Simtel MSDOS 1992 June

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Text File | 1989-04-20 | 17.7 KB | 365 lines

------------------------------------------- For personal, noncommercial use only May not be sold - All rights reserved ------------------------------------------- Copyright (C) 1988, 1989 by FM de Monasterio BLANKs version 1.6b -------------------- BLANKs is an MS-DOS/PC-DOS based, resident program that blanks the screen after a preselected interval in the absence of a keypress. This interval can be selected from 1 to 60 minutes. A selection higher than 60 minutes is set to 60. Selecting 0 minutes disables screen blanking; blanking can be enabled by re-invoking with an interval of 1 to 60 min. BLANKs is a TSR. When resident, it uses less than 700 bytes; it can be invoked repeatedly to change its settings without resulting in multiple copies to memory. BLANKs intercepts interrupts 8h, 9h, and 10h, and is a well behaved resident, intended to run under MS-DOS or PC-DOS version 2.0 or later. ---------------- OPERATION: Screen blanking is obtained by direct commands to the hardware (video controller) to turn off/on the video signal. This is a fast method that operates successfully in the IBM PC/XT, PC/AT and in some IBM compatible computers installed with MDA, CGA, EGA, VGA, and Hercules video adapters or with IBM compatible adapters from other manufacturers. NOTICE In some nonIBM microcomputers the program may not work and it ------ should NOT be used with other video adapter types unless they are compatible with the IBM adapter at the register level (as it is possible that some of these adapters might be damaged). The resident component of BLANKs intercepts interrupts 8, 9, 10h and 33h that subserve respectively the time-of-day, keyboard, BIOS video and (for programs following the Microsoft's Mouse format) mouse operations. BLANKs will fail to operate if access to interrupts 8 and 9 is denied by another program or resident loaded after BLANKs. This might occur with a few communication and (older) word processing programs. - Interrupt 8 is called 18.2 times/s to update the computer time-of-the-day counter (which is stored in the BIOS data area). Since a timer interrupt can thus only operate within a period of about 55 ms or less (*including* the overhead of DOS and other programs hooking on the timer), the program uses direct commands to the hardware, written in assembly language, which are issued (when needed) after the original timer interrupt is served. - Interrupt 9 is called when a key on the keyboard is pressed (or released). When the hotkey service is enabled (see switch /H below), BLANKs triggers blanking of the screen when the default hotkey combination (CTRL-B in non- shareware versions) is pressed. The hotkey code is then removed from the keyboard buffer. Other keys are passed along for keyboard processing and, if a blanking had occurred, the screen is restored. - Interrupt 10h is called to mediate a number of video subfunctions. Because such functions are comparatively slow, many programs do not use BIOS video calls, but make direct writes to the screen (which are not detected by the resident part of BLANKs). - Interrupt 33h is used in Microsoft's implementation of calls to the Mouse. Other drivers, compatible with the Microsoft Mouse format, also implement at least some of these calls. Some graphics programs, however, do not use these calls, and their resulting video activity is not detected by BLANKs. NOTICE To be able to monitor interrupt 33h, BLANKs must be installed ------ *after* the mouse driver program as otherwise the driver will not allow access to the interrupt. Also note that the driver for a well known mouse, upon its installation, can freeze the computer if interrupt 33h is found to be in use; this problem does not occur with other drivers, e.g. Logitech's MOUSE.COM. Bypassing Interrupts: While installed, BLANKs bypasses the interrupt 8 when a blanking interval of 0 minute has been selected (see below). Interrupt 9 is bypassed only when both an interval of 0 minute and the switch /H- (see below) have been selected. When /H- has been selected along with a nonzero interval, just the hotkey service of interrupt 9 is bypassed. Hence, these two interrupt activities of BLANKs are bypassed by the "0 /H-" selection; this may be of use in case of testing potential conflicts with other programs. Interrupts 10h and 33h are not intercepted when "/K[+]" is specified; when this switch is not specified, these two interrupts are intercepted but not monitored unless the switch "/V[+]" is specified. (In the shareware version, where cloning is available, if a cloned version has been created with /K+ as the default condition, these 2 interrupts are bypassed irrespective of whether switches "/K-" and/or "/V+" are specified or not. To access video activity monitoring, the program must be recloned with a command line including the "/K- /C" switch selections.) ---------------- USAGE: From the DOS command line or from a batch file, BLANKs is installed (or, when already installed, modified) by the command: BLANKs [?] [min] [/switches] [?] Invokes a brief help and status display, identifying the type of adapter for which the program is configured, the current adapter, and program settings (if installed). Pressing key <F1> displays further help on using the program. If the program has not been installed, pressing key <D> shows the default settings. [min] Timed blanking interval in minutes. These are the minutes that the program waits before blanking the screen in the absence of keyboard activity. Valid selections are 0 or a number in the range of 1 to 60. The selection of a 0-min interval disables the timed blanking of the screen; the selection of an interval larger than 60 defaults to 60 minutes for 2 digit inputs or to the value (in the valid range) of the first 2 digits in inputs containing larger numbers. Null interval defaults to 3 minutes. This value may be changed by cloning the program (see below). Several switches are recognized. While shown as being preceded by a "/" for the sake of clarity, the program accepts any character between space [ ] and slash [/] as a switch delimiter [!"#$%&'()*+,-.]. Nonrecognized switches abort loading of the program. Switches are not case sensitive. NOTE: Options marked with an asterisk (*) are available in the shareware versions of BLANKs only. /U Uninstall. Use only when BLANKs was the last resident to be installed, as otherwise this would create a "hole" in memory. The request is not honored if vectors to interrupts 8, 9 and 10h have been changed since installation. This can be caused by a resident installed after BLANKs, or by a prior resident that changes vectors set by programs installed after it. You can determine if this is the case by using any of the memory mapping programs that are available (search for interrupts 8 9 and 10; BLANKs.COM will be shown as an unnamed entry using 736 or 656 bytes, depending on the switch selection.) /C Clone to disk the current version of BLANKs installed in the memory.(*) This permits making the settings of this version the default ones. If the /C switch is entered in the command line alone, default parameters do not become effective (unlike the case of any other single switch specification) and the resident parameters are copied to the cloned file. If other switches or parameters are entered along with /C, these new parameters and, when applicable, defaults become effective, and are copied to the cloned file. The clone file BLANKs.COM is written to the default drive and directory. A warning is given if a file with the same name is present there, and the user has the option to overwrite it or to abort the cloning. Cloning will not overwrite files other than those with a normal or archive attribute, or both. /H Hotkey switch. In addition to timed screen blanking, BLANKs allow for manual blanking of the screen by pressing a hotkey combination. This combination is CTRL-B in the nonshareware version of the program (see below). When BLANKs detects the hotkey, it removes it from the keyboard buffer. However, be aware that programs loaded after BLANKs may save this input; this is the case, for instance, with some word processors in which it is necessary to erase the hotkey character from the text. In the shareware version, the hotkey combination can be changed in case of assignment conflicts. /H+ Enable hotkey operation. This is the default condition when an argument is not specified for this switch. /H- Disable hotkey operation. Can be reenabled with /H+. /H? Allow the selection of a different hot-key combination.(*) Valid combinations include an alphanumeric key and one of more of the following shift keys: CTRL, ALT, left-SHIFT, right-SHIFT. For obvious reasons, CTRL or ALT, or both, must be included in the hotkey combination. /Ax Force configuration to specified adapter. This switch bypasses the automatic configuration of the program for the video adapter detected at the time of (each) calling. Valid specifications for this switch are: /Am configuration for the IBM Monochrome Display Adapter (MDA) and Hercules graphics cards (HGA, HGA plus, and In Color); uses and restores bit 3 of the video port 3B8h. /Ac configuration for the IBM Color Graphics Adapter (CGA), the Multi Color Graphics Array (MCGA) and compatibles; uses and restores bits 0-3 of port 3D9h and bit 3 of port 3D8h. /Ae configuration for the IBM Enhanced Graphics Adapter (EGA) and compatibles; reads video ports 3BAh and 3DAh, and uses and restores bit 5 of port 3C0h. /Av configuration for the Video Graphics Array (VGA); uses port 3C4h, and uses and restores bit 5 of port 3C5h. This configuration can be preserved as a default upon cloning of (the shareware version of) BLANKs. Switch /A is useful when the video adapter type is incorrectly identified by BLANKs or when an "unknown" identification result is obtained (see the Help display called by the option "?"). See the above NOTICE on compatibility. -------------------------------------- /V Force monitoring of video activity mediated by BIOS (and DOS) calls to interrupt 10h, and by (Microsoft) Mouse calls to interrupt 33h. If enabled, the switch avoids the timed blanking of the screen when such video activity is detected; the switch is not effective during manual blanking of the screen, however, which can unblanked only by keyboard activity. Notice that the video output of some programs is not made via these interrupts and therefore their activity will not be detected. Some mouse drivers, as noted above, can freeze the machine if they found that interrupt 33h is being used by another utility. Hence, if you you have such a driver and do not want to install it before BLANKs, BLANKs needs to be installed with the "/K[+]" switch or uninstalled before installing the driver and then reinstalled (with the "/V[+]" if desired) via a batch file. /V+ Enable video activity monitoring. This is the default when an argument is not specified for this switch. /V- Disable video activity monitoring. Switch /V is disabled when "/K[+]" (see below) is specified or when a clone with a "/K[+]" default has been created. In the latter case, a new clone with a "/K-" default will have to be created to reenable monitoring of video activity (see Bypassing Interrupts). /K Force monitoring of keyboard activity only. When enabled at the time of installation, this switch installs a shorter resident component of less than 660 bytes that disregards video activity. Because of the potential of hanging the computer if an uninstall request were to be made after a change in the status of this switch, reinvocation of the program ignores all "/K" switch requests, except for cloning purposes (in which case it is not recommended to uninstall the program with the cloned version). NOTE: To change the status of this switch, uninstall BLANKs and then invoke it with the appropriate argument. /K+ Enables monitoring of keyboard activity only. This is the default when an argument is not specified for this switch. When enabled, the status of switch /V is ignored. (Resident = 656 bytes.) /K- Disables exclusive monitoring of keyboard. To also monitor video activity the /V switch must be enabled. (Resident = 736 bytes.) ---------------- RELEASE: The BLANKs utilities and the documentation (the "software") are copyrighted by the author. In the present nonshareware form, they are distributed free of charge for NONCOMMERCIAL PERSONAL USE ONLY. Although the nonshareware version of BLANKs lacks a few of the features noted above, it is a completely usable program. Notice that support is not provided for this version. The shareware versions of the programs cost $7 plus mailing, and can be ordered from the address below (360 kb diskette). Indicate whether an 80286 or an 8086 version is applicable; the 80286 version does not check for CGA "snow." ---------------- LICENSE and INJUNCTIONS The copyright owner hereby licenses you, free of charge, to: 1. Use this software for noncommercial, personal purposes. 2. Make as many copies of the software as desired. 3. Distribute the software including via electronic means. The copyright owner hereby specifically prohibits you from: 1. Charging or asking donations for copies of this software. 2. Distributing the software with commercial products without a written permission from the owner. 3. Distributing the software via a for-profit organization, either alone or with other software. Any other use is prohibited without express, written permission in advance from the copyright owner. ---------------- DISCLAIMER: The author makes no warranty, either implied or expressed, including, without limitation, any warranties with respect to the software documented here, its quality, performance, or fitness for any particular purpose. In no event shall the author be liable for damage, whether direct, indirect, special, incidental, or consequential, that arise from the use of or any defect in the software. The entire risk as to the quality and performance of the software is with the user. By using this program, you acknowledge: (1) to have read and understood all parts of the disclaimer and (2) to have agreed with and accepted all of its provisions. ---------------- Refer all inquiries to: F.M. de Monasterio 7013 Barkwater Ct. Bethesda, Md 20817 Messages may be left at: The DC Information Exchange BBS 202-433-6639 Sysop: Bill Walsh; 2400/1200 bps