Newsgroups: comp.robotics
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From: rstevew@armory.com (Richard Steven Walz)
Subject: Re: C and the printer port?
Organization: The Armory
Date: Sat, 23 Jul 1994 12:14:39 GMT
Message-ID: <CtE7CK.JJF@armory.com>
References: <774792519snz@labman.demon.co.uk>
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In article <774792519snz@labman.demon.co.uk>,
ANDREW WHITWELL <ANDREW@labman.demon.co.uk> wrote:
>
>
>If you want to control stepper(s) motors from the parallel port then I can
>tell you now that it is very easy - we have built an 'interface' card
>that goes between the port and the stepper motors and has 16 outputs and 
>16 inputs (soon to be 64 of each !).
>
>The question of running the motors at a useful speed (usually fast) seems
>to make everyone start diving into C and assembly language - WHY ?
>
>The software for our stepper controller was written in POWERBASIC 3.0 and
>whilst being very easy to write (you can't get much simpler than BASIC) 
>it was also very fast. After converting the same code into C and PASCAL
>there was no massive difference in speed - even on a slowish 286 running
>four stepper motors we had to slow the program down - not try to get it to
>go faster !. The average fast running speed is about 4000 steps/second !
>
>Some people may think this is a load of rubbish or think that I am talking
>a load of rubbish and if this is the case then can anyone show me a routine
>written in C or assembly language that is EASY to use and understand. I am
>no software engineer but using C or assembly language to try and develop
>software for the first time (especially for a beginner) is very time
>consuming.
>
>The card we use now has not been used to it's full potential, at the moment
>we are using it to control a 4-axis robot - it's other uses are wide and
>varied when it comes to using stepper motors to move things about.
>-- 
>MARK
>LABMAN AUTOMATION LTD.
--------------------------------
I have to agree. I have been taught formal C before, and while getting a
very good grade in the course, it is my most hated language next to COBOL!
They just used all the remaining obscure characters left over so they
didn't "look like" PASCAL!!! And those are the least descriptive characters
for eye recognition! I might like it if it were redesigned with a more
sensible character set. But I program in QuickBASIC all the time. And I
have cross translated C programs and run QuickC by Microsoft against Quick-
BASIC, and the difference in execution time or compile time was trivial,
about 3.5% if that. And the code size is about the same triviality, if not
more. I write in assembler for really fast things, and use the routines
inside QuickBASIC!
-Steve Walz   rstevew@armory.com

