Using PowerBasic DOS for ROM DOS 6.22

[Jim Ran Smith]

I just ordered PowerBasic DOS in order to work with programs
for a handheld barcode device that has ROM-DOS 6.22.

Does anyone have any experience that would help me?
I have a manual that tells me differences in the dos commands
from normal DOS but nothing to help me with possible problems
with the basic code. The programs were orginally written with
QuickBasic but QuickBassic seems to create all sorts of
problems with my XP development machine.

[Donald Darden]

QuickBasic Programs will need to be largely rewritten in order to
be able to compile them with any form of PowerBasic. The PB/DOS
comes closest in syntax to matching QuickBasic, but requires that
you run them in DOS emulation. Depending upon various factors,
such as the SCREEN mode you are using, the use of COMM ports, any
attempts to read/write directly to Screen Buffer, the use of the
DRAW command, efforts to stuff the keyboard buffer, the use of
EMS or XMS, or the fact that large QuickBasic programs had to be
written as a series of modules (which is totally unnecessary and
unsupported in PowerBasic), means that many of the conversions are
reasonably straightforward (and can be automated with a program
for that purpose), but others may mean a significant restructuring
of the source code.

Many peole advise you just to rewrite your programs from scratch,
but that is not always necessary or desireable. Still, if you
have large or numerous QuickBasic programs to contend with, you
may have a sizeable task before you.

Over the last three years or so, several commercial entities have
sought PowerBasic programmers who can convert QuickBasic (or PDS)
programs into PB/CC. As I said, PB/DOS is closer to Q@uickBasic,
but the desire is to convert to a form that is better suited to
Windows, and that is likely to be PB/CC. Although there are
some that favor the idea of converting to PB/Win instead, as it
opens additional possibilities in terms of creating DLLs, and in
the addition of event-driven processes.

It might help you to research this topic on these forums and
see what further comments have been made. I think you will find
this general concensus:

    1.  It can be done, but some question the wisdom/effort involved
    2.  Most companies that want this done, seriously underestimate
        what it take, the cost, and the time to get the job done.
    3.  There are many people willing to attempt it, if the price is
        right or the work looks like it might last a good while.
    4.  Not everyone has had the necessary experience to quantify or
        measure the scope of the job, so may underestimate the sheer
        scope of the task by several orders.
    5.  If expectations are not realistic, the price will be off, 
        and the time too short, resulting in an unsatisfactory and
        unfavorable conclusion.

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Old Navy Chief, Systems Engineer, Systems Analyst, now semi-retired

[Donald Darden]

Rereading your original post, you should be able to use PB/DOS
with DOS 6.22 with no problems. However, trying to use a
Windows XP machine for your development is going to cause you a
number of difficulties. I recommend that you consider an
alternate operating environment for your development as well.
You could use a cheap old PC that just has DOS or an earlier form
of Windows. or attempt to use PB/DOS under a Linux with the
machine that you have.

Saying you have DOS 6.22 in ROM is not really a clue as to the
specifics of the hardware or the I/O capabilities of the
handheld barcode reader. Fact is, I can't figure out if the
reader uses DOS-type commands internally, can store its own
program, or you are in possession of a hand-held device that
comes with an instruction book/examples to explain how to access
it using DOS commands (and assumes you are running DOS 6.22).

Does it connect to the serial/parallel/USB/Game port to your PC?
Some clarification seems to be in order. Otherwise, I have no
idea of what limitations you may encounter.

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Old Navy Chief, Systems Engineer, Systems Analyst, now semi-retired

[This message has been edited by Donald Darden (edited October 13, 2005).]

[Bob Zale]

Jim--

While PB/DOS and QB are certainly not clones, I'm afraid Mr. Darden's negative comments are totally unrealistic. Just plain wrong.

PB/DOS does not require "DOS Emulation" (whatever that is, in this context). Screen modes are virtually identical except for one. COM ports are handled virtually identically. Read/Write of the screen buffer is absolutely idnetical. DRAW is identical, etc., etc. I think you get the idea.

Yes, you'll have to make a few changes, but you'll get there, just as thousands of others have done. {smile} PowerBASIC staff will be very pleased to assist wherever necessary! Just ask here or by email to [email protected]

Regards,

Bob Zale
PowerBASIC Inc.

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[David J Walker]

I wouldn't bother trying to develop anything to do with DOS under XP if I were you.
I've tried, at length. As you've already discovered, there are just too many "issues".

I've tried, it's just not worth the hassle, especially if the product isn't going to need to
run under XP anyway.

I now run my DOS development system on a 200MHZ notebook with a full size keyboard and mouse
connected to the network, it's much easier.

Is shouldn't cost you anything other than desk space, I've seen suitable machines in skips
(in fact, I've put them there!)



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[Jim Ran Smith]

Thanks to you and Bob Zale for your comments.
I have some PSC Falcon 320 data terminals.
The programs that are QuickBasic are using simple disk
files and displaying to the screen using Locate, print, etc.
Very straight forward. The files are downloaded using standard
communications programs after data input.

After downloading the PB-DOS I have
found only 1 compile problem so far
that was easily fixed. I have noticed some
problems with the XP running slow and I may try to
use a Windows ME PC to do the development.
The debug seemed to lock up twice.

One of the reasons to go to PD-DOS is to make it easier
to enhance the programs in several ways which from
your comments will be better to do on PB.



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[Criss French]

I have been writing survey data collection software in PB/DOS
for several years now. When I started the job I was working
in M$ QB, and had a horrible time with quirky behavior, so
I finally switched to PB and all of the nightmares went away.

I run on Husky FC486's with DOS in rom, and have no problems.
It is not however ROM-DOS (no experence with that).

I bet that as long as your code avoids strange interrupt calls,
and seeing as how it uses simple screen access, you should have
really no problems.

I don't really recommend XP as a programming space. I have tried
Win 2K, but but had (supposedly solvable) common problems with
getting EMS to work. Too lazy to fix, but this forum has seen MANY
excellent threads on making it work. Still, it's an emulated DOS
environment with a shaky track record. Good luck.

My preffered dev environment is WIN98se, using Editpad Pro to edit
code, and then compiling from the command line. Since PB lets you
put all the compile options in the source, it's really quick and easy.
I have no problems with compatability, although if you wanted to
use HUGE arrays you would need to make sure that you have EMS
working. That can be tricky, depending on how your modern machine
chops up the first 1MB with roms. My 2800+ desktop still reliably
and accurately does the DOS thing from inside windows. Same story
on my old 266Mhz laptop, plus it is handy in the field.

I have used PB's IDE a few times for really difficult debugging,
but I find it akward from a Win user's perspective (wierd keys...)
I usually only use it for straight trace functionality when pressed,
and find it easier to just do edit-compile-run cycles, with
error trapping if thing is actually crashing rather than
just mis-behaving. If you have doskey running in your dos box,
you can usually just hit cursor up a couple times to re-compile,
then again to run.

Conversion tips:
-pay attention to the greatly improved COM port open flags. I
usually set it to ignore all errors. Handy.
-watch out for COMMON, SHARED, SUB stuff, it is different in PB
-when you run a program in a 'dos box' make sure you go full
screen BEFORE your program goes into any graphics modes for
best results.
-the best thing is all the stuff you can improve on over QB,
given the better commands and syntax.



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What can go wrong will go wrong.
Anything can go wrong.
What hasn't?!?!

[Davide Vecchi]

if you wanted to use HUGE arrays you would need to make sure that you have EMS working.

IIRC it's only VIRTUAL arrays which need EMS.

My story about going from QB to PB is very similar to Criss's one, right in the automated data collection field (barcode), even though it's about sw running on DOS-only PCs connected through serial ports to barcode printers and scanners. I absolutely second Criss's suggestions regarding the transition, especially the last one.

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Davide Vecchi
[email protected]

[Jim Ran Smith]

Originally posted by Davide Vecchi:

if you wanted to use HUGE arrays you would need to make sure that you have EMS working.

IIRC it's only VIRTUAL arrays which need EMS.

My story about going from QB to PB is very similar to Criss's one, right in the automated data collection field (barcode), even though it's about sw running on DOS-only PCs connected through serial ports to barcode printers and scanners. I absolutely second Criss's suggestions regarding the transition, especially the last one.

My Thanks to Davide and also Chris.
I printed your comments out and put in front of PD Dos Manual
for review as I proceed. I have now used IDE and found my error
fairly easlily. I have switched to a Windows ME for development
and it works fine so far. I ran the program QB2PB sample program
and it appears to be a little out of date. I guess I should look
at that program to see about other possible problems.


Again thanks too everyone for your comments. I am sure they will continue to be helpful.

Jim Ran Smith


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