nicholas_t. Posted May 29, 2003 Share Posted May 29, 2003 I found this piece of palm freeware on the net, it times and archives a gazillion processes and can even turn your enlarger on and off! <a href="http://www.jan-exner.de/software/fototimer.html">Foto timer<a/> Link to comment Share on other sites More sharing options...
rob_gruber Posted May 30, 2003 Share Posted May 30, 2003 How do you get it to turn your enlarger on and off? What type of input cables do enlargers take? (I've never had my own digitial timer only used them in rental darkrooms). That would be really cool. A cheap palm is cheaper than a digital timer and it would record your times too, I suppose. Link to comment Share on other sites More sharing options...
nicholas_t. Posted May 30, 2003 Author Share Posted May 30, 2003 I don't know and don't take responsibilty for the enlarger thingy. Something about if your pda has a serial connection. Link to comment Share on other sites More sharing options...
dan s. Posted May 30, 2003 Share Posted May 30, 2003 I've been using this program for nearly a year and highly recommend it (it was part of the reason I originally bought my PDA). Easy to use, versatile, good interface, small (56K on mine, with a bunch of processes set up). I've been using it mostly for developing film, for which it's well suited. The process-chaining feature is great, it allows you to define the unchanging parts of your workflow (stop, fix, wash) and easily stick different deveopment times on the front. It's also pretty handy as a simple interval timer, beeping at regular intervals for as long as you leave it on. I haven't yet used it to control an enlarger. The page says that it uses a serial port to control external hardware, so I imagine you'd need a power supply that can be switched on and off by a serial connection. Link to comment Share on other sites More sharing options...
rob_gruber Posted May 30, 2003 Share Posted May 30, 2003 Thanks.<br><br>This piece of Palm software looks interesting as well:<br><br><a href="http://home.eznet.net/%7Erlmsmw/">Go Pix</a><br><br>Might be time to buy a Palm to go with my Rolleicord, a nice combination of old and new. Link to comment Share on other sites More sharing options...
jorge_oliveira2 Posted May 30, 2003 Share Posted May 30, 2003 I've never seen circuits/diagrams of the Palm's serial port. But to connect to the AC network to control the enlarger requires some adequate circuitry - remember a darkroom is a wet place. Of course, it can be done; if I had the missing Palm details I would surely think about it (I'm an EE). Link to comment Share on other sites More sharing options...
dan s. Posted May 31, 2003 Share Posted May 31, 2003 I can't say much about Palm wiring (I'm a software guy). I have a serial port adapter for my Handspring, but beyond that, I have no clue.<p>I did find a site (<a href="http://www.cdegroot.com/photo/linuxdr/">http://www.cdegroot.com/photo/linuxdr/</a>) of someone who put together what sounds like a pretty useful darkroom solution. The zip file includes instructions on how to build a parallel port-driven power switch. Of course, not a pocket-sized solution (laptop at best), but something that could be fun to play around with. Link to comment Share on other sites More sharing options...
jorge_oliveira2 Posted May 31, 2003 Share Posted May 31, 2003 Dan After I posted I did a deeper search and found a circuit to lit a LED. From there, it takes a simple circuit to turn on and off an enlarger light and off and on a safelight (complement). Now, let's look for a Palm serial cable. Link to comment Share on other sites More sharing options...
nicholas_t. Posted May 31, 2003 Author Share Posted May 31, 2003 I've emailed Jan Exner, the inventer of Foto timer, and asked if he can give us a more clues as to the enlarger timer function of his software.<p/> Perhaps, if someone knows how to speak French they could ring him, his phone number is on the website. Just a thought... Link to comment Share on other sites More sharing options...
jorge_oliveira2 Posted May 31, 2003 Share Posted May 31, 2003 I've emailed him also. I've asked if was there an enlarger interface, and if not if he was interested in helping me with the SW side to do one. Let's wait for his reply. Link to comment Share on other sites More sharing options...
jan_exner Posted June 2, 2003 Share Posted June 2, 2003 Hi All! I am not familiar with hardware, so when I did Foto Timer, I just went through the Palm OS documentation, found that I could open and close the serial port, saw that it triggered the CTS line and was happy. I was later contacted by a guy from Germany who built a small box which can drive 240V equipment. As far as I know, there is just one integrated circuit inside. I can open it tonight and find out what that is, if you want. However, (I like starting sentences like that :-) I know that just pulling up CTS is very crude, and it probably eats up the batteries faster then neccessary. So, if anyone here has a better way to drive something, I would be happy to do the coding. Palm has a document describing the serial port if that helps. It is at http://www.palmos.com/dev/tech/hardware/palmhardware/electrical_interface(10-pin)signals.pdf Gruesse, Jan P.S.: You do not have to speak French to call me, I'm German and I speak English, as well :-). Link to comment Share on other sites More sharing options...
jorge_oliveira2 Posted June 2, 2003 Share Posted June 2, 2003 Hi, Jan - Thanks for your email and the link. - Re CTS - Is it a single command? You do one out to activate and another one to deactivate? I fail to appreciate why it would eat the batteries (with a single command).The 'classic' over here would be to activate RTS, but this maybe just nice code... - Re the box from Germany - I bet it's an optocoupler of some kind. That would be the standard solution. If you could inform the type it will help. Now, just an standard optocoupler would limit maximum lamp power of the enlarger, so I'm considering an extra chip to drive almost any lamp. Question - what about the safe lamp? If it's a very low power one, it does not rquires extra circuitry.I really can't define the boundary where one needs or not the extra circuitry, so maybe it should be there just in case. Cooments, gents? Link to comment Share on other sites More sharing options...
jan_exner Posted June 2, 2003 Share Posted June 2, 2003 CTS just goes high when I call a system routine called SerOpen and goes back down on calling SerClose. Since I have no clue about hardware and serial ports, I thought it was ok like that. But I recently was told that pulling up RTS would be the logical thing to do. If you prefer RTS, I'll change Foto Timer. I will see tonight what kind of optocoupler it is. I really can not tell wether a safe lamp could draw its power from the Palm. If it would be a LED, the answer would probably be yes, but I wonder if it wouldn't be nicer to do it properly... Basically, I can do the software part for whatever device you come up with, if you wish. I think it would make Foto Timer more interesting if it could do more sophisticated stuff than just turning CTS on and off. Link to comment Share on other sites More sharing options...
jorge_oliveira2 Posted June 2, 2003 Share Posted June 2, 2003 If all this routine does is to rise CTS, I think it's OK. If you feel that doing RTS is easy, it's Ok also. Re safelight - the Palm would not feed it. It would just be simpler from a hardware viewpoint if one could have just a one pole 'switch' to turn on enlarger and off safelight (I'm looking at home constructors). They would be series connected, and the 'switch' would shorten the safelight to turn on the enlarger. But then the safelight has to draw significantly less power than the enlarger - say, 15W safe and 100W enlarger. About more functions - pls suggest some - that's a question to anyone reading this thread. Link to comment Share on other sites More sharing options...
nicholas_t. Posted June 2, 2003 Author Share Posted June 2, 2003 What about using the infrared port? Most pda's have one. Perhaps, if the pda was not plugged into the house, many people (I for one) would probably feel safer. Mind you they probably wouldn't be tinkering with a palm then...<p/> Whatever is used for the enlarger timer, it would be great if it were available easily. Perhaps something generic and/or easily adaptable. FWIW, my palm has a USB adapter, and it's not a palm but a handspring. Fototimer works very well on it though.<p/> One thing Jan, I do use a lot of different formulas and have programmed them all in. I would love to be able to print each of them out. The notes function is great but it doesn't tell you what how the funtion being noted actually functions. If you catch my drift...<p/> BTW, this is very cool. Link to comment Share on other sites More sharing options...
jorge_oliveira2 Posted June 2, 2003 Share Posted June 2, 2003 Nicholas Infrared ports have two problems: It's more complex (I'm considering the average amateur homebuilder) and one must point the PDA to the enlarger interface box, maybe there wouldn't be room (where needed). As I conceive the system, there would be a small plastic box that connects to the power net (mains), the enlarger and the PDA. This PDA connection will be FULLY insulated (I've pointed that out in my first post as absolutelly necessary). USB - again, it's more complex to the homebuilder. But don't worry, there are cables that convert USB to serial for sale at Ebay, so... Questions: Is it acceptable to have batteries in this box (to save PDA battery; not mandatory, just convenient). Largest practical enlarger lamp? Any function sugestion besides turning on and off the enlarger/safety lamps? Thanks, Link to comment Share on other sites More sharing options...
jan_exner Posted June 3, 2003 Share Posted June 3, 2003 <p>Moin!</p> <p>Re CTS/RTS: I will try it over the next weeks. I do of course prefer to "do it right". If I can do it with RTS, I'm going to do so.</p> <p>Re One switch: Yes, that's what I think about. One single line that goes up/down and triggers whatever the box wants. I was thinking about using CTS, RTS and maybe also TX/RX in order to switch more than one appliance, but the box will be more complex like that, so let's stick to the easy stuff unless someone thinks that would be a killer feature :-).</p> <p>Re USB: I am inclined to concur with Jorge, too complex. On the other hand, most of todays Palms are USB...</p> <p>Re IRDA: I also think this is too complex/expensive.</p> <p>You could of course always buy something like <a href="http://www.ontrak.net/ADU200.htm">http://www.ontrak.net/ADU200.htm</a> (not related to them, just found them using a quick google search) and do funny things with it, but I prefer to keep it so simple that anyone can build a switch.</p> <p>Re Box: the box should be connected to the Palm via a long cable. That way it can be mounted on the wall (out of reach of any liquid).</p> Link to comment Share on other sites More sharing options...
jorge_oliveira2 Posted June 3, 2003 Share Posted June 3, 2003 Jan Take a look at: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3028042555&category=15018 Looks long enought for me. I've ordered one yesterday (actually price is US$13...) Link to comment Share on other sites More sharing options...
dave_mueller Posted June 4, 2003 Share Posted June 4, 2003 Jan, If the Palm guys follow convention, you should be able to control CTR -or- RTS, but not both. If nothing is connected, simply turning the signal on or off should not use any power. It's the external circuit that will determine the power used. To keep power drain to a minimum, the first transistor should be a FET type instead of a bipolar. FET transistors have a high input impedance, and are controlled by voltage instead of current. A bipolar has low impedance and usually needs at least a few mA to turn on. Then use the FET to turn on a relay to run the enlarger and safelight. Piece of cake, even for a software person :-) Link to comment Share on other sites More sharing options...
jorge_oliveira2 Posted June 4, 2003 Share Posted June 4, 2003 Using a relay has it's advantages, but will demand an external (to the PDA) battery. Comments? Link to comment Share on other sites More sharing options...
_________1 Posted June 5, 2003 Share Posted June 5, 2003 How about incorporating F-Stop Timing in your software? Link to comment Share on other sites More sharing options...
denis_pleic Posted December 23, 2003 Share Posted December 23, 2003 For anyone stumbling upon this thread in the future, here's my addition:</p> I've actually built the relay, and have a short presentation (with a kind of schematic) on <a href="http://open.hr/~dpleic/photo/photo.html">my page</a>. </p> In short, it works great! </p> Regards, </p> Denis Link to comment Share on other sites More sharing options...
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