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- WNTERM
-
- A Simple Windows Terminal Program
-
- William S. Hall
- 3665 Benton Street, #66
- Santa Clara, CA 95051
-
-
- Introduction
-
- WNTERM is a dumb terminal program written for Microsoft
- Windows. The purpose of the program is educational and it is
- distributed with source code. No attempt has been made to add
- features such as memory paging, clipboard data exchange, or smart
- terminal emulation. The primary goal is to show how to use the
- Windows communications features and to illustrate subclassing and
- font enumeration. However, the program functions quite
- adequately as a means for basic communication with another
- computer through the serial port.
-
- WNTERM has a useful option allowing you to choose a font
- which will provide the maximum number of visible lines on the
- screen. One possible application is to use WNTERM as a debugging
- terminal. See the sections below on selecting a small font and
- the caveats about maximum baud rates.
-
-
- Program Operation
-
- To use the program, copy WNTERM.EXE to an appropriate
- directory and run it under Windows. The program first tries to
- open COM1. If not successful, it tries COM2. If this fails, the
- program exits. if a port can be opened, the baud rate, parity,
- and word size will be set according to the COMx: strings in the
- [ports] section of win.ini. You should modify these values (use
- the Control Panel) if to do so does not interfere with a serial
- printer setting. Otherwise, you can set the desired parameters
- with the program's 'Communications' menu.
-
- When the window appears, the program will be ready to
- communicate with the port shown in the title bar. You can switch
- between line and local operations by toggling the 'Line/Local'
- menu item. At any time, you can clear the screen with the
- 'ClearScreen' menu choice. If needed, Local Echo can be
- selected. Scrolling can be started and stopped with the Scroll
- Lock key.
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- Using a Small Font
-
- After the program has run for the first time, an entry is
- made in win.ini of the form:
-
- [Wnterm]
- SmallFont=0
-
- If you change 0 to 1, the program will search all Courier fonts
- installed on your system for the one with the smallest height.
- If one is found with a height less than and of width less than or
- equal to that of the Windows system font, then the smaller font
- will be used. In this way, it is possible to have more lines on
- the screen. If you install COURA.FON (which is normally copied
- to your Windows directory only if you have a CGA, so you may have
- to retrieve it from the distribution disks), you can have as many
- as 73 lines on a VGA screen and 53 on the EGA. If no small font
- is found, then the system font will be used. You will then have
- a maximum of 29 lines on the VGA and 32 on the EGA. (The EGA
- system font is only 10 pixels high, whereas on the VGA it is 15).
-
-
- Flow Control and Baud Rates
-
- The program needs XON-XOFF on the host side for baud rates
- above 2400. At 2400 baud or below, the performance on a 16 mHz.
- 386 machine is adequate for sustained operation without
- handshaking at full screen. You may have to experiment with
- machines of lower performance to find the maximum usable baud
- rate with no flow control. Generally this is of no concern
- unless the host is incapable of XON-XOFF as might be the case
- when WNTERM is being used as a debugging terminal.
-
-
- Windows Communications Driver
-
- COMM.DRV in most versions of Windows 2.10 will not operate
- correctly with Xon-Xoff flow control. A replacement is provided
- with this program. You will have to reinstall Windows to use the
- new driver. Begin by using Diskcopy to duplicate the diskette on
- which the old COMM.DRV file is located. Replace COMM.DRV with
- the new version. Now run Windows Setup with the modified
- diskettes.
-
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- Source Code
-
- The source code is enclosed on the disk. If you know
- Windows programming, it should not be too difficult to read. If
- you do not, watch Programmer's Journal for an article based on
- this program.
-