSC4VB_R.TXT) for more detailed
      information.















     WSC4VB Users Manual                                       Page 9

      6.0 ASCII File Transfer

      6.1 ASCII Protocol

      The "ASCII Protocol" is not a defined protocol, but rather it is a
      loose set of conventions developed over a period of years by BBS
      operators. Because XON/OFF flow control is used, only ASCII text can
      be transferred. The ASCII protocol is implemented as a DLL and is
      state driven like the MIO and XYDRIVER code.

      (1) Call ascInit(Port,RxQueSize,xFlag) to do initialization, where

            Port = The connected port (COM1, COM2, etc).
       RxQueSize = The size of the Rx Queue as passed to SioReset().
           xFlag = 1 if this module will perform XON/XOFF flow control.
                   Set to FALSE if flow control is being performed by the
                   WSC code (you called SioFlow()).

      (2) To send an ASCII file, call

      ascStartTx(FileName,CharPace,TermChar,EchoFlag), where
         FileName = The path & name of the file to send.
         CharPace = The delay in milliseconds between characters.
         TermChar = The termination character to send after the file
                    has been sent. If none, use 0x00.
         EchoFlag = 1 if screen echo is desired.

      Then call ascDriver() until it returns IDLE (1).

      (3) To receive an ASCII file, call

      ascStartRx(FileName,TermChar,FirstWait,CharWait,EchoFlag), where
         FileName = The path & name of the file to send.
         TermChar = The termination character. If none, use 0x00.
        FirstWait = The maximum number of seconds to wait for the
                    first incoming character.
         CharWait = The maximum number of seconds after which it is
                    assumed that the other side has completed sending.
                    If unsure, set this to 3 seconds.
         EchoFlag = 1 if screen echo is desired.

      Then call ascDriver() until it returns IDLE (1).

      6.2 ASCII Function Summary

             ascAbort : Abort driver at any time.
            ascDriver : Executes the next state or states.
        ascGetMessage : Get the next debug message.
      ascGetParameter : Get a driver parameter.
       ascGetFileName : Get name of file being sent or received.
              ascInit : Initialize the driver.
           ascStartRx : Start a receive.
           ascStartTx : Start a transmit.





     WSC4VB Users Manual                                       Page 10

      7.0 Problems

      If you cannot get your application to run properly, first compile and
      run the example program EASY.BAS. Test EASY by connecting two
      computers with a null modem cable or by connecting a modem to a
      serial port.

      Once EASY runs, compile and run the SELFTEST program.  This program
      will test your serial ports' functionality.

      If your application does not run but EASY and SELFTEST run correctly,
      then you have most likely made a programming mistake in your
      application. MarshallSoft Computing cannot debug your application,
      especially over the telephone!  However, consider each of the
      following when searching for an error in your application.

      1.  Have you included the file WSC32.BAS in your application ?

      2.  Are your receive and transmit buffers large enough ? Use a buffer
      size that is twice the size of the largest expected block.

      3.  Have you selected too high a baud rate? Windows can multitask
      many tasks at once. You may have to lower your baud rate (or get
      16550 UARTS).

      4.  Did SioReset return a zero value ?  If not, then you must call
      SioReset again. See EASY.BAS for an example.

      5.  Did you send the proper initialization string to your modem ?
      Did you set DTR and RTS? (you should).

      7. Are you trying to link a 32-bit DLL to a 16-bit program (or vice
      versa)? The typical error message refers to a "corrupted" DLL file.

      Keep Win16 & Win32 development separate.

      We recommend the following steps if you believe that you have
      discovered a bug in the library: (1) Create the smallest, simplest
      test program possible that demonstrates the problem.  (2) Document
      your exact machine configuration and what error the test program
      demonstrates.  (3) Email us the example source.

      If the problem can be solved with an easy work-around, we will
      publish the work-around.  If the problem requires a modification to
      the library, we will make the change and make the modified library
      available to our customers without charge.












     WSC4VB Users Manual                                       Page 11

      8.0 Example Programs

      The example programs are designed to demonstrate the various
      capabilities of WSC4VB. The best way to become familiar with WSC4VB
      is to study and run the example programs.

      8.1 EASY

      EASY is a very simple communications program using WSC4VB. Everything
      that is typed on the keyboard is sent to the serial port, and
      everthing incoming from the serial port is displayed on the screen.

      The easiest way to test EASY is to connect to a modem.  Typing 'AT'
      should result in an 'OK' being displayed.

      A null-modem cable can also be used to connect two computers together
      with their serial ports. Run EASY on both machines. Whatever is typed
      on one machine will be displayed on the other.

      8.2 SELFTEST

      SELFTEST performs a serial port I/O functionality test. Either a pair
      of ports on the same computer (using a null modem cable) or a single
      port (using a loopback adapter) can be tested.

      Refer to LOOPBACK.TXT for an explanation of how to make a loopback
      adapter (without tools!).

      8.3 MODEM

      MODEM is similiar to EASY, but with enhanced capability. It can set
      flow control (hardware, software, or none), DTR line (set or clear),
      RTS line (set or clear), display the transmit & receive queue sizes,
      detect a break signal, detect changes in DSR and CTS, as well as
      check for various line errors (parity error, framing error, data
      overrun, receive queue overflow, and transmit buffer full).






















     WSC4VB Users Manual                                       Page 12

      8.4 TERM

      TERM is a simple terminal emulator suitable for calling up a BBS and
      downloading or uploading files using XMODEM or YMODEM. The TERM
      program uses MIO.DLL for modem control commands, ASDRV.DLL for the
      ASCII protocol, and the XYDRV.DLL for XMODEM & YMODEM protocol.

      Selecting 'Dial' from the menu bar will result in a pop-up dialog
      requesting the phone number to dial. Once entered, the number is
      dialed, and the program will wait for up to 60 seconds for the
      'CONNECT' string from the modem.  This wait can be terminated at any
      time by choosing 'BREAK' on the menu bar.

      Once logged on, files can be uploaded or downloaded by selecting
      'Send' or 'Receive' from the menu bar. To abort a file transfer,
      choose 'BREAK' from the menu bar then type a series of Ctrl-X (^X)
      characters from the keyboard.

      8.5 FINDER

      The FINDER program searches for a connected modem. Your modem must be
      connected to one of COM1, COM2, COM3, or COM4, and must be turned on.

      FINDER takes no arguments. After connecting your modem to one of your
      serial ports, type

         FINDER