home
***
CD-ROM
|
disk
|
FTP
|
other
***
search
/
User's Choice Windows CD
/
User's Choice Windows CD (CMS Software)(1993).iso
/
win_u_z
/
winprob.zip
/
WIN11.PRB
< prev
next >
Wrap
Text File
|
1990-11-19
|
3KB
|
79 lines
Q65435 High-Speed Communication in Windows 3.00 Enhanced Mode M
Microsoft Windows 3 Retail Product (WIN3)
3.00
MS-DOS
Summary:
You may need to adjust settings in an application's PIF file or the
SYSTEM.INI file to run high-speed data transfers with Microsoft
Windows version 3.00 in enhanced mode. To adjust settings for a PIF
file, do the following:
1. Start PIF Editor.
2. Open the PIF file for editing.
3. Choose the Advanced options.
4. Verify that the Lock Application Memory box is checked.
In the SYSTEM.INI file, you may want to adjust the COMBoostTime,
COMxBufffer, and COMxProtocol, where the x refers to the COM port
number. For example, you would use COM1Buffer and COM1Protocol for
high-speed communications on COM1. These settings are in the [386Enh]
section of the SYSTEM.INI file and can be edited with a text editor
such as Notepad.
More Information:
These lines control the behavior of DOS communication applications
under Windows. Windows 3.00 acts as an interrupt handler for the UART
(Universal Asynchronous Receiver Transmitter). When a character is
received, Windows places it into a buffer until the DOS application is
active. The Windows default buffer size is 128 characters. At high
speeds, these 128 characters go very fast. Setting this buffer to
higher values such as 1024 will enhance communications performance.
The COMBoostTime can specify the amount of time, in milliseconds, for
a virtual machine to process a COM interrupt. When a communication
application is losing keyboard characters on the display, you may want
to increase this value. The default is two milliseconds. For example,
to set the COMBoostTime to 10 seconds, add the line COMBoostTime=10 to
the [386Enh] section of SYSTEM.INI file.
The COMxBuffer specifies the number of characters that will be
buffered by the device on the corresponding communications port.
Before changing one of these settings, verify that the
corresponding COMxProtocol setting has the correct value.
Buffering may slow down communications on a port, but may be
necessary to prevent some communications applications from losing
characters at high baud rates. The size of this buffer will
depend on the speed of the machine and the applications needs.
For example, to set the COM1Buffer to 1024, add the line
COM1Buffer=1024 to the [386Enh] section of the SYSTEM.INI file.
The COMxProtocol specifies whether Windows in 386 enhanced mode should
stop simulating characters into a virtual machine after the virtual
machine sends an XOFF character. If the communications application
using the port is losing characters while doing text transfers at high
baud rates, set the value for a port to XOFF. For example, to set the
COM1Protocol to XOFF, add the line COM1Protocol=XOFF to the [386Enh]
section of the SYSTEM.INI file.
These techniques have been tested to successfully perform
Kermit file transfers at 19200 via a ROLM PBX (100-percent clean
connection).
Tip for Kermit Users
--------------------
The TIMER should be shut off on the side running under Windows. The
Kermit Protocol states that after the start of a packet is received,
there cannot be more than about one second between characters. This
may be a problem at times due to intermediate buffering. Shutting the
timer off does not cause any problems.
COPYRIGHT Microsoft Corporation, 1990.
Updated 90/11/17 06:35