RE: [CAD_CAM_EDM_DRO] Re: Was Chopper circuit - Now ver 3.2, G298

Hi Tony,

just a quick question. Do you isolate the Pic from the printer port with
opto-isolators?

As a general question. Is it really necessary to isolate the printer port
from the control circuitry of a stepper driver?

Thanks,

Peter Homann
<mailto:peter.homann@...>
Work : +61 3 8530-7755
Adacel Technologies Ltd Fax : +61 3 9596-2960
250 Bay St, Brighton 3186, VIC, AUSTRALIA Mobile : 0421 601665
http://www.adacel.com.au Australian Software Engineering Excellence


-----Original Message-----
From: Tony Jeffree [mailto:tony@...]
Sent: Wednesday, 10 April 2002 10:44 AM
To: CAD_CAM_EDM_DRO@yahoogroups.com
Subject: [CAD_CAM_EDM_DRO] Re: Was Chopper circuit - Now ver 3.2, G298


At 23:14 09/04/2002 +0000, you wrote:

>Just thinking; I recall someone on the list that has already replaced
>the 'L297 with a PIC. And the PIC could be the heart of a single axis
>"jogger", for a 4th axis rotary table, for example. Kinda like
>Sherline's controller? (Bill's ears perk up). I don't know if it's any
>cheaper, but some things like limit and E-stop switches could be built
>in. Same for PAL (or eqv).

Done that...I have an initial production run of single-axis
PIC/L297/L298-based rotary table controllers in progress right now...am
working on the documentation as we speak. Headline specs:

-Will handle any drive ratio between 1:1 and 99:1 - software settable
-Software settable motor current up to 2A/phase
-Idle current can be set as up to 50% of the motor current
-Supply voltage up to 40V
-Jogs in increments of +- 1/100th, 1/10th, 1 or 10 degrees
-Division mode handles all divisions from 1 to 999
-Degrees mode handles any angular move in range 0.001 to 360.000 degrees
-All moves calculated to the nearest 1/2 step - errors are evenly
distributed to avoid cumulative errors creating the "thick or thin tooth"
problem. Display shows desired position and actual angular position
-Can be driven via external step-and-direction signals to use as a "true"
4th axis
-Can be used to drive an external power stage via step-and-direction
signals to allow higher power motors to be used
-Controlled/configured via a 16-key keyboard & a 2-line by 16-char LCD
display.

Pics & fuller specs to follow...

Regards,
Tony




Addresses:
FAQ: http://www.ktmarketing.com/faq.html
FILES: http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/files/

OFF Topic POSTS: General Machining
If you wish to post on unlimited OT subjects goto:
aol://5863:126/rec.crafts.metalworking or go thru Google.com to reach it if
you have trouble.
http://www.metalworking.com/news_servers.html

http://groups.yahoo.com/group/jobshophomeshop I consider this as a sister
site to the CCED group, as many of the same memembers are there, for OT
subjects, that are not allowed on the CCED list.



Post messages: CAD_CAM_EDM_DRO@yahoogroups.com
Subscribe: CAD_CAM_EDM_DRO-subscribe@yahoogroups.com
Unsubscribe: CAD_CAM_EDM_DRO-unsubscribe@yahoogroups.com
List owner: CAD_CAM_EDM_DRO-owner@yahoogroups.com, wanliker@...
Moderator: jmelson@... timg@... [Moderator]
URL to this page: http://groups.yahoo.com/group/CAD_CAM_EDM_DRO
bill,
List Mom
List Owner



Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/