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

["Rod Speed" <rod.speed.aaa@xxxxxxxxx>]

Robert Green <ROBERT_GREEN1963@xxxxxxxxx> wrote
> Robert L Bass <sales@xxxxxxxxxxxxxxxxxxxxx> wrote

> Dude,

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

You have indeed |-)

> http://www.google.com/search?q=%22rod+Speed%22

> 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:

>>> 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.

> "USB Only" is obviously a much higher priority requirement
> for the OP than most replies have acknowledged.

Yep.

> 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.

Yep |-)

> That's probably pretty clear by now, anyway.

Dunno, only you appear to have noticed.

> 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 dont care about that so much, see below.

> 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.

>> 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.

> This sort of approach is fraught with peril, as the cliche goes.

Yep.

> 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.

Yep.

> Rod obviously wants something he can maintain easily.

Yep.

> Anything that requires a special board in a PC means "maintenance
> issues" and I've supported enough of them to know.

Yep.

> 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.

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.

> I can see why he's so hard over on demanding that as a requirement.
> It's incredibly important for CPU device "independence."

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

>> The entire system was extremely simple to set up and use.
> The hardware ran 24/7 for many years without a hitch.

> 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.

Yep.

>> We sold the business and the computer system with it six
>> years ago.  To the best of my knowledge it's still running today.

> 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.

>> I wish I could say the same for some of my other PC equipment.

> 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.

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

>>> Serial ports done that way arent that easy to support in VBA
>>> either, support for non standard serial ports is pretty poor.

>> Anything is easy if you know how.  I don't write code . . .

> 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.

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

> 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!!!

>> 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.

> 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.

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.

>> But I think you're unnecessarily constricting your
>> project by ignoring other possible solutions.

> 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.

Precisely.

> 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.

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.

>> 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.

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

Yep.

>> Some of the other software functions perfectly with either type.
>> What I'm trying to say is that nothing is 100% better or worse.

> 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.

And more hassle getting it working too.

>> 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.

> 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,

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

> but my experience with cutting and soldering those cables
> has been bad.  Maybe Ozian RJ11 cables are different

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.

> or he's got a batch of cables he knows he can work with.

Yep.

> I suspect by the time he gets this far down, you've
> already lost much of your ability to persuade him.  :-)

Yep.

>> 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.  :^)

> 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,

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.

> but it may be harder to work with than he's expecting.

Nope.

> 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.

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.