Info-IBMPC@B.ISI.EDU (Info-IBMPC Digest) (09/05/86)
Info-IBMPC Digest Thursday, September 4, 1986 Volume 5 : Issue 82 This Week's Editor: Phyllis O'Neil Today's Topics: PC XT 286 PCjr 640k Internal Memory ADD-ON PC-Kat Device Drivers Re: Graphics Software Package Query More on COMx Interrupt Handling (and Other Topics) Yet More on Asynchronous Interrupts Today's Queries: Quick Basic & DOS 2.11 Path Builder Available? ---------------------------------------------------------------------- Date: Tue, 2-Sep-86 21:05:24 EDT From: David Farber <farber%pcpond.pc.udel.edu@Louie.UDEL.EDU> Subject: PC XT 286 To: ud-ibmpc@louie.udel.EDU ... The new IBM Personal Computer XT Model 286 combines the cost effectiveness and flexibility of a Personal Computer XT with the high-speed, high-performance technology of the Intel 80286 microprocessor. The IBM Personal Computer XT Model 286 can operate up to three times faster than earlier models of the Personal Computer XT in most applications and comes standard with 640 kilobytes of memory. Various memory expansion options allow users to increase memory up to 12.6 megabytes. Standard features of the new system include a half-high, 1.2 MB, 5 1/4-inch, double-sided diskette drive, a 20 MB fixed disk drive, a serial/parallel adapter card and the IBM Enhanced Personal Computer Keyboard. An optional second diskette drive may be selected from the following offerings: -- A half-high, double-sided 3 1/2-inch, 720 KB internal diskette drive priced at $190-a. This drive also is available for installation in the IBM Personal Computer AT (R) Models 319 and 339. The diskette drive allows exchange of data between the IBM Personal Computer AT, the IBM Personal Computer XT and the IBM PC Convertible. -- A half-high, 5 1/4-inch, double-sided diskette drive with 1.2 MB of storage capacity, priced at $275. -- A half-high, 5 1/4-inch, 360 KB, double-sided diskette drive, priced at $225. The new computer also supports the IBM Personal Computer 3 1/2-inch External Diskette Drive. This enables users to exchange information between the IBM Personal Computer XT Model 286 and the IBM PC Convertible. The IBM single unit price for the new Personal Computer XT Model 286 is $3995. It is available now through Authorized IBM Personal Computer Dealers and IBM branch sales offices. IBM Personal Computer XT System Board Enhancement IBM also announced an enhancement to the two 20 MB fixed disk drive models of the Personal Computer XT (Models 088 and 089), increasing their standard system board memory to 640 KB from 512 KB with no change in price. Tape Backup Program for IBM Personal Computers IBM today introduced a software package to facilitate tape backup for IBM Personal Computers. SY-TOS (TM) Tape Utilities is designed to work with the IBM 6157 Streaming Tape Drive to provide an easy-to-use, versatile tape backup system for the IBM Personal Computer, Personal Computer XT, Personal Computer AT, 3270 Personal Computer, 3270 Personal Computer AT and Personal Computer XT Model 286. The program supports file, partition or entire disk backup and restore. The IBM single unit price for SY-TOS Tape Utilities is $70. It will be available this month from Authorized IBM Personal Computer Dealers and IBM marketing representatives. Educational Software IBM also announced nine new educational software programs for use by students 1/4 IBM Personal Computers: three programs in the IBM Personal Computer Punctuation Series; three programs in the IBM Personal Computer Combining Sentences Series; two programs in the IBM Personal Computer Geometry Series and the Introduction to General Chemistry, a vendor-logo program. The Punctuation Series helps students learn correct punctuation and capitalization skills. Available next month in three levels and designed for students in grades 3 through 8, it has a one-time license charge of $110 (single pack) or $475 (school pack), per level. The Combining Sentences series is designed to develop sentence structure and compositions skills. Also available in three levels, it has a one-time license charge of $110 (single pack) or $495 (school pack), per level, and will be available next month. In the Geometry Series, students build an understanding of relations and concepts in plane geometry. The program will be available in November 1986 for a one-time license charge of $195 (single pack) or $975 (school pack) for each of two levels. Introduction to General Chemistry uses simulated experiments with color graphics and animation to help students gain experience in collecting and interpreting data. The starter set has a one-time license charge of $590, with additional student sets available for $150. The network version, which supports all users in a network, is $1,770. All three versions will be available this month. IBM PC Convertible Speech Adapter IBM also announced an optional speech adapter for the IBM PC Convertible. Designed primarily for education applications in kindergarten through 12th grade, the IBM PC Convertible Speech Adapter lets the computer "talk" to children as they use interactive education programs such as IBM Personal Computer Writing to Read (R) Version 3.0. The IBM PC Convertible Speech Adapter will be available in the fourth quarter of 1986 through IBM marketing representatives and Authorized IBM Personal Computer Dealers. IBM's single unit price for the product is $495. -All prices shown are IBM single unit prices for products purchased directly from IBM. Dealer prices may vary. Personal Computer AT and Writing to Read are registered trademarks of International Business Machines Corporation. SY-TOS is a trademark of Sytron Corp. ------------------------------ Date: Tue, 2 Sep 86 18:32:49 pdt From: Ernie Meri <hoptoad.UUCP!leadsv!meri@cgl.ucsf.edu> Subject: PCjr 640k Internal Memory ADD-ON To: info-ibmpc%usc-isib.arpa@cgl.ucsf.edu There is a product available from : ES Quality Products 5311 Mango Blossom San Jose, Ca 95123 (408) 224-5574 that not only can expand your internal memory to 384 or 640k (without additional power supplies or sidecars), but will accelerate mpu performance double that of a standard PCjr. The plug-in card inserts into the 8088 mpu header inside the PCjr and costs approximately $120.00 (less memory chips). I have been using the "jr HOTSHOT" for six months, with excellent results with all the common database and spreadsheet programs, plus keeping side-kick and lightning resident. The only drawback is using cartridge BASIC, (it does not recognize the extra memory), and then you must reboot the software to the "standard" configuration or get a hold of a copy of GW Basic (which will run fine as long as you don't ask for screen 4-6 or other PCjr unique features). Since most of my work doesn't depend on cartridge BASIC, this is a real boon in getting performance out of the Jr - plus they offer a 2 YEAR guarantee on the "HOTSHOT" card. ------------------------------ Date: 3 Sep 1986 09:08:30-EDT From: mlsmith@NADC To: jshaver@apg-3.arpa Subject: PC-Kat Cc: info-ibmpc@usc-isib I was quite impressed with PC-Kat until I took a good look at the listings. They were wrong!!! PC-Kat does not seem to understand DOS 3.X FATs. It gets lost when the directory files are split across the disk. I do not know if there is a critical distance or if any split will do this. The effect is that the last file found before the split is repeated for all subsequent files. If anyone has a working version for DOS 3.X, please send it to pc-blue. mlsmith@nadc ------------------------------ Date: 3 Sep 1986 09:20:21-EDT From: mlsmith@NADC To: cbsoth@brl Subject: Device Drivers Cc: info-ibmpc@usc-isib A good example of a driver that can be included in config.sys or executed as a program is mouse.sys and mouse.com. The difference is where the program is loaded. Mouse.sys is added to config.sys and is oriented to those people that always want the mouse loaded. Mouse.com is for those that only use the mouse rarely or have some resident software that interferes with config.sys operation. {Mouse.sys/com are trademark software of Microsoft} ------------------------------ Date: Wed, 3 Sep 86 11:58:49 PDT From: Jim Anderson <bilbo.jta@LOCUS.UCLA.EDU> To: info-ibmpc@b.isi.edu Subject: Re: Graphics Software Package Query I don't know if they are still in business, but you might look at MetaWindow from MetaGraphics. I don't have their address handy, but the product was mentioned as product of the month in PC Tech Journal a few months back and they did advertize in PC Tech Journal and several other magazines about that time. If you are interested in contacting them and cannot find them send me some mail and I will try to find the address. I was using the package a few months back in beta form. The major deficiency of the package was lack of support for hard copy devices. It included support for all common (and some uncommon) display boards including EGA. It used table driven display algorithms and had facilities for user supplied tables to support display devices other than the built in ones. There were no external device drivers as in Halo. The package was very fast. They had a bulletin board system for support. The licensing agreement seemed far too liberal. If you bought the package for somewhere between $50 (Turbo Pascal) and $150 (several different languages) you could include it in products with no royalty. I too have tried to deal with Media Cybernetics, and cannot understand their pricing. ------------------------------ Date: Thu, 4 Sep 86 10:07:32 EDT From: Jordan%UMass.BITNET@WISCVM.WISC.EDU (Kevin Jordan (413) 545-2690) Subject: More on COMx interrupt handling To: info-ibmpc@b.isi.edu In addition to the comments which have already been made on this subject, there are a couple of very subtle characteristics of the 8250 that you need to watch out for. When writing your own asynchronous interrupt handler for the 8250, your interrupt handler should always read the IIR (Interrupt Identification Register) to determine the source of interrupt. If you read between the lines of the IBM Technical Reference, you will see that one possible source of interrupt is the IIR register itself. When the IIR register is a source of interrupt, the IIR register will contain the value 2. This is the same value contained by the IIR register when the Transmitter Holding Register is a source of interrupt. The only way to distinguish between these two possible sources of interrupt is to interrogate the Line Status Register to see if the Transmitter Holding Register is indeed empty. If you fail to do this, your interrupt handler may make the false assumption that the THR is empty when it is not. This may cause some characters to be lost on output. When the IIR itself is a source of interrupt, the act of reading the IIR cancels that interrupt source, so no further action needs to be taken if your interrupt handler determines that the THR is busy (the THR was not the source of interrupt). Another thing to be careful of is that your interrupt handler should not immediately exit after processing one interrupt. Instead, it should branch back to a point of beginning and re-examine the IIR register in case more than one interrupt is pending. If you fail to do this on some PC models, some interrupts appear to be lost. The 8250 or clone on some models does not seem to re-issue an interrupt request when it has more than one interrupt pending. These words of wisdom have been born of experience. Not all PC models behave the same way with respect to programming the 8250. On some models, the PC/AT for example, the IIR register itself never seems to be a source of interrupt. On the PC/XT, however, it is a source of interrupt. Conversely, it does not seem to be necessary to re-examine the IIR register after processing one interrupt on the XT. It is, however, necessary on the AT. If you follow these guidelines and program your 8250 interrupt handler accordingly, your handler should work properly on all models. If you fail to follow these guidelines, it may only work properly on one model, or on a small cross section of PC clones. ------------------------------ Date: Thu, 4 Sep 86 22:05 EDT From: Hess@MIT-MULTICS.ARPA Subject: More on Asynchronous Interrupts To: INFO-IBMPC@B.ISI.EDU Re: Andrew J. Thomas: More on Asynchronous Interrupts Suggest *not* setting *both* OUT1 and OUT2. Why? Well, if you look at the schematic for the IBM boards, you'll see that only one of them is actually wired to anything which would allow/disallow interrupts. The other one goes nowhere. (I think, but am not sure, that OUT2 is wired, and OUT1 is useless -- but I don't have my manual here...) The other one is, alas, used in an incompatible way by some modem manufacturer somewhere. For instance, the Qubie internal modem card uses the other line to mean modem-reset, which clicks the speaker, temporarily de-asserts the lines, etc. The effect of trying always to put both lines high on that card is to just make a small continuous clicking sound and prevent the card from working. Now, it's not at all compatible with IBM's, but both are not necessary for IBM's, so you might as well only do one of them. Re: Sperry IT (AT clone) and add-on 360K drives We purchased a Toshiba 360K drive for our Sperry IT. It failed to work, by only being able to format the outer tracks of a disk. Another replacement Toshiba drive failed in the same manner. But the Toshiba drive works just fine in a genuine IBM AT. We bought Mitsubishi (what Sperry uses in their original equipment) instead and it worked just fine. Just to let y'all know... Re: 12 MHz AT (PC's Limited) Query? Does anybody actually *have* one of these beasties? Does it run as fast as they say? Does it clone properly? Does the AST Aadvantage card with 100ns memory chips perform with 1 wait state respectably? Is the disk controller fast enough that it's not a system bottleneck? Does it really work? Fast? Brian (Hess@MIT-Multics.Arpa) ------------------------------ Date: 3 Sep 1986 08:02:15 CDT Subject: Quick Basic & DOS 2.11 From: Walt Livingston <DSDC-SDT2@GUNTER-ADAM.ARPA> To: info-ibmpc@B.ISI.EDU I have a problem that someone out there might be able to help me on, especially MicroSoft. Using a TANDY 1200 HD (XT compatible with 640K) and MS-DOS 2.11. hen executing programs compiled as .EXE files (using BRUN20.EXE runtime module) with MicroSoft's Quick Basic V2.0, and going from one program to another with the "RUN filespec" command without exiting to DOS, eventually gets a "Program Too Large" 9error message. This indicates that memory is not being released by the previous program(vs). Two of the programs had built-in "SHELL" state- ments. When these were used to execute the RAM command, it showed that I had a 516K system instead of a 640K system. The next time I used the RAM command it showed that I had a 392K system; i.e., 124K chunks are missing. I looked at locations 0040:0013-14 and it showed 640K as it should. To get around the "Program Too Large" message, I changed the programs to CHAIN instead of RUN. This solved that problem. However, the SHELL statements hang the machine if executed from within a program that was CHAINed to; i.e., if that program is executed directly from DOS, SHELL works correctly. Both of these problems have been duplicated on other hardware, so I know it's not "TANDY" incompatibility. Any assistance from anyone would be greatly appreciated. Walt Livingston DSDC-SDT2@GUNTER-ADAM ------- ------------------------------ To: INFO-IBMPC@USC-ISIB.ARPA From: "Roger Fajman" <RAF%NIHCU.BITNET@WISCVM.WISC.EDU> Date: Wed, 0>3 Sep 86 21:07:20 EDT Subject: Path Builder Available? Does anyone know of a program that can be used in a batch file to search the AUTOEXEC.BAT file for a PATH command, check that PATH command for the presence of a particular directory, and add the directory to the PATH command if it is not already there? The idea is to use such a program in an automatic installation batch file for a piece of software. ------------------------------ End of Info-IBMPC Digest ************************ -------