Re: G-code interpreter/stepper controller

Hi,ok, but why the difference between the limit switch and the securityswitch ? if the limit switch is hit at one end of the axis, isn'tthat the same basically as hitting the security switch on the otherend ? Or is the limit switch actually used to reset the machineinitially only ?--- In CAD_CAM_EDM_DRO@y..., "Luc Vercruysse" <luc.vercruysse@p...>wrote:> On most CNC machines there are 2 switches on each side of the axis.One is a> limitswitch , the other one is a security switch.> The limitswitch can be handled within software. Once a switch ishit, > > very good specs. Is the system based on some microcontroller ? Istheyes, atmel avr at90s8535> interpreter running on the host computer ?no, on the microcontroller> Is software based on EMC ?no, completely written from scratch. EMC is much more sophisticated.My interpreter is quite limited, it only supports a very minimal setof G-codes, sufficient however to remove any hard real-timerequirements on the host. With this and a dallas semiconductors TINI,you could have a simple CNC or router, or multi-axis robotmanipulator on an ethernet network for a very low cost.brunobruno> Luc> > > > ----- Original Message -----> From: "bschwand" <bschwand@y...>> To: <CAD_CAM_EDM_DRO@y...>> Sent: Tuesday, November 05, 2002 8:30 PM> Subject: [CAD_CAM_EDM_DRO] G-code interpreter/stepper controller> > > > Hi everybody,> >> > I am in the finishing/debugging stages of a 3 axis steppercontroller/> > G-Code interpreter.> >> > The missing part is how to handle endswitches.> >> > My assumption is that hitting an endswitch is a catastrophicfailure,> > and it should never happen; therefore I was going to have the> > controller freeze all movements, signal the error (a big red LED)and> > let the operator shutdown the system, manually back off the tools,> > etc. and restart.> >> > I think that trying to have the tool be "smart" and back off thetool> > itself, etc. could possibly lead to damaging the machine and orpart> > being machined.> >> > Does this make sense ? What is usually done, or expected in such a> > case ?> >> > Please let me know what you think is the best way to handle> > endswitches, and if you have experience with other systems or> > software, let me know how it is done.> >> > BTW, this system has the following features:> >> > - communicates with the host computer through a serial RS232 port> > (the host could be a palm pilot :-) ), use of hardware (RTS/CTS)> > flow control to ensure dataflow integrity.> > - embedded basic G-Code interpreter that supports linear and> > circular interpolation in all axis> > - extensible to up to 8 axis (through an extension board, to be> > designed)> > - automatically goes to low-current (holding) setting for a givenaxis> > if that axis has not been active for 100 milliseconds> > - active current control through integrated chipset, thus verylittle> > wasted power. Running and holding current are configurablethrough> > separate potentiometer, up to 3 amp per axis (although I havenot> > tested this much power lacking the needed power supply...)> > - each axis can be configured as to what the positive or negative> > direction is (to accomodate for different machine configuration)> > - configurable "rapid transverse speed" (G00 code)> > - configuration settings are saved in permanent memory (eeprom) so> > they remain between shutdown/reset.> > - up to 10'000 steps per seconds (is this overkill ? my steppersstall> > after 900 steps/sec...)> >> > Currently supports unipolar steppers, in full-stepping mode. Abipolar> > stepper power board will come next.> >> > All feedback much appreciated, thank you.> >> > bruno> >> >> > Addresses:> > FAQ: http://www.ktmarketing.com/faq.html> > FILES: http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/files/> > Post Messages: CAD_CAM_EDM_DRO@y...> >> > Subscribe: CAD_CAM_EDM_DRO-subscribe@y...> > Unsubscribe: CAD_CAM_EDM_DRO-unsubscribe@y...> > List owner: CAD_CAM_EDM_DRO-owner@y..., wanliker@a...> > Moderator: jmelson@a... timg@k... [Moderator]> > URL to this group: http://groups.yahoo.com/group/CAD_CAM_EDM_DRO> >> > 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 toreach it if> you have trouble.> > http://www.metalworking.com/news_servers.html> >> > http://groups.yahoo.com/group/jobshophomeshop I consider thisto be a> sister site to the CCED group, as many of the same members arethere, for OT> subjects, that are not allowed on the CCED list.> >> > NOTICE: ALL POSTINGS TO THIS GROUP BECOME PUBLIC DOMAIN BYPOSTING THEM.> DON'T POST IF YOU CAN NOT ACCEPT THIS.....NO EXCEPTIONS........> > bill> > List Mom> > List Owner> >> >> >> > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/> >> >> >