[386Enh] Section Settings The [386Enh] section contains information specific to running Windows in 386 enhanced mode, including information used for virtual-memory page swapping. The [386Enh] section can contain the following settings. ____________________________________________________________ AllVMsExclusive= Default: False Purpose: If enabled, this setting forces all applications to run in exclusive full-screen mode, overriding all contrary settings in the applications' program information files (PIFs). Enabling this setting might prolong the length of the Windows session when you are running network and memory-resident software that is incompatible with Windows. ____________________________________________________________ COMBoostTime= Default: 2 Purpose: Specifies the amount of time (in milliseconds) to allow a virtual machine to process a COM interrupt. If, while running a communications application, you lose keyboard characters on the screen, you can try increasing this value. ____________________________________________________________ COMdrv30= Default: False Purpose: If enabled, the Virtual COM Driver (VCD) uses its own copy of the interrupt handler for the serial communications driver. This improves performance of your COM ports. Enable this setting if you are using a Windows version 3.0 serial communications driver. Disable this setting if you are using the standard Windows 3.1 serial communications driver. ____________________________________________________________ COM1FIFO= COM2FIFO= COM3FIFO= COM4FIFO= Default: True Purpose: Specifies whether the FIFO buffer of a COM port's 16550 Universal Asynchronous Receiver Transmitter (UART) should be enabled (True) or disabled (False). If a serial port does not have a 16550 UART, this setting is ignored. Note: These values are used by Windows for both standard and 386 enhanced modes. ____________________________________________________________ COMIrqSharing= Default: True for Micro Channel and EISA machines; False for all other machines. Purpose: Specifies whether COM interrupt lines are sharable between multiple serial ports or with other devices. Enable this setting if your machine uses the same interrupt for COM3 or COM4 as it does for COM1 or COM2. ____________________________________________________________ DOSPromptExitInstruc= Default: Yes Purpose: If this setting is enabled, when you start the MS-DOS prompt a message box appears with instructions on how to exit and switch away from the MS-DOS prompt. Disable this setting if you do not want to see the message. ____________________________________________________________ DualDisplay= Default: See "Purpose" below. Purpose: Normally, when running in 386 enhanced mode, the memory between B000:0000 and B7FF:000F is used by the general system unless a secondary display is detected. Enable this setting if you are using a VGA-based color display and want EMM386.EXE to include this address space as an upper memory block (UMB). In addition to enabling this setting, you must include the i= option in the device=EMM386.EXE command line in your CONFIG.SYS file as follows: device=EMM386.EXE i=B000-B7FF If this setting is disabled, the address range is available on EGA systems, but not on VGA systems, because the VGA display device supports monochrome modes, which use this address space. ____________________________________________________________ EMMExclude= Default: None Purpose: Specifies a range of memory that Windows will not scan to find unused address space. This has the side effect of turning off the RAM and ROM search code for the range. The range (two paragraph values separated by a hyphen) must be between A000 and EFFF. This scanning can interfere with some adapters that use the same memory area. The starting value is rounded down and the ending value is rounded up to a multiple of 16K. For example, you could set EMMExclude=C800-CFFF to prevent Windows from scanning the addresses C800:0000 through CFFF:000F. You can specify more than one range by including more than one EMMExclude line. ____________________________________________________________ EMMInclude= Default: None Purpose: Specifies a range of memory that Windows will treat as unused address space regardless of what may be there. EMMInclude takes precedence over EMMExclude if you specify ranges that overlap. The range (two values separated by a hyphen) must be between A000 and EFFF. The starting value is rounded down and the ending value is rounded up to a multiple of 16K. For example, you could set EMMInclude=C800-CFFF to ensure that Windows can use the addresses C800:0000 through CFFF:000F. You may specify more than one range by including more than one EMMInclude line. ____________________________________________________________ EMMPageFrame= Default: None Purpose: Specifies the starting paragraph where the 64K page frame will begin when Windows (running in 386 enhanced mode) cannot find a suitable page frame. Allows an EMM page frame in an area containing some unused RAM or ROM. For example, you could set EMMPageFrame=C400 to start the page frame at C400:0000. ____________________________________________________________ EMMSize= Default: 65536 Purpose: Specifies the total amount of memory available for mapping as expanded memory. The default value allocates the maximum possible amount of system memory as expanded memory. Specify a value for this setting if you run an application that allocates all of the available expanded memory. If this is the case, you cannot create new virtual machines. If this value is zero, no expanded memory is allocated, but the EMM driver will load. To disable EMM and prevent the EMM driver from loading, use the NoEMMDriver setting. ____________________________________________________________ FileSysChange= Default: Off in 386 enhanced mode; not supported in standard mode. Purpose: Indicates whether File Manager automatically receives messages anytime a non-Windows application creates, renames, or deletes a file. If this setting is disabled, a virtual machine can run exclusively, even if it modifies files. Enabling this setting can slow down system performance significantly. ____________________________________________________________ InDOSPolling= Default: No Purpose: If enabled, prevents Windows from running other applications when memory-resident software has the InDOS flag set. Enabling this setting is necessary if the memory-resident software needs to be in a critical section to do operations off an INT21 hook, but will slow down system performance slightly. ____________________________________________________________ INT28Critical= Default: True Purpose: Specifies whether a critical section is needed to handle INT28h interrupts used by memory-resident software. Some networks do internal task switching on INT28h interrupts. These interrupts might lock up some network software, indicating the need for an INT28h critical section. If you are not using such software, you might improve Windows task switching by disabling this setting. ____________________________________________________________ LocalReboot= Default: On Purpose: Specifies whether you can press CTRL+ALT+DEL to quit applications that cause an unrecoverable error in 386 enhanced mode. If this setting is enabled, you can quit the applications without restarting Windows. If this setting is disabled, pressing CTRL+ALT+DEL will restart your entire system. ____________________________________________________________ MaxCOMPort= Default: 4 Purpose: Specifies the maximum number of COM ports supported in 386 enhanced mode. Change this value if you have more than four COM ports installed in your computer. ____________________________________________________________ NetAsynchFallback= Default: False Purpose: If this setting is enabled, Windows attempts to save a failing NetBIOS request. When an application issues an asynchronous NetBIOS request, Windows attempts to allocate space in its global network buffer to receive the data. If there is insufficient space in the global buffer, Windows typically fails the NetBIOS request. If this setting is enabled, Windows attempts to save such a request by allocating a buffer in local memory and preventing any other virtual machines from running until the data is received or the timeout period (specified by the NetAsynchTimeout setting) expires. ____________________________________________________________ NetAsynchTimeout= Default: 5.0 Purpose: Specifies the timeout period (in seconds) when Windows will enter a critical section in order to service an asynchronous NetBIOS request. It is used only when the NetAsynchFallback setting is enabled. This value can include a decimal (such as 0.5). ____________________________________________________________ NetDMASize= Default: 32 on Micro Channel machines (IBM PS/2 or compatible); 0 on non- Micro Channel machines (IBM PC/AT or compatible). Purpose: Specifies the DMA buffer size (in kilobytes) for NetBIOS transport software if a network has been installed. In this case, the buffer size is the larger of this value or the value of DMABufferSize. ____________________________________________________________ NetHeapSize= Default: 12 Purpose: Specifies the size (in kilobytes) of the data-transfer buffers in conventional memory that Windows allocates for transferring data over a network when running in 386 enhanced mode. All values are rounded up to the nearest 4K. ____________________________________________________________ Network= Default: None (Setup assigns an appropriate value based on your system configuration.) Purpose: Specifies the type of network you are using with Windows in 386 enhanced mode. ____________________________________________________________ PSPIncrement= Default: 2 Purpose: Specifies the amount of additional memory, in 16-byte increments, that Windows should reserve in each successive virtual machine when the UniqueDOSPSP setting is enabled. The setting that works best for your machine might vary depending on your memory configuration and the applications you are running. Valid values are 2 through 64. See the UniqueDosPSP setting for more information. ____________________________________________________________ ReflectDosInt2A= Default: False Purpose: Indicates whether Windows should consume or reflect DOS INT 2A signals. The default means Windows will consume these signals and therefore run more efficiently. Enable this setting if you are running memory-resident software that relies on detecting INT2A messages. ____________________________________________________________ SyncTime= Default: True Purpose: If this setting is enabled, Windows periodically synchronizes its time with the computer's CMOS clock. If this setting is disabled, Windows usually maintains the correct time, unless TrapTimerPorts is disabled and you are running applications that can cause the system time to run faster or slower than the actual time. This setting is related to the TrapTimerPorts setting. ____________________________________________________________ TimerCriticalSection= Default: 0 Purpose: Instructs Windows to go into a critical section around all timer interrupt code and specifies a timeout period (in milliseconds). Specifying a positive value causes only one virtual machine at a time to receive timer interrupts. Some networks and other global memory-resident software may fail unless this setting is used. However, using this setting slows down performance and can make the system seem to stop for short periods of time. ____________________________________________________________ TrapTimerPorts= Default: True Purpose: Specifies whether Windows should trap read and write operations to the system timer ports that are performed by applications. If this setting is disabled, Windows will not trap these operations, allowing applications that frequently read or write to the timer to run faster. However, this may interfere with ability of Windows to keep accurate system time. If this setting is disabled, Windows can usually detect when an application has changed the timer interrupt interval and then make any adjustments to the time. If your system's time appears to be running fast or slow, enable this setting. If you do not want to enable this setting, enable the SyncTime setting. This causes Windows to check the time periodically and then make any necessary adjustments. ____________________________________________________________ UniqueDOSPSP= Default: True if you are running a network based on Microsoft Network or LAN Manager. See the NETWORKS.WRI online document to find out whether the network you are running is one of these. False for all other networks. Purpose: If this setting is enabled, Windows starts every application at a unique address (PSP). Each time Windows creates a new virtual machine to start a new application, Windows reserves a unique amount of memory (i bytes) below the application. For example, if the first application is loaded at address M, the second application is loaded at address M+i, the third at M+2i, and so on. The amount of memory (i) is determined by the PSPIncrement setting. These settings ensure that applications in different virtual machines all start at different addresses. Some networks use applications' load addresses to identify the different processes that are using the network. Disabling this setting on such networks might cause one application to fail when you quit another, because the network interprets them as the same application. When this setting is enabled, slightly less memory is available for non-Windows applications. ____________________________________________________________ VirtualHDIrq= Default: On for AT-compatible computers; Off for all other computers. Purpose: If enabled, Windows in 386 enhanced mode can terminate interrupts from the hard disk controller, bypassing the ROM routine that handles these interrupts. Some hard disk drives might require this setting to be disabled in order for interrupts to be processed correctly. If this setting is disabled, the ROM routine handles the interrupts, which slows down system performance. ____________________________________________________________ .