1-wire to USB converter that can use 1820s directly

On one of my older machines we had need of eight serial ports for a bunch of terminals and various other I/O devices. I forget the brand (it was quite a few years ago that I did this) but I installed a PCI card with an RS485 port. To this I connected a port expander with 16 RS232 (convertible to RS485 but I didn't need that) ports. The operating system was THEOS though the kit came with a driver disk for Windows as well.

The entire system was extremely simple to set up and use. The hardware ran 24/7 for many years without a hitch. We sold the business and the computer system with it six years ago. To the best of my knowledge it's still running today. I wish I could say the same for some of my other PC equipment.

Anything is easy if you know how. I don't write code but folks I work with develop software for industrial PC's and they don't seem to have much of a problem. I'm not trying to belittle your skills, friend. But I think you're unnecessarily constricting your project by ignoring other possible solutions.

FWIW, some of the alarm system configuration software I regularly use requires a serial port and will not function at all using a USB-serial converter. Some of the other software functions perfectly with either type. What I'm trying to say is that nothing is 100% better or worse.

On another note, I haven't followed this thread very closely so forgive me if I got it wrong but did you indicate you plan to use telco cables (the flat "satin" stuff) to wire up this system in multiple rooms? If so, I'd strongly advise you to reconsider. That's an area where I have extensive knowledge and hands-on experience. You really don't want to try to use that kind of cable for permanent wiring of any sort. More importantly, you don't want to run it through walls (code violation). It's a royal PITO to splice, does not take well to being stapled in place and is not robust enough for anything other than it's intended purpose -- as a flexible cord to plug telephones into nearby wall jacks.

If that is not your intention, ignore the above paragraph. :^)

Dude,

You're all clearly unaware that we've received a personal visit from a legendary internet personality, Rod Speed.

When I mentioned "RS" to an Aussie mate of mine a few years back, I got the whole scoop. I'll add my limited wisdom inline:

"USB Only" is obviously a much higher priority requirement for the OP than most replies have acknowledged. If there's anything that's typical about Usenet in this thread, it's that a lot of answers that fall under the heading: "not *exactly* what that user wanted." If my mate's read of Speed is right, we can be sure, if nothing else, that RS knows *exactly* what he wants. That's probably pretty clear by now, anyway.

The state of PC and HA wiring is such that it's easy (for me at least, and especially my wife) to understand how someone could finally say "not one more f'ing wire!" I, too, am struggling with cleanly implementing similar systems and have no serial ports to spare nor a desire to add additional ports via PCI cards.

This sort of approach is fraught with peril, as the cliche goes. You are limited to what PC can talk to your net (got have a special board installed), gotta learn another OS (Theos or some other proprietary OS). A machine failure is a crisis. Rod obviously wants something he can maintain easily. Anything that requires a special board in a PC means "maintenance issues" and I've supported enough of them to know. USB-based means he can plug it into a laptop, a Mac, a PDA and lots of other things and *hopefully* run his sensor net without having to crack open a machine or buy cards or adapters. I can see why he's so hard over on demanding that as a requirement. It's incredibly important for CPU device "independence."

Know why? You probably never tinkered with it once it was set up and running. Those sorts of systems work fine once you've put in the time to set them up. But if they fail, you either need an identical spare or lots of qualified spare parts to really assure 24/7 performance. I think that's one thing the OP, Mr. Speed, has in mind.

Compaq, at its zenith, was selling wonderfully overbuilt machines with connectors rated for 10X what was then "industry standard practice." I marvel at the sturdiness of some of the old PC "iron." It doesn't, however, have a whole lot to do with the OP's USB requirement.

Still, performance doubles every few years so longevity isn't as big a factor as it would be in a car. I would love to see my gas mileage improve the way PC clock speeds and peripheral throughput has. I would buy a new car as often as I bought a new PC if it did. IMHO, longevity is not a big requirement of the OP. I would say his USB requirement is actually a way of factoring in getting a new PC and being able to use it to control the net right out of the box, without adding a serial IO card.

You should have stopped right there. I know how to rebuild a VW engine. That doesn't make it easy in the slightest. If you don't write code, it's really a stretch criticize his code-writing ability. I don't do much programming, but I know that experience ranges wildly. If he wants to stick with standard, easy to understand and probably easy to port IO routines, well, that's clearly his choice and one I would be likely to make as well.

The OP is really the only one capable of commenting on the mix of factors that dictate his choice of SW. He's reiterating how important "standard" is to him in his design specs. Still, you're not listening!!!

Perhaps you aren't, but I'm betting he'll take umbrage. He's explained his requirements to the point of perseveration. (-: Disparaging his programming skills, however "gently" isn't likely to get a positive response. I'll bet it contains the "F" word at least.

And he should care what you think about his project exactly why? (-:

I don't want to sound mean, but I see so many newsgroups where the responses just get farther and farther away from the specs that I feel I have entered the twilight zone. I hear that "doo doo, doo doo" music right now. He wants a USB solution that he can program in VBA in a non-exotic sort of way. Pretty simple. It may not be realistic, given some other constraints on the project, but that's what I expect he came here to find out. There have been a number of posts that I think have been very helpful, but in the end, he's the one who gets to decide if they were.

This is probably one of the many reasons the OP demands a straight up USB solution.

Interestingly enough, from my read of your comment, you're *exactly* backing up the OP's reasons for NOT wanting anything BUT a USB solution. The more intervening HW or SW objects, the more chance that one of them will not function correctly. The same is true for any non-standard SW treatment.

This may indeed be an area where the OP should test assumptions before going much further. I suspect he may have already done the testing, but my experience with cutting and soldering those cables has been bad. Maybe Ozian RJ11 cables are different or he's got a batch of cables he knows he can work with. I suspect by the time he gets this far down, you've already lost much of your ability to persuade him. :-)

I hope he expands on the RJ11 cabling issue. I can see why he wants to use the cable - it's pretty unobtrusive as far as cables go, but it may be harder to work with than he's expecting. If he's got a solution to what I have found were to be the most unsolderable wires on earth, I'd like to learn it.

-- Bobby G.

For software on the PC there is absolutely no difference between a serial port on a PCI card, a virtual serial port (such as those used with USB-serial or those used with TCP/IP serial servers). They are seen as if they were serial ports on the motherboard. The advantage is that legacy software can make use of them.

One potential glitch is that legacy software may only support COM1-COM4 while the ports may be identified as COM1-COM99 (you can rename them). If you are writing your own software, it's fairly simple to enumerate all of the ports and make them available to your software - do a Google search on "VB enumerate serial ports". You should be able to use the same code in VBA.

Another potential glitch is that USB-serial converters are not all created equal. Some do not handle the handshaking lines. The only fix is to use one that does. The CP2102 handles everything.

The CP2102 is 5mm x 5mm and requires only 2-3 capacitors. It's capable of very high bus speed and a very high serial baud rate.

I agree that a standard USB/1-wire adapter is simpler but it doesn't appear there are any that are self-powered. It should be easy enough to modify your Elektor adapter to use a separate power supply. +5V regulated switching supplies are readily available. I've posted here about one that I've tested to be trouble free as far as causing X-10 problems. However, you may have problems with voltage drops if sending it very far over a wire in a telephone cable, especially one that passes through a modular connector or two at each node.

Robert L Bass wrote

Done that myself in the past.

Its clearly a lot cleaner to use one of the existing USB ports than to need to add another PCI card to support serial ports.

And that approach isnt even feasible with a laptop.

Nothing like as simple to setup and use as a commercial USB/1-wire converter/adapter if that will do the job.

Likely a commercial USB/1-wire converter/adapter would be just as reliable.

Some things arent.

They likely arent using VBA in access or excel.

I'm not ignoring them, I considered them and decided that its clearly a lot simpler and cleaner to use a commercial USB/1-wire converter/adapter if that will do the job.

And that approach has rather more future too.

Yep, some systems are notorious for not working well with those.

No news to me. What I care about is whether the simple and clean approach of using a commercial USB/1-wire converter/adapter would work. No evidence currently that it would not.

Nope. I did say that I plan to use RJ11 extension cables cut in half with an 1820 soldered to the cut ends in a star configuration, not in multiple rooms, maybe a couple of clusters. Certainly not the 'satin' type of conductors tho. I've already checked that the extension cables I can get cheaply and easily just use normal stranded wire.

It clearly works quite adequately for phone extension cables.

And I have used something similar for the basic phone service, tho again, not 'satin' wire, just solid wire in a twisted config in a round cable, usually used for internal phone wiring, but in my case its on the floor from the point of connection of the phone service, down thru much of the house, and its been working fine for decades now. I did that as a quick and dirty approach when the built in phone wiring failed and I was too lazy to work out where it had failed with poor access to the ceiling because its a flat roof.

I've been using that for DSL fine for quite a few years now.

I dont give a damn about codes. I physically built the entire house, did all the electrical wiring, illegal in my country, and got a licensed electrician to claim he had done that.

Yep, which is why I use the stranded wire form instead.

I dont ever do that.

Too late |-)

Robert Green wrote

You have indeed |-)

Yep.

Yep |-)

Dunno, only you appear to have noticed.

I dont care about that so much, see below.

Yep.

Yep.

Yep.

Yep.

And use the laptop which doesnt have any serial ports at all for convenient debugging etc too.

And the PVR doesnt have any free PCI slots, basically because its got 4 digital TV capture cards and a lan card and a decent dual head video card because I use that to play the captured video on.

I might well decide to do the logging and control on that PC since its got plenty of spare cpu resources when when capturing digital TV 4 channels at once and playing one too. Basically because that will be on the UPS and nothing else really needs to be.

Yep, makes life SO much more convenient if something dies, and for convenient debugging using the laptop etc.

Yep.

More being able to use it on any of the available PCs trivially.

Yep, a decent modern ActiveX control is by far the most convenient thing to use in Access and Excel.

It didnt actually, came close tho |-)

And my programming skills are fine, I just prefer to save time with a decent ActiveX control if one is available.

I did in fact in the past put the effort into a special purpose serial port and a driver of my own used from Access to load data into a digital watch which has a serial port. That was in the days when there was no real alternative. Nowdays I have a much more fancy system using a java cellphone with IR and bluetooth and load the data into that using a much more salubrious approach than a serial port and get the big advantage of no farting around with a physical connection at all anymore.

Its just not practical with multiple temperature sensors if you want them to be as cheap as possible so you can have them wherever you might want a temperature at some time.

Precisely.

They did help me to decide that a commercial USB/1-wire converter/adapter should work fine, and at most may need something a little more fancy added on the 1-wire side to say provide 5V to the 1820s instead of using parasitic power.

Yep.

And more hassle getting it working too.

Yep. Works fine with the RJ11 cables I can get for peanuts.

The 'satin' style is seen, but it isnt all that common and you can usually work out which those are just from the physical appearance and feel of the wire used.

Yep.

Yep.

And is quite convenient for stuff like the fridges and freezers, it'll go past the door seals fine.

I do that already with those indoor outdoor LCD temperature boxes from china, just run the outdoor wire thru the door seal.

I had previously done quite a bit of temperature logging in a professional situation by soldering LM335 sensors to what we call figure 8 two wire power cord. I used that basically because its so robust you can drive vehicles over it repeatedly without any problems.

Nope.

Just use the RJ11 cords that have stranded wire in them.

If that isnt available, just use solid wire telco internal cabling with crimped on RJ11 connectors.

The commercial leads are better because they are stranded and its less work to cut them in half and solder an 1820 on each cut end.

Dave Houston wrote

There is however a real difference between the standard com ports and the other ones from VBA.

Its more complicated than that in practice, most obviously with the IRQs etc.

Precisely and thats the problem with VBA.

I did in fact write my own driver for a special serial port that I kludged up using an ISA card with no IRQ at all, because it was a special purpose serial port that was only ever used for output only to a datawatch, but I dont want to go the serial port route because it would be convenient to be able to use the laptop which has no serial ports at all for debugging, and the PVR which I may well end up with the logging on because its on the UPS, doesnt even have any free PCI slots left, because its got 4 digital TV cards, a lan card and a decent dual head video card using all the slots.

It isnt in fact quite that simple from VBA.

Or dont bother with serial at all, just use a pure USB approach instead.

Cant see the point in bothering with serial at all if a standard commercial USB/1-wire converter/adapter will do the job fine, and I havent seen any evidence that it wont.

Going that route allows me to use the laptop for debugging, use the PVR for the long haul, and is a lot simpler and more elegant than any serial prot approach will ever be. With a lot more future too as serial ports sink beneath the waves.

Dave Houston wrote

They are all powered from the USB. No reason why not, plenty of 5V power available on the USB port.

And parasitic power of the 1820s should work fine, thats what Pete Anderson uses with his strings of 1820s.

Yep, but a commercial USB/1-wire converter/adapter is a lot cleaner on packaging alone.

Cant see why, the 1820 doesnt take much and I'd doing them in a star config, not a daisychain.

Happy to use CAT5 cable to the stack of RJ11 sockets for each cluster of

1820s.

Ahh! I see you've made my killfile in a previous incarnation. Had I recognized the name I would not have wasted my time.

Turning once again to your initial post...

1. You asked for "a fully assembled USB/1-wire converter". The DS9490R meets your criteria.

1. You asked for "a decent driver that can be used from VBA from Access or Excel etc." Maxim has two 1-wire APIs that are copiously documented at...

Whether or not they will run afoul of the FCC's anti-indecency crusade, I can't say. I don't do 1-wire so am not interested in delving deeper into the nuts and bolts. The COM version can be used from VB Script so it should be usable from VBA.

There's a link on the above cited page to a "developers list" which is probably where you should be spending your time rather than wasting the time of others here. If you're unable to make use of the APIs yourself, maybe you can find a reference to an Active-X control or find someone willing to create one via the developers list.

Now to add this new identity to my killfile.

"Rod Speed" wrote:

While not cheap, here's another approach.

Actually, IIRC, Rod_Speed, his other puppets and I 'conversed' in comp.home.automation before. He dug himself a hole and made it so slippery with his own corporal ejecta that he had to wait until he and the hole dried up enough for him to crawl out and away.

I just returned from 3 weeks in the Middle East including the West Bank where the reality that anybody can choose to become somebody by being disruptive is heavy in the air.

Marc Marc_F_Hult

There's actually some flat wire (really flat) that does this even better. It has the added advantage of being adhesive-backed, obviating the need for staples and the risk of injuring your wire with them. The stuff is primarily intended for use with stereo systems being installed in existing homes without attic / basement access. It's kind of pricey but it works very well and if you paint over it the stuff disappears. I don't sell it but if you're interested I'd be glad to locate a source for you.

Oh.

It would seem so.

That can be either a good or bad thing.

I'm not trying to argue that serial ports are better than USB -- only that they may be a viable option.

Actually, the THEOS operating system was a requirement of the central monitoring station automation software we were running. At the time there were no USB ports (or at least none that I was aware of). We were running a package called BOLD which automated the handling of incoming security signals on a multi-line alarm receiver.

Due to the critical nature of central alarm monitoring, everything in the office had a backup. We set it up so that I could throw a few switched, swap a few cables and be up and running after a total meltdown in less than 10 minutes. Our central station receiver, printers, terminals and computer system were all redundant. We even had two 4KW UPS units and two gensets though the backup genset was smaller and simpler than the primary unit.

That makes a lot of sense.

In my business identical spares are pretty much the industry standard. Not only that but they have to be capable of being turned on immediately -- no time to swap cards inside the PC, etc. A lot can happen in a few minutes when you're down. Larger, better financed central stations take this a step farther. Their backup systems are kept running 24/7. In the event of a breakdown the system has to give an alarm and "fail over" to the backup without skipping a beat.

Agreed. I can see the validity of what you're saying.

Oh, you don't? Hmm. :^)

I didn't mean to criticize him at all. In fact, I specifically said that was not the point. I was only trying to say that "easy" and "hard" are relative.

I'm listening. You've explained this point clearly and as I said above it makes sense.

One sage poster includes in his sig line the statement, "Umbrage is free. Take all you want". Usenet has something in common with driving a car. Participants often feel anonymous. That lends ease to expressing anger at lesser slights than "normal" folks do in other social situations. We've seen that in the visits of certain folks from another newsgroup.

There was no disparagement. For me it's probably easier to maintain a wiring system than for you (even assuming your skills in that area are above average) because that's what I did for a living for so many years. That does not mean that your skills are inferior. It only means that what is easy varies from person to person. What I really hate doing is integrating and maintaining PC hardware. :^)

He doesn't have to give a rat's derriere about my opinion. Nor do you. I shared an idea as have you. After reading your comments I can see why he's adamant about USB. No problem. This isn't a race to see who gains the most points. It's an open discussion forum where people with varying backgrounds, skills and opinions can share what they know/think/whatever. IMO (which doesn't have to matter to you either), this is a good thing.

Well, yes. But threads have a way of morphing, not so much because of Rod Serling's influence but because that is how conversation works. Unless there's a strict moderator tapping his podium with a ruler, most conversations tend to wander all over the place. As long as the subject matter is related to HA, I don't see that as a bad thing.

No argument here.

Same here. The design of the cable is intended to enhance tensile strength and flexibility with little or no thought given to compression, extension (soldering, punch down, whatever). They also are not expected to live very long. Many of them et replaced long before the phones to which they are connected die.

I made it clear enough that my comments were not intended as a slight. If he's so sensitive that he can't accept that, he loses. I'm not trying to gain anything. He is. I prefer not to assume the gentleman is as easily offended as you say. If I'm wrong, that's unfortunate but for his sake it would be good for him to take my (and your) advice about running wire.

I rarely curse but when once I broke out one of those cables and tried to solder it to a broken, cheap-o telephone I made an exception. :^)

Bob Green elaborated on your requirements and reasoning somewhat. I can see why you've chosen this approach. The only thing I'd try to steer you clear of is using flat phone cables. Regardless what you use, when you get the whole system up I'd enjoy reading about it.

Allow me to reiterate what I said earlier. My comments about what is easy were not intended as a slight. We all have different experience sets. 'Nuff said?

Not knowing Rod I won't comment about him, but the above sure says a lot about certain visitors from another newsgroup we all know. :^)

The HA7net turnkey etherent device looks very handy indeed, especially if Embedded Data Systems continue to add capabilities. The idea of modifying Linksys WRT54G's and other Linux based ethernet routers (topic in a different recent thread) to handle 1-wire and especially other I/O intrigues me too.

Some of their devices are quite pricey. Their 0-10vdc output at $100 a pop makes the 72-channel, 0-10vdc DMX512 interfaces I got from eBay for ~$100 'worth' $7200 each ;-)

This Kentucky company also sells the HA7E - ASCII 1-Wire Host Adapter. It is the only device supported by the 'free' Homeseer plug-in I mentioned earlier in this thread. For a $100, shipping included, one can purchase from them the HA7E and 15 (fifteen) DS18S20 temperature sensors. If one has installed conventional Cat-5 ethernet in a home, it is likely that there are extra pairs that could be pressed into service for a comprehensive temperature monitoring network using 1-wire. Calibrate all 15 at once and add correction via the data base (see paragraphs below).

The 'free' 1-wire HomeSeer plug-in by Ultrajones (Randall Jones) provides for logging the data to Microsoft Access 2003 (database included), Microsoft SQL 2000 and Microsoft SQL 2005.

Because the data from the 1-wire devices end up in a relational data base, it should be straight-forward to merge other data from other sources and sensors, including other 1-wire channels (="strings"= "runs") from other

1-wire interfaces/bus masters.

This neatyl solves the problem that most HA controllers -- however good they may be at responding to event-based rules -- are not well suited for logging purposes.

... Marc Marc_F_Hult

Robert L Bass wrote

Thanks Bob, a url of an operation that exports will be fine.

Robert L Bass wrote

Yeah, that's why I actually got some of those RJ11 extension cords and checked that I can easily get those which use stranded wire and not that satin stuff which can indeed be a complete pain in the arse to do anything with.

Once you realise the problem, it isnt that hard to work out from the appearance and the feel whether its that satin stuff or not.

Yeah, I always try to do that with more than trivial questions, post the washup once I have got there.

The obvious approach is to make up the clusters of 1820s on those RJ11 cables, see if it will work with one of the commercial USB/1-wire converters/adapters. Best to wire the 1820s up with 3 wires so I can use parasitic power or a separate Vdd line. If for some reason it doesnt work, because of the way the 1-wire bus is driven, I can alway cut to the chase with a

and either use that or work out why it drives the 1-wire better.

On physical packaging alone the commercial USB/1-wire converter/adapter is rather more convenient, even if I do end up doing something between the commercial USB/1-wire converter/adapter and the 1-wire bus power wise.

Sure, your comments were welcome. I should have said something about that satin phone wire in my original too. I was well aware of the problem and should have said that.

Yeah, tho I was essentially asking if there was more than just one flavor of those, particularly on how they drive the

1-wire bus, which might make a difference when driving a string of 1820s. Its clear from Pete Anderson's site and others that strings of 1820s do work fine, the only real question was whether the DS9490R will drive them as effectively as Pete Anderson's design which is known to work.

Yeah, tho I should have said more clearly that a decent ActiveX control is rather more convenient to use with VBA.

I was hoping that someone flogging those DS9490Rs like

would have a link to one. Havent found one yet tho.

It should indeed.

It isnt a new identity, I've been using it for decades now.

And I dont actually give a flying red f*ck what you do or do not choose to read.