parallel port driver

Jiri Baum: > As I wrote above, at least one such system is available - in-computer board > (8255-based), connected via ribbon cable to a break-out board, which has > pluggable modules (input, output, solid-state, relay, 240V etc). Petr Baum: # supplied by Advantech: # PCL-722 emulates 8255 (a few of them?) # PCLD-7216 I/O module carrier Jiri -- Jiri Baum <[email protected]> Q: Why did the chicken cross the Moebius Strip? A: To get to the other... um... er... --r.h.f.r _______________________________________________ LinuxPLC mailing list [email protected] http://linuxplc.org/mailman/listinfo/linuxplc
 
C

Curt Wuollet

Hi Pitr and all There are kits for the parallel port already. And yes, there are solutions like the OPTO racks that work with 8255 type cards already and let you plug in modules. Said modules are awful spendy. Perhaps fine for commercial projects but discouraging for us poor folks. The reason I'm considering doing this is I think it can be done closer to 1 USD per port than 10 or more. By using dense packages we can get a lot more ports per buck. And yes Willy, I'll post a pinlist for the DIO48 I've got They are regular .1" double header connectors that work with IDC's for ribbon cable If you want to do this in eagle and it produces the Gerber files most proto fabs want, go for it. I was gonna use this as a vehicle to try out PCB, a free PCB layout tool that I'd tried before but which didn't do Gerber lightwriter files until recently. I'd been doing boards with a free DOS package under dosemu. (Yes, I know, but time was short) There was a hook with Eagle somewhere, I think you had to get a fax to Germany or something and I never suceeded. I also know of a fab that's got unfilled capacity and may offer good pricing. It's AP circuits of Alberta Canada. But, again, are automation types ready for pins that can be either? I've never seen that on automation gear. And opto isolators are almost a requirement for stuff that goes from machine to machine. Why don't we pool our research? Regards cww _______________________________________________ LinuxPLC mailing list [email protected] http://linuxplc.org/mailman/listinfo/linuxplc
 
>There are kits for the parallel port already. And yes, there are >solutions like the OPTO racks that work with 8255 type cards >already and let you plug in modules. Said modules are awful >spendy. Perhaps fine for commercial projects but discouraging >for us poor folks. The reason I'm considering doing this is I >think it can be done closer to 1 USD per port than 10 or more. >By using dense packages we can get a lot more ports per buck. IMHO commercial projects are unlikely to go for combination of [ desktop PC + Puffin + LPT ], so we can safely ignore their needs as far as this little exercise is concerned. Who may be interested / tempted - - Linux fans who want to try everything Linuxish - students/kids who want to play with control (X-mas tree blinking Morse code etc) - hobbyists (model trains, automatic feeding of pet lizards, pigeon return time logging etc.) - semi-professionals: farmers etc., who can never justify cost of "real" automation but who may need simple control sequences for their particular trade. All these people need system, which is cheap, does not require much learning, is reasonably reliable and easy to get. (The last group - semi-professionals - may go for more costly solution, if they found cheap solution useful but failing on reliability. So it is nice to have hardware upgrade - module racks - path for them.) >And opto isolators >are almost a requirement for stuff that goes from machine >to machine. Why don't we pool our research? I am sure that all approaches so far suggested have some merits and will be useful, if they are developed and available. We are also almost at stage where "Puffin Users Group" web site, collecting successful hardware designs and projects is needed. Cheers Petr _______________________________________________ LinuxPLC mailing list [email protected] http://linuxplc.org/mailman/listinfo/linuxplc
 
C

Curt Wuollet

I quite agree on the printer port attachment, although the EMC project does use this. For the IO cards, I want to produce "real" industrial IO that companies can be comfortable with for "real" applications. This would mean that as soon as code is ready people can do industrial control with it. They can do this with Ethernet and modbus/tcp IO from an existing automation company now, I believe (correct me if I'm wrong :^) ) But to get pilot projects going, I think we need a clear, easy, inexpensive way to do "real" work or directly replace what IA folks are using now. It would be even better if this could be a single package, ie, an 8255 type card with industrial type I/O built in. And that is not out of the question as there isn't much on one of these cards, but for right now, an inexpensive add-on that "industrializes" the inexpensive TTL IO cards seems like a good approach to have something solid soon. I hate the answer I have to give when people ask "What can I do with it" I think it's also important that they don't have to change what they are doing out past the terminal strip. Regards cww _______________________________________________ LinuxPLC mailing list [email protected] http://linuxplc.org/mailman/listinfo/linuxplc
 
J

Johan Bengtsson

&lt;huge clip> >kits or at least boards available. For that matter, if my day job company were >to offer kits, >would that be a conflict of interest? Perhaps, but I don't think so. This would not be the only I/O solution anyway. /Johan Bengtsson ---------------------------------------- P&L, Innovation in training Box 252, S-281 23 H{ssleholm SWEDEN Tel: +46 451 49 460, Fax: +46 451 89 833 E-mail: [email protected] Internet: http://www.pol.se/ ---------------------------------------- _______________________________________________ LinuxPLC mailing list [email protected] http://linuxplc.org/mailman/listinfo/linuxplc
 
I think there's only a conflict of interest if you steered the design work toward your own proprietary designs or existing products that are unique. This is meant to be OPEN, after all. If a certain I/O paradigm fits best, let any board manufacturer make kits if they can make a dime on it, as long as there is nothing to prevent other manufacturers from making compatible kits! It almost makes me wonder if there is a schematic-level equivalent to a GPL or LGPL (as Curt touched on in his posting). We could create schematic "building blocks" to support the software design that are free for any equipment manufacturer to encorporate into their board or system-level designs. Wouldn't that be a hoot if board manufacturers who add circuitry to our building blocks also had to release their schematics to the cause... Rufus In a message dated 3/7/01 11:00:07 AM Eastern Standard Time, [email protected] writes: << Subj: Re: LinuxPLC: Parallel port driver Date: 3/7/01 11:00:07 AM Eastern Standard Time I'll let someone else deal with the PC parallel port, the variations have always scared me off. <custom design snipped> Since I need this functionality for paying projects, I have considered doing the design and releasing the schematics and artwork to the LPLC project. We could even do kits, but that comes very close to commercialism. <technical considerations snipped> Perhaps someone not directly involved in the project would make kits or at least boards available. For that matter, if my day job company were to offer kits, would that be a conflict of interest? _______________________________________________ LinuxPLC mailing list [email protected] http://linuxplc.org/mailman/listinfo/linuxplc
 
Hi, I would suggest keeping the steps small and simple. First, why not a simple board with optoisolators for 24Vdc inputs, and triacs on outputs for 120Vac outputs that plugs directly into the parallel port - no cables. Just do it with 4 in and 4 out and have connections on a terminal strip. Make the board a small footprint, no wider than the DB-25 connector, and longer than necessary. This board can be used directly with Mario's PPT driver. Things that can be left for later might be; - separate breakout boards - fuses, reverse voltage protection, etc. - different output types - transistors, relays, etc. - shift regiesters for banked IO outputs - soucing/sinking/autoswitching inputs - analog IO - etc. If the board layout is done with Eagle, I will fabricate some boards here (on a PCB mill) and give them to students in a course that starts in two months (May). I would also be willing to run some extra boards for others in the Puffin group. Hugh _______________________________________________ LinuxPLC mailing list [email protected] http://linuxplc.org/mailman/listinfo/linuxplc
 
W
Hi, What about forgetting a parallel port interface and using something like the attached? I think these modules cost about $20 in quantities, we could make a board that accepts one of these and then put eight "generic" I/Os per board. Then all you need is an Ethernet port to do as many I/Os as you wish. Regards, Willy _______________________________________________ LinuxPLC mailing list [email protected] http://linuxplc.org/mailman/listinfo/linuxplc
 
C

Campbell, David (Ex AS17)

Hugh Jack wrote > I would suggest keeping the steps small and simple. > First, why not a simple board with optoisolators for > 24Vdc inputs, and triacs on outputs for 120Vac outputs > that plugs directly into the parallel port - no cables. Just a *tiny* little point here, just make sure that the PCB tracks can handle 220Vac[*]. Then the incremental change for Europe would be to replace the triac with one rated for the higher voltage (most triacs have the same package style). David Campbell [*] Aus power standard is 240V while European standard 220V. The specs for Aus have a much tighter voltage margin which allow it to be compliant with the European standard! (eg: sits in the top end of the band). _______________________________________________ LinuxPLC mailing list [email protected] http://linuxplc.org/mailman/listinfo/linuxplc
 
Top