From: Info-IBMPC@wsmr-simtel20.Army.mil ("Info-IBMPC Digest")
Newsgroups: comp.sys.ibm.pc.digest
Subject: Info-IBMPC Digest V93 #13
Date: 27 Jan 93 12:25:34 GMT
Reply-To: Info-IBMPC@wsmr-simtel20.ARMY.mil
Organization: The Internet
X-Unparsable-Date: Sun, 24 Jan 93 09:15:54 GMT+1

Info-IBMPC Digest           Sun, 24 Jan 93       Volume 93 : Issue  13 

Today's Editor:
         Gregory Hicks - Rota Spain <GHICKS@wsmr-simtel20.Army.Mil>

Today's Topics:
                        "GP" Errors with BC 3.1
                          Case/readln Question
                     FDC (NEC mirco765) programming
                       FDREAD/FDFORMAT revisited
                        Fixed point sqrt anyone?
                 Hard drive problems with Quantum 80AT
                      help needed on AC/DC boards
                        Keyboard Buffer Flushing
                    Looking for 488 data acquisition
       Looking for PD or Commercial Xmodem/ymodem/zmodem package
                       Need a program to play CDs
                          Need help on Win3.1
                            NETBEUI & TCP/IP
                       Norton Commander for OS/2
                     OS/2 Technical Staff Addresses
                          PC/XT upgrade query
                     Serial Communication Question
                    Serious PKZip 2.04 Bug - Beware
                           SYSREQ Key - Why?

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Archives of past issues of the Info-IBMPC Digest are available by FTP
ONLY from WSMR-SIMTEL20.ARMY.MIL in directory PD2:<ARCHIVES.IBMPC>.

----------------------------------------------------------------------

Date: 8 Jan 93 15:11:41 GMT
From: "Brian C. Anderson" <bca@packard.ece.cmu.edu>
Subject: "GP" Errors with BC 3.1

|>  sonix@schunix.uucp (Duane Morin) writes:
|> ... Stuff about GP errors deleted ...
|> >2) Got 3.1.  Can't even install the damn thing.  ZIPs are intermittently 
|> >	corrupted.  Little examination shows that, with cache memory off,
|> >	I have no problem unzipping, with it on, sometimes they get CRC
 
 This is fair proof that your motherboard is not functioning in a happy
way.  486 motherboards are often very sensitive to the 5volt power
supply voltage.  If the 5volt supply is running at the low end of
tolerance, the cache controller chips might not be able to function
quickly enough.
 
 Check to see that you have 5.00volts -0%, +5% on the motherboard's
power connector (red and black leads), when you have all of your
system's cards/disks installed.  If you aren't getting 5.00volts you
should either adjust your supply (HA HA HA, good luck!)  or get a new
supply that does give you 5.00volts.
 
 You wouldn't have this problem if the motherboard suppliers wouldn't
cheat.  What they do is buy all 25MHz 486 motherboards, without CPU or
RAM.  They then plug in the proper speed parts to get either 33MHz or
50MHz.  Well, this would work, except that the motherboard
manufacturer's grade the motherboards for speed.  The ones that fail
50MHz become 33MHz boards, the ones that fail 33MHz become 25MHz...
 
 Now, you ask, "Why does the board work sometimes on my system?"
 
 Well, It's like this, the boards are designed to run at 5v +/- 5%, and
from 0-70 degrees C.  Logic chips such as the cache controller run
their fastest when they are cold and at the high voltage margin, and at
their slowest when they are hot, and at their low voltage margin.  Most
of the time, the power supplies will provide 5.0v on the nose, and you
all will run your machines in comfortable rooms, so you can get away
with using parts that failed to run full speed at 4.75v and 70C.  The
clone builders are banking on this happy coincedence.
 
 Chuck Harris - WA3UQV
 chuck@eng.umd.edu

------------------------------

Date: 9 Jan 93 04:27:42 GMT
From: christopher hall <hallch@cs.colostate.edu>
Subject: Case/readln Question

 stefan@sinus.stgt.sub.org (Stefan Bechtold) writes:
>... text deleted ...
>What I want to do:
>I want to control 15 numbers by a case-statement (so I do have to use
>integer, doesn't I ?), but also want to control all other chars typed in
>(so that the program doesn't exit but prints an error message.)
>
>Do you have any solution ?

Maybe.  I did something similar to this with a file name entry box.
What you might try doing is reading the command in character by
character as you are already doing it.  Then, check the character and
make sure that it is a number.  If it is then append it to a string
which you will later convert to your number.  If it isn't then check if
it is a backspace or a carriage return.  For a backspace you need to
cut the last character off of your storage string (provided there is
one) and redraw the number.  If it is a carriage return then check that
your string is a valid number (by converting it to an integer with the
VAL function.)  Once you know the person has entered a valid number you
can convert it to an integer (although you already did in order to
check it) and VOILA you have your menu selection without a problem.

Let me know if this is what you wanted.  There is room for improvement
but I have given you a general way to do this.  I still remember the
first time that I asked my parents to test a program for me and when
the prompt said "Enter a number please. " my father typed "no".  Of
course it crashed and I had to learn another way to do things.

Regards
Chris Hall

|       |________          Chris Hall
| ||OOO||________>         hallch@handel.colostate.edu
|       |

------------------------------

Date: 8 Jan 93 11:49:46 GMT
From: bwl2324@mzdmza.zdv.uni-mainz.de
Subject: FDC (NEC mirco765) programming

Hello,

I try to program the FDC for sending disk sectors via DMA/channel 2
into memory. This works fine if I read the disk before starting my
routine but if I try to read a disk sector right after booting the FDC
status shows that FDC can't find the Address mark (bit 3 in status byte
0 is set).  I take this step to get the FAT-sector to examine the
diskette's format.  I tried to recalibrate the disk drive but it
doesn't help.  Any considerations ?

	Thanks for helping,
	Steve

------------------------------

Date: Sun, 17 Jan 1993 22:50 EST
From: "John K. Duchowski" <MORRO@drycas.club.cc.cmu.edu>
Subject: FDREAD/FDFORMAT revisited

Hello again Everyone,

Hmm...  in response to my post about FDFORMAT/FDREAD I received several
replies for which I am very grateful.

However, unfortunately for me, the consensus of these replies seems to
be that it is a hardware problem.  I am using a Micronics i486 33 MHz
EISA motherboard with a Phoenix BIOS and OS/2 2.0 with the Service Pack
installed.  Just as some of the replies indicated, both floppy drives
are TEAC, the 5.25" being FD-55GFR and the 3.5" being FD-235HF.  As far
as I can tell, the controller (IDE) is a cheapo, noname, Taiwanese
board.  Having found all this out, I am now thinking of upgrading these
to something more flexible.  Also, while I'm at it, I am thinking of
going all the way to the new 2.88 MB format.  Could anyone suggest
possible alternatives ?  Which controllers, floppy drives, etc. work
best with OS/2 ?  My HD is a 200 MB Maxtor which thus far (knock on
wood) has been working very quietly and reliably.

Before I start dropping major $$$, some sugegstions above included
editing OEM strings in the boot sector.  Could someone please enlighten
me what that does, how to do it and what possible benefits might be
reaped from doing so ?  Many thanks to all of you for your help and
suggestions.

John

------------------------------

Date: 8 Jan 93 13:44:38 GMT
From: Thomas Greve <greve@rs1.thch.uni-bonn.de>
Subject: Fixed point sqrt anyone?

 murrayk@prism.CS.ORST.EDU (the Dodger) writes:
>
>Well? Does anyone know of a quick and dirty way to get a reasonably
>accurate square root of a fixed point integer number? My numbers are
>stored in a 16.16 bit format. I've heard of a few ways, but I'm open
>for ideas. I just want to keep on avoiding floating point for ethical
>reasons. 8^)

I have read a method for integers in a computer magazine some time ago,
and it should work for fixed point numbers, also.

Here we go: You can interpret the 16.16 number as (32bit int)/(2^16),
true? The result can be up to 8.16 accurate, but this depends on the
upper 16 bits of your fixed point number. I'll show you a fast way for
8.8 accuracy and leave the remaining 8 bit as an exercise to the reader
;-)...

The way to go is succesive approximation: root is the (yet to be
calculated) root  8, radicant is the radicant << 16, which is obtained
by simply interpreting the fix as long.

	for (j = 128, root = 0; j || root*root == radicant; j >>= 1)
	  if ((root + j)*(root + j) >= radicant)
	    root += j;
	root <<= 8;	/* now you can cast it back to the fix format */

If you need performance, you can do some bit optimization by
calculating (root + j)^2 iteratively from the last value:

	for (j = 128, jj = 16384, root = 0, rr2 = rr = 0;
			 j || rr = radicant; j >>= 1, jj >>= 2, rr2 >>= 1)
	  if ((rr1 = rr + rr2 + jj) >= radicant)
	    root += j, rr = rr1, /* = root^2 */ rr2 += jj*2 /* = 2*root*j */; 

-- 
				- Thomas

   greve@rs1.thch.uni-bonn.de
   unt145@dbnrhrz1

------------------------------

Date: 19 Jan 93 10:20:00 CST
From: "Baker, Robert E." <BAKERRE@tawc1.eglin.af.mil>
Subject: Hard drive problems with Quantum 80AT

	I have a friend who has a Quantum 80AT (?) drive.  He has over
5 megabytes of bad sectors, and we have a couple of questions:

	1)  Does anyone have the correct drive parameters for this
drive?  We need to make sure we have the CMOS setup correct (heads,
cylinders) before we do something drastic :-), 

	2)  What is considered the 'best' software available to try and
recover some of these bad sectors?  We've tried PCTools DiskFix, and
once it recognizes the drive, it sometimes has problems recognizing the
bad sectors are even there.

	Any help would be appreciated.  Thanks.

	Bob Baker	BAKERRE@TAWC1.EGLIN.AF.MIL
	Troy Hess       HESSTD@TAWC1.EGLIN.AF.MIL

------------------------------

Date: Mon, 18 Jan 93 08:29:50
From: BS04@primea.dundee.ac.uk
Subject: help needed on AC/DC boards

I am trying to hook an Oxygen electrode up to a PC. I understand I need
an AC/DC board to do this. Can anyone recommend a company in the UK
which will be able to help me on this. I have heard of Keigthly (a
yorkshire co.) who are ment to be big in this area.

thanks for your time and help.

Andy Johnston.
University of Dundee,
Dundee
Scotland
DD1 4HN

------------------------------

Date: Mon, 18 Jan 93 03:25 GMT
From: Scott Begin <0005555440@mcimail.com>
Subject: Keyboard Buffer Flushing

Recently, someone asked about flushing the keyboard buffer.  I didn't
see the original question, but having recently worked with this issue,
I noted the sophistication in the answers (such as resetting circular
queue pointers).

I wrote the following program using Turbo Assember (TASMB from
Speedware), although it isn't sophisticated enough to be that much of a
translation to MS Macro Assembler.

;                             KILLBUFF.ASM
;  Author:    Scott A. Begin
;  Date:      12/20/92
;
;  Description:   This program checks the keyboard status to determine if a
;                 key has been pressed.  If so, the keyboard buffer is flushed.
;
;                 This program was written to clear the buffer before using
;                 KEY-FAKE.COM to insert "keystrokes" into  the buffer for
;                 autoexecution of a program from a batch file.

main	proc	near

	mov	ah,0bh	;Check Keyboard Status Function
	int	21h
	cmp	al,0    ;No character available
	je	done	;Exit if no characters in keyboard buffer

	mov	ah,0ch	;Kill keyboard buffer Function
	mov	al,0	;Will not return any characters in buffer
	int	21h
done:
	int	20h	;Terminate
main endp

It should be noted that INT 21h, function 0Ch will clear the keyboard
buffer, and it even allows you to start reading the keyboard after
flushing using INT 21 functions 01h, 06h, 07h, or 08h.

Scott A. Begin       Oak Forest, IL
SBEGIN@mcimail.com

------------------------------

Date: Tue, 19 Jan 93 11:29:42 EST
From: james <PET101@ukcc.uky.edu>
Subject: Looking for 488 data acquisition

I'm trying to hook up an Hitachi digital storage oscilloscope to a 386
PC using a CEC 488 interface.  It works fine, but I was wondering if
there are any freeware or shareware data acquisition programs that can
run the IEEE-488 protocol; in other words, I need a program to retrieve
data from the oscilloscope and save it to some ascii or binary file for
later analysis, using the IEEE-488 protocol....otherwise, I'll have to
write it myself, and in that case, any recommendations on
free/shareware C compilers would be helpful.

Thanks,
Jamer.

------------------------------

Date: 9 Jan 93 15:13:44 GMT
From: Johannes Beekhuizen <johannes.beekhuizen@contrast.wlink.nl>
Subject: Looking for PD or Commercial Xmodem/ymodem/zmodem package

Hello Russell,

On Friday January 08 1993, Russell Trotter wrote to (crosspost 1) All:

 RT> We are looking for Xmodem/Ymodem/Zmodem protocol package for Sun Unix
 RT> workstations, IBM PC's and, Macintosh's.  Anybody know of
 RT> them in existence.  It doesn't have to be specific to each platform,

There is a version of Omen's RZSZ for Unix. I think I saw it on
Simtel20, but I'm not certain. It runs on the Sun without modifications
(option in the makefile provided).

Regards,

           Hans.

fidonet  2:281/527.5
yan-net  123:3183/101
e-mail   johannes.beekhuizen@contrast.wlink.nl

------------------------------

Date: Mon, 18 Jan 1993 23:12 CST
From: From EMCS <EMCS@royal.crc.uno.edu>
Subject: Need a program to play CDs

I recently installed a NEC CD-ROM machine onto a 486 for a friend. It
works fine for reading data and such, however I would like to be able
to give him a program that could be used to play music CD's as well. I
would prefer a Windows application (he's running 3.1). Also installed
is a ProAudio Spectrum sound card in case that makes a difference.

I figured that the software that came with the sound card might include
what we wanted, but it did not.

All replies to the above problem welcome.

  +ed murphy|grad student|university of new orleans|dept. of computer science+
  +                internet: emcs@uno.edu, emurphy@cs.uno.edu                +
  +                "Ed? Well, he's just this guy, you know?"                 +

------------------------------

Date: Sun, 17 Jan 93 10:41:01 EET
From: bermn@bimacs.cs.biu.ac.il (Moby Dick)
Subject: Need help on Win3.1

 Does anybody knows the SVGA Realtek card? How to install it's Win3.0
driver in Win3.1 correctly? Are there some ways to get a driver for
Win3.1 or replace it with another existing driver?

Thanx.
Moby Dick.
_________
| ISoft |
---------

------------------------------

Date: Mon, 18 Jan 1993 13:19 EST
From: Will Polik <POLIK@hope.cit.hope.edu>
Subject: NETBEUI & TCP/IP

To support multiple network protocols simultaneously, you will want
your protocol drivers to be NDIS compatible.  NDIS can handle up to
four different protocols simultaneously.  An inexpensive way to obtain
NETBEUI and IPX is to purchase Windows for Workgroups 3.1, which
includes both of these.

The purpose in WFW is so that you can communicate in a workgroup using
NETBEUI (which is LAN Manager's protocol) and connect to a Novell
fileserver using IPX (the NDIS version of which is called MSIPX).

Appendix E of the WFW Resource Kit describes how to install a TCP/IP
protocol driver, as well.  KEA systems, 604/431-0818, sells NDIS
compatible TCP/IP software, as do other vendors.  A Microsoft technical
support staff member told me that Microsoft will be releasing a TCP/IP
add-on in the first quarter of 1993.

Will Polik
polik@hope.cit.hope.edu

------------------------------

Date: 9 Jan 93 21:03:29 GMT
From: "Timothy F. Sipples" <sip1@ellis.uchicago.edu>
Subject: Norton Commander for OS/2

 mhuth@hardy.u.washington.edu (Mark Huth) writes:
>>There's a new one out now called mrfilepm.zip.  It should be available
>>within a few days at ftp-os2.nmsu.edu (check directory
>>/pub/uploads/sharebbs first).  It is IBM employee written software.

>Tim, do you or does anyone else know if there is a Norton NCD-like
>program available for os/2?  Basically, all it does is allow one to
>change directories from the command line by typing only part of a
>directory name.  For example, to change into /tim/sipples/faq...I could
>just type ncd faq.

At least a couple.  I seem to recall VCD, RCD, etc.  Check the file
/pub/os2/00Index on ftp-os2.nmsu.edu via anonymous ftp.  Search through
until you find one you like.

Timothy F. Sipples      | Read the OS/2 FAQ List 2.0i, available from
sip1@ellis.uchicago.edu | 128.123.35.151, anonymous ftp, in /pub/os2/all/info
Dept. of Econ., Univ.   | /faq, or from LISTSERV@BLEKUL11.BITNET (send "HELP")
of Chicago, 60637       | [Read the List, THEN post to ONE OS/2 newsgroup.]

------------------------------

Date: 8 Jan 93 07:17:44 GMT
From: Mark Kovarski <kovarski@zooid.guild.org>
Subject: OS/2 Technical Staff Addresses

Many thanks go to David for posting this list. Due to the many requests
from users about OS/2 Technical staff member addresses, I will post it
to the various OS/2 Internet conferences.

[Note: David provided numerous addresses that had *no* area of
expertise.  I have deleted these from his list.  I also sorted his
provided list into alphabetical order by area of expertise.  gph]

------------------------------ Cut Here --------------------------------
  To: ALL                           Refer#: NONE                        
From: DAVID MATOCHA                   Read: (N/A)                       
Subj: COMPUSERV IBMER'S     1/2     Status: PUBLIC MESSAGE              
Conf: OS2 (185)                  Read Type: TEXT SCAN (+)               

OS/2 2.0 Technical Support FAQ 11/6/92                                  

OK EVERYONE. Here is a list of OS/2 support persons avaible to help you
on CompuServe.

Anyone on the Internet or BITNET can send mail to persons with
CompuServe accounts. For example, to send Jim Akers mail, who has an
CompuServe ID of 72410,1360, you would send to the following:

72410.1360@compuserve.com

Note the comma in the UserID is replaced with a period. Also note that
those individual listed without an area of expertist should not be
contacted yet. I will keep this list up to date. It is available from
CIS. I will also upload it to hobbes and watson.

   ---Ken
kbass@gmuvax2.gmu.edu

User ID    Name                Area of Expertise
71075,3143 MICHAEL DUNN        CID ENABLEMENT
71075,3150 LEN LESLIE          CID ENABLEMENT(OS2DF2)
71075,2431 ROGER LEWIS         CID ENABLEMENT(OS2DF2)
71075,2426 PETER F HAGGAR      CONTAINER CONTROL SHIPPED WITH OS/2 2.0, PMAPI'S
72370,136  STEVE M MILLER      CUA / USER INTERFACE
72370,140  BINH NGUYEN         CUA / USER INTERFACE
72370,141  BILL ALLEN          CUA CONTROLS LIBRARY/2
72400,2754 JUDITH W OSBORNE    DAP
71075,3323 DAMIEN SCOTT        DAP PDK CD ROM (OS2DF2)
71075,3157 RICK EFRUSS         Device Drivers
72360,3611 DAN K LEE           DFI, BASE OS2 API, PM API
71075,2762 ROB SEMONIS         DMK, AND TOOLKIT
72370,1201 TONY INGENOSO       DOS APP COMPATIBILITY, AND SYSTEM CONFIGURATION.
72360,3555 DOUG AZZARITO       DOS EMULATION + COMMUNICATIONS
72370,274  BOB EASTON          ES/LS, COMM MGR, DB MGR, TCP/IP, CID, AND OS2USE
71075,3324 JOHN MCCLELLAN      ESDTOOLS FOR DAP
72400,2740 STEVE WOODWARD      GENERAL OS/2(VIDEO DRIVERS +WPS)
71075,2430 SAM DETWEILER       GOLLY,OS/2 INSTALL,PDK,CDROM,C,ES, CM, CID,PROGRA
72360,3554 KELVIN R LAWRENCE   GRAPHIC ENGINE,GPI,PMWIN,VIDEO
72370,562  MIKE GERENTINE      INSTALL/2, TEXT CONTROL, DIST. APPL, CAU CONTROL
71072,3171 ART BORREGO         LAN
71075,2611 BOB GIDEON          LAN 3.0 SERVER AND NOVELL INTEROPERABILIT
71075,1445 DON HAILE           LAN HARDWARE, OS/2 COMM MANAGER
72410,1360 JIM AKERS           LAN SERVER AND COMM MANAGER, ISV QUESTIONS
72370,1117 RANDALL JAMESON     LAN SERVER, NTS/2
71075,2551 SAM P CASTO         Manager, Boca Technical Support Group
71075,1107 LARRY DAVIS         MEDIA RELATIONS TECHNICAL SUPPORT, AND MONITOR C
71072,562  LAURIE TURNER       NTS/2 SUPPORT
71075,340  JOHN GOLDTHORP      OS/2 APP. DEVELOP. SUPPORT
71075,2106 MICHAEL PERKS       OS/2 PRINT, NETWORK AND COMMS PRINT
71075,2553 JOE POLIZZI         OS/2 SHAREWARE, PDK,TOOLS GROUP(DAP)
72370,135  E GENE BARLOW       OS/2 USER AND PC USER GROUPS
71075,1111 LARRY SWOFFORD      OS2DEV AND IBMOS2 FORUMS
71075,2427 DAVID A KERR        OS2DF1 PM API'S
72360,3474 ROSS L COOK         OS2DF1, OSDF2, OS2USER, OS2SUPPO, DDJFORUM, WINN
71075,1117 JOHN D WEBB         OS2DF1-PM API'S,OBJECT TECH, DEBUG
71075,1337 IVAN BIDDLES        OS2DF1-PM WINDOW MANAGER, AND CONVERTING TO CSET
71075,524  KAMRAM REJAEE       OS2DF1-SYSOP THUNKING AND DEVICE DRIVERS 
71075,3152 MIDGE PORTNEY       OS2DF2 CD ROM PDK
72360,3645 DON R HEDDING       OS2DF2 COMM MAN,OS2SUPPORT, NOVELL NETWIR
72370,1116 WF DAYTON           PC COMPANY CUSTOMER SATISFACTION
71075,3153 MARK LUTZE          PDK SUPPORT
71075,3564 JOHN MOTE           PL/1 COMPILER DEVELOPMENT
71075,3566 BOB THIMSEN         PL/1 PACKAGE/2
72370,147  ALAN WARREN         PmDRAW, PM and GPI programming
71075,133  RODNEY MAXWELL      PMX
71075,206  MATHEW F RUTKOWSKI  Printers
72360,3621 JOSEPH J CARUSILLO  SOFTWARE DEV.SUPPORT+SERVICE
72400,2746 RON BOYAJIAN        SYSOP SECTION 14 OS2DF2
71075,134  LEE COLE            TCPIP
71075,135  BRYAN FREY          TCPIP
71072,1534 PAUL BRIGHTLY       TOOLKIT
72410,624  ERIC NELSON         TOOLKIT, TECHNICAL LIBRARY, AND TECHNICAL DOCUME
72360,3615 MIKE WORRALL        WIN-OS/2, WINDOWS APPLICATIONS UNDER OS/2
72370,1265 JOE HLAVATY         WIN/OS2
71075,1754 SHEILA MCDONALD     WIN31/32 bit GRE Beta
71075,3454 DARREN MICLETTE     WINOS2
71075,3160 GUPTA RAJIV         WINOS2 SUPPORT
72370,512  LORI DAY            WORDPERFECT RELATED ITEMS
72370,137  ROD SMITH           WORKPLACE SHELL, APPLICATION DEVELOPMENT TOOLS 

Here are some last minute additions
Direct Internet Connections:

C Set/2                       cset2@vnet.ibm.com
WorkFrame/2                   workframe@vnet.ibm.com.

If you know any other OS/2 related Direct Internet addresses, send me
an E-Mail message and I will include it.

Mark K.
E-Mail: kovarski@zooid.guild.org

------------------------------

Date: Sat, 16 Jan 93 14:56:04 CST
From: ST2975@siucvmb.siu.edu
Subject: PC/XT upgrade query

I recently read about some PC/XT comments in the IBM-DIGEST.  I am
hoping someone might be able to provide some light on upgrading an old
machine - a Bondwell Pro 8 Turbo 8088 Laptop.  I bought this machine
for around $75.

The machine has the following:
DOS 3.21
384 LIM EMS and 640 k in user RAM
No co-processor, though I may purchase one for @ $65.
An 80C88 CPU (High speed, low-power version of the 16 bit 8088
  microprocessor
AND the ability to upgrade to one megabyte of user RAM for data and
  program storage.

My questions concern the ability to upgrade the system memory to 1 Meg.
the machine has four empty 14 pin slots markedas follows:

EPROM 1/ROM 1          EPROM 2/ROM3
EPROM 3/ROM 2          EPROM 4/ROM4

I am not sure of the type of chips to buy.  For example, in "Computer
Shopper" I have identified 3 potential chips: 27C256 at 150ns; and
27256 at 180ns and 200ns respectively.  This stuff is all Greek to me
The chips are really cheap.  I am just not sure what the EPROMS desig-
nations mean or what ns (nanoseconds?) has to do with anything?

I tried the help line for the manufacturer over a period of two weeks.
I did not recieve any replies.  I tried the chip company, but they just
sell chips.

I would greatly appreciate any advice.  I though this machine was a
good buy for $75.  It even has an internal 1200 baud modem.

Michael Parker BITNET:ST2975@siucvmb.bitnet
Southern Illinois University

------------------------------

Date: 8 Jan 93 18:30:45 GMT
From: Marko Kohtala <mkohtala@lesti.hut.fi>
Subject: Serial Communication Question

asu@server2.panther.mot.com (Russell Trotter) writes:

>Hello,
> 
>  A few days ago, my boss posted a question needing some info on
>setting up/initializing the com port and read/write howto's.  After
>digging through the code we got from replies, we found that the best
>way to do this was to use some code that would actually access the
>UART?

Yes. If you do not want to access the UART directly, you can get a
FOSSIL device driver that does it for you and use the FOSSIL. Most BBS
programs use this approach.

Two popular FOSSIL device drivers are X00 and BNU. They come with all
the necessary API documentation.

>My question is, what, precisely, are these status interrupts for, and
>are they absoultely necessary?

Receiver Line Status
	Source: Overrun, Parity or Framing error or Break
	Reset: Read the LS register

Modem Status
	Source: Clear to Send or Data Set Ready or Ring Indicator or Data
		Carrier Detect. 
	Reset: Read the MS register

They are not absolutely necessary. Modem Status can be used to
implement hardware flow control: change in Clear to Send causes an
interrupt and if it is set, the interrupt routine should start to
transmit if there is data in the transmit buffer.

Also, for these to work, you must make sure that the interrupt
conditions are reset. The thing to do to reset is shown above. If you
do not reset the interrupt, it will stay on and there will not be
another interrupt on AT bus. In MCA I think it will cause the interrupt
handler to be called constantly untill the interrupt is reset thus
hanging the machine.

Received Data interrupt can be reset by reading the Receive Buffer
register. Transmitter Holding Register Empty interrupt can be cleared
by reading IIR or writing to THR.

If you have any problems, I am willing to write you a tailored comm's
module for a reasonable compensation. I have written the one used in
Telemate communications program.

Marko Kohtala - INTERNET:Marko.Kohtala@hut.fi, mkohtala@otax.tky.hut.fi
Student at (not representative of) the Helsinki University of Technology

------------------------------

Date: 8 Jan 93 22:09:31 GMT
From: "Ranseus (Jim Knepley" <knepley@cs.colostate.edu>
Subject: Serious PKZip 2.04 Bug - Beware

rdippold@cancun.qualcomm.com (Ron Dippold) writes:
>Another bug has shown up in PKZ204C (I can't believe how buggy this
>is), confirmed by several people (including on CompuServe) and tried
>by me.  If you backup your hard disk with the "-&" option you may lose
>some of your data.

It is my experience that PKUNZIP will notify you that the file didn't
inflate correctly but the file is fine.  Your mileage may vary.

If ANY file spans 2 disks, it'll report a CRC error for the file that's
being completed.  I restored 4 disks today and got a message every time
I put in a new disk, but the files were fine.

Jim
----- knepley@cs.colostate.edu --------------- Boycott Colorado -------------
 Jim "Ranseus" Knepley |  Avoid rectal-cranial inversion. 
 Programmer, magician, |  "Gun's don't kill, it's those bullet things"   
 computer geek.        |  

------------------------------

Date: Sat, 16 Jan 93 12:28:43 EST
From: "B. Trieselmann" <UGG00031@vm.uoguelph.ca>
Subject: SYSREQ Key - Why?

OK, why does my keyboard have a SysReq key? Is there ANY use for
this???  Thanks for a patient reply!!! Bruce.

------------------------------

End of Info-IBMPC Digest V93 #13
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