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

I want to have a number of 1-wire 1820 sensors thruout the house, and want to minimise the cost of those so I can use them wherever it makes sense to have one like in all the fridges and freezers etc so I can do basic stuff like alarm on out of acceptable range etc.

The obvious way to do those physically is to use phone extension leads with RJ11 connectors on each end. Just cut them in half and solder a 1820 on the bare end of each half. Then just connect them all in parallel using standard RJ11 sockets on vero etc or in punch down blocks etc.

What I want is a fully assembled USB/1-wire converter that can be used to interface those to the PC.

I also need at least a decent driver that can be used from VBA from Access or Excel etc.

The stuff thats obvious on the web mostly dont use such unpackaged sensors. Cant see any reason why its not possible tho.

It would be desirable to be able to use any standard

1-wire sensor ics too, but not absolutely essential.
Reply to
Rod Speed
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Hi

Would suggest having a look here...

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HTH Frank

Reply to
Frank Mc Alinden

Frank Mc Alinden wrote

Yeah, I already had done that before posting. It wasnt at all clear if their product can do that tho.

And they dont appear to do the software side either.

Reply to
Rod Speed

Did you already take a look to :

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I have no idea of how it works, but seems to be in line with your expectation.

Hope it helps

Thierry

Reply to
tparent

Nope.

Trouble is that that's serial, I need USB.

Reply to
Rod Speed

Frank Mc Alinden wrote

The problem is that

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that you cant just add a swag of 1820s in parallel to
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Reply to
Rod Speed

I think you have two choices: 1. Purchase an engineered set of matching products, such as those in the links below; or 2. Build your own.

In order to do #2, you will need to understand more about the 1-wire protocol and wiring options than you seem to do at present. Have you read all of the appnotes and forum posts at the Dallas/Maxim site?

I have four temperature sensors (DS18s20) currently logging using this:

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Reply to
Byron Hynes

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Here's a third, choice that solves the multiple string problem. This assembled board is available for ~$55 via PayPal from Dr. Peter Anderson

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I have one and can recommend.

It is designed to read and control *eight* strings ("runs") of 1-wire temperature, dual 32-bit counters and quad-input 12-bit analog input devices.

Nothing else comes close to the versatility and low cost -- and for a good cause (helps Dr Anderson's students). Dr Anderson also sells many other devices including a USB -> RS-232 converter if you need it.

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... Marc Marc_F_Hult

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Reply to
Marc F Hult

Byron Hynes wrote

Or 3. Find a USB/1-wire adapter that does what is necessary to allow the 1820s to just be plugged into the 1-Wire bare.

Cant see why that should be any problem design wise.

Yep, and decided that its perfectly possible to have a device that will allow a string of 1820s to be plugged into it.

I was hoping someone chose to do that with their USB/1-wire converter.

I think it makes more sense to use the 1-Wire system the way it was meant to be used.

Reply to
Rod Speed

Trouble is that it isnt USB.

And it must be possible to do a USB/1-wire converter that operates the same way.

Dont need those. And it makes more sense in my situation to use 1-wire devices for that sort of stuff.

Thats arguable given that a USB/1-wire converter that can drive a string of 1820s should cost about $30 fully assembled.

Yeah, I've used him in the past, just doesnt have what I need in this case.

Reply to
Rod Speed

Perhaps it is just that I'm tired, but are you looking for an "I can solder" solution or an "I can't solder" solution? (I need more sleep.)

For the first:

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Reply to
No

Or just add a usb -> serial converter to it. Dr Anderson has a lot of interesting boards but they are designed to be simple to interface to so that they can be used as teaching tools. A lot more computers and controllers will run a serial interface than USB.

Reply to
B Fuhrmann

Likely.

I would have thought that was clear from 'What I want is a fully assembled'

While I can and do solder, I was hoping someone had designed their USB/1-wire converter/adapter to provide enough 1-wire power to be able to handle a decent number of 1820s as supplied.

If I cant find that, it would be no big deal to have a single extra bit between the converter/adapter and the 1-wire bus that provides that extra power and I am happy to solder that up.

Cant see that that is a very viable approach. It makes more sense to use a standard USB/1-wire converter/adapter and do something to provide some more 1-wire power.

Reply to
Rod Speed

Your quest seems to have evolved, post by post into

a) multiple 1-wire channels (= "runs" = "strings") b) controlled/read via USB c) "should cost" =< than $30 d) price including software "drivers" e) in a single pre-constructed device (i.e., not USB-->RS232 converter + RS232--> 1-wire). f) you do/don't want 1-wire devices that aren't temperature sensors

Which gives (me) the impression that you'd rather pose the problem than solve it.

Peter's excellent, affordable solution is an 8-channel USB-RS-232 + PIC->

1-wire.

Maxim also makes the DS2482 IC2-> 8 channel 1-wire IC, but one has to get from the PC to the IC2 interface which requires at least one more chip to meet your stated need.

There aren't any 1-chip, USB->1-wire with multiple channels at this time as best I know. Since you added the requirement of $30 cost late in your evolving explanation of needs, consider buying 8 of your (hypothetical?) $30/channel, one channel USB->1-wire converters for a cost of $240. Peter's actual (not hypothetical) solution of USB -->RS-232 + PIC --> 8 channels

1-wire might be more attractive to you in that context.

Eight DS2490 USB to 1-Wire Bridge Chip's might fit in your budget but you wrote that you wanted something that was already constructed ( and so ditto with the DS2482-800 Eight-Channel 1-Wire Master).

(Fer hoots re-read your posts and responses for:

1) the inconsistency(ies) between what you wrote in your original post and your response above (2 points) 2) the pertinent fact(s) about PHAnderson's offerings that you misunderstand/represent (2 points) and 3) the additional requirement(s) you added after the original post requirements (2 points).

Seven points gets you a 'B' ;-)

Marc Marc_F_Hult

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Reply to
Marc F Hult

Is the "extra power" that you need an increase in voltage, current, or both? Or do you mean something else by "extra power", like extra connections? Or what?

Are you saying that you need multiple independent 1-wire buses, or multiple connections to a single bus?

Reply to
Huey

B Fuhrmann wrote

Rather more elegant to improve the power to the 1-wire bus instead.

If its actually necessary. It looks rather like his system doesnt do anything special to each 1-wire string power wise and it works fine anyway. Hard to be sure tho, no circuit diagram.

And are rather dated now on that serial/USB choice.

Sure, but serial has some real downsides now.

Reply to
Rod Speed

Marc F Hult wrote

Only in the sense that if I cant find a USB/1-wire converter/adapter that provides enough 1-wire power to be able to run a decent string of bare 1820s, it makes more sense to beef up the 1-wire sting power with a bog standard USB/1-wire converter/adapter than to do anything else.

Nope, I never said that. A single one of Pete's strings would be all I need.

That was in the original.

Never said that.

Or that.

That was in the original too.

Never said that.

More fool you.

Makes more sense to beef up the 1-wire sting power with a bog standard USB/1-wire converter/adapter

I clearly said that I want to run a string of 1820s in the original and its clear from Pete's system that that is trivial to do.

See above

No I didnt.

Makes more sense to beef up the 1-wire sting power with a bog standard USB/1-wire converter/adapter

If that is actually necessary. It may well be that a string of 1820s would work fine on the bog standard USB/1-wire converter/adapter

And that is essentially what I was asking, whether anyone had done that and found it worked fine.

Nope, I only need just one of his strings.

Thanks for that completely superfluous proof of what a terminal f****it you have always been.

Reply to
Rod Speed

Huey wrote

Its more complicated than that with 1820s.

Pete Anderson appears to do nothing special, using the parasitic power mode for the 1820s, but he doesnt say that too clearly.

The other possibility is to just have an extra wire in the

4 wire phone leads to the 1820s and provide say 5V down that if there is a problem with just parasitic power.

See above.

No, I was hoping to avoid that. And it appears from Pete Anderson's approach that that should be fine.

Yes, like I said in my original.

Reply to
Rod Speed

This thread is a good instantiation of the rise to hegemony in usenet of the lower quartile ...

To summarize:

1) The four-conductor RJ-11 plugs that the original poster suggests are conventional and useful for 1-wire installation. However 8-conductor RJ-45 plugs and jacks are ubiquitous so they would seem preferable in many situations especially considering that dependable whole-house 1-wire distribution sh/would best consist in multiple channels (see below). A 4-conductor RJ-11 plug fits into a RJ-45 jack, so RJ-45 patch panels, available for less than $1/jack on eBay, provide a flexible, dependable, inexpensive solution that is adaptable wiring infrastructure needs other than 1-wire (audio signals, audio control, RS-232, video, computer network, and so on).

2) Twisted-pair wiring (eg CAT3, CAT5) is preferred to non-twisted-pair especially if a whole house is to be wired as the OP proposes. The twisted pair provides better immunity to noise and more constant impedance than the ("satin") telephone wire suggested by the OP. The use of non-twisted pair wiring such as what is connected to the telephone cables that the OP proposes seems to be asking for poor performance if used for 'long' distances. Also note that some phone cords are stranded and may include cloth-like fibers making them difficult to solder and durn near impossible to punch down (and so are potentially unreliable for these reasons).

3) Best practices for Maxim/Dallas 1-wire does not include multiple channels (= "strings" = "runs") on a single driver. However the OP perserverates on this topology, perhaps because he under the mistaken impression that the only issue is available power for the sensors. T'aint. Others has suggested that he inform himself by reading the 1-wire documentation, but that doesn't seem to be his MO.

4) Maxim has a DS2482 IC that is designed to drive multiple channels. Dr Peter Anderson www.phanderson has developed and sells nifty, inexpensive PIC-based systems that also drive multiple channels. OP has been repeated referred to these resources by respondents, but doesn't seem to 'get it'.

5) Despite what OP writes, Dr Anderson's site does indeed include schematics and explanations for the devices in question.

6) Despite the OP's imperviousness to the concept that USB, RS-232, 1-wire and I2C all involve serial communication and that real devices (whether in one package or not) necessarily involve translation betwixt them, a USB -->

RS-232 converter + PIC--> multi-channel 1-wire solution (such as Dr. Anderson's) would meet his need. The multi-channel IC offering from Maxim/Dallas has I2C input and so needs a USB front end to met the OP's needs.

7) Despite what the OP now claims, reasonable people reading carefully would conclude that he is looking for a pre-built device that includes software drivers for about $30 or less. I don't know of any that are multi-channel and am reluctant to recommend a single channel implementation of what he proposes. It could be done, of course, by daisy chaining each of the strings through a hub, ( IN1-->OUT2 -->IN2-->OUT3-->IN3 etc) but it simply isn't worth the aggravation of a flakey data acquisition system in my opinion. The cost difference of $20 or so is small compared even to the price of the sensors required by the system. When one also considers consequences of errors and time expended, the cost difference is trivial. Among other reasons, a single break or poor connection in a daisy chained system takes down the entire system. Multiple drivers and channels ("strings") isolate problems, are more robust than a single channel and are easier to trouble-shoot and generally more reliable.

8) It is generally trivial to adapt an RS-232 device to USB using an inexpensive adapter. This has been suggested by several respondents, but apparently rejected by the OP for whatever reason.

9) In the experience and opinion of many (myself included) the most readily accessible programming interface for 1-wire is an simple ASCII protocol that the hardware device understands such as those used by Dr. Anderson. This allows the hardware device to deal with 1-wire timing and electrical issues. The OP wants a USB "driver" for VBA, Excel etc (whatever he means by that). Three good, very different approaches/sources for communicating with 1-wire-aware devices are 1) Homeseer with plugs, 2)
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and 3) StampPlot
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(I've used them all and can recommend.)

HTH ... Marc Marc_F_Hult

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Reply to
Marc F Hult

Marc F Hult wrote

Wota f****ng wanker you are Hult.

To lie, actually.

I never ever said anything of the sort. I JUST said that that was the approach I PLANNED TO USE.

Basically because the wire is more flexible and convenient.

Not in the PARTICULAR situation I WANT TO USE THEM IN.

Separate matter entirely to what I was talking about.

True in spades of RJ-11 panels.

Irrelevant to what I want to do with the temperature sensors.

Pity I wasnt even discussing whole house wiring.

I wasnt even discussing satin telephone wire.

Pity I'm not using them for long distances.

Which might be why I choose to avoid using those.

Dont need to punch those down, I clearly said that I want to take commercially made RJ11 phone cords, cut them in half and solder on a 1820 to each of the cut ends.

What I use for the RJ11 sockets those plug into is an entirely separate matter.

See above.

I dont give a flying red f*ck what is 'best practices'.

I know that strings of 1820s work fine, particularly in the situation where most of the 1820s are reasonably clumped together.

That isnt even a word, you posturing f****it.

Nope, because I have enough of a clue to realise that it works fine for Pete Anderson and its documented in the Dallas datasheets too.

Best get that seems machinery seen to then Hult.

I dont want multiple channels.

And clearly advocates the use of strings of 1820s.

I was well aware of that before I even posted thanks.

It doesnt happen to be what I want.

You dont seem to get that strings work fine, Pete Anderson uses them fine, and so all I need is a USB/1-wire converter/adapter which drives strings of 1820s the same way that device of Pete's does, or add that to a commercial USB/1-wire converter/adapter myself.

Yeah, its just rather poorly organised.

Not as well as a commercial USB/1-wire converter/adapter which will drive the 1-wire the same way Pete does in his system.

I dont need multichannel. Like that or lump it.

Only fools like you. ALL I said was that since commercial USB/1-wire converter/adapters are available for less than $25, one which drives the 1-wire string like Pete's does power wise shouldnt result in a price more than $30.

I am also considering using a much more expensive lan/1-wire device. Its got some advantages like being more convenient to integrate with VBA into Access and Excel since its a standard http protocol device etc, but has some potential downsides with other than just

1820 support and is rather less flexible in that area.

I dont want or need multichannel.

I dont actually give a flying red f*ck what you might or might not recommend.

Clearly Pete Anderson has decided that strings of 1820s work fine.

Your opinion is completely irrelevant. Pete Anderson is clearly of the opinion that strings of 1820s are viable.

There are no cost consequences of errors. Or time expended either in this case.

It isnt daisy chained, the sensors are PARALLELED.

Not interested. I'm quite capable of trouble shooting a break in the paralleled config I plan to use.

Daisy chained aint what I want, basically because that involves a pair of wires to each sensor location. A star config makes much more sense given where the sensors will be located, in clusters.

Because it makes more sense to do something extra on the 1-wire side of the USB/1-wire converter/adapter if it wont drive the string of 1820s adequately.

I prefer to do it better myself. Essentially because that give more control with other 1-wire devices later.

Thats what the USB/1-wire converter/adapter does.

I didnt say that.

Not what I asked about. I want to be able to control the strings from access and excel.

Reply to
Rod Speed

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