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Ok, so there may be more elegant solutions to the problem, but the below worked for me. Credit goes to the arduino forums. Change the top portion of the Multibus example from: to: Note, this is not as elegant as the original solution (simply define a array of DS18x20 pins and the program...

Hi guys and gals, I found a bug in the Dallas Temperature library example and I wonder if anyone here has a suggestion how to fix it. If you have the Dallas Temperature Library, load the Multibus_simple example. If you try to compile, the compiler throws the following errors...

Totally agree and I would add reading up on the hardware specs published by Freescale. The more I got into it, the more I realized just how unlikely it is that anyone gets remotely close to 16 bits of real ADC accuracy out of the MKL20 series of chips. I don't doubt it can be done but the...

Another option is to use a RS485 transmitter on one end and a RS485 receiver on the other end. Very resistant to EMI, cabling is cheap (ethernet or like twisted wire) and breakout boards are readily available.

I would check the ribbon connectors carefully. My guess is that one connector is put on with the correct polarity, the other one in reverse, sending power where it's not supposed to go. I would consider using female-female jumper cables (i.e. individual pin to pin connections) and see if that...

For full duplex with RTS/CTS, you will need 4 pairs of wire. I would implement it with two full-duplex RS485 chips (i.e. IL83071, among many others). One chip dedicated to UART/Serial, the other to CTS/RTS. Or, buy a single full-duplex RS485 chip with 2/2 channels for each end. Digikey lists 86...

I think of Easy Transfer as a STRUCT wrapper to transport a variety of variables. It doesn't do anything re: CTS/RTS, you have to implement that yourself. However, I really appreciate how easy Mr. Porter's library makes it to share variables among compatible MCU's. Even better, Paul has been...

I'm not against standing on the shoulders of giants - I do that every time I touch a computer! However, I wanted to impress on Luis that asking Paul how to subvert his income stream is likely a bridge too far. Paul is an awesome guy but I doubt he wants to spread the info far and wide on how to...

Let me get this straight... Paul develops the teensy ecosystem in conjunction with Arduino. You are leveraging Pauls work to create a boards.txt derivative for your chip. Your approach avoids the need for the bootloader chip, hence depriving Paul of income for R&D that allowed 1) to happen...

OK, tested it tonight - the version of a DHT22 I used appears to be an open-collector device - it could be powered at 4.7V (or whatever the VIN is on a Teensy 3.0) while the pullup resistor for the data line was attached to the 3.3V regulated output from the Teensy 3.0. I used pin 13 and...

Sounds like RS485 makes more sense then. There should be zero collisions on this circuit since the teensy at the cutting end will simply be sending a stream of DAQ numbers. Another option is to have the cutter only send data on demand from the controller. All collisions on a two-host system...

That's certainly one way to do it. However, I wonder if you have the polarities on the power jack reversed. Most jacks are positive on the inside, GND on the outside.

The answer to your question depends on two factors: the hardware and how you are using it. On the hardware side, the answer depends on the crystal / oscillator you're using and any compensation you may be throwing at the problem. I managed to get a standard CFS-209 RTC crystal compensated to...

All comes down to the power needed. If you need the 500mA that the MCP1825 can allegedly produce (with an ideal PCB layout and so on) then have at least 2 choices: 1) Find a more suitable voltage regulator that can handle the higher input-output voltage delta (i.e something like the LD 1117...

If this was my project, I'd opto-isolate due to the damage potential. Why risk a expensive computer or two in case something goes sideways between their power supplies as described above? If timing is critical, opto the outputs from the buttons themselves and run the same program, completely...

If the code requirements are modest then I would consider doing this project with two LC's. They are less expensive than a 3.2 and sound like they could do this project w/o issues. One LC would be acting as the master (doing the DAQ for the buttons) and then send data serially to the slave LC...

FWIW, I would also go down the path of the RS485 route. Shielded Cat6 cabling sounds like a good plan, i.e. 5V and GND on 3 pairs, the remaining pair using RS485. I'd go for a slew-rated RS485 like the ISL ISL83483/88) and EasyTransfer from Bill Porter to transfer the data. That way, you'll...

I'm glad I could help, have been helped here by others far more intelligent and experienced than I so many times... which is why this community is so dear to my heart. If I happen to see an update, I'll be happy to review it, just keep in mind that my time here can be lumpy - intense periods...

Yup. The add library makes life easier, Paul has also published some examples how to read analog values. It might be as simple as a voltage divider and capacitor from analog input to agnd. Something in the 0.01uF range as recommended by OEM or higher. Check out the voltage divider...

That's just awesome. If I ever tried that there would be nothing but blue smoke and tears. Congratulations for making it work!

I went over the schematic and see no issues with the connections between the MKL04 and the MCU. I would double-check them with a DMM (as well as to GND and 3.3V). Don't use the buzzer feature, just plain old resistance. Wondering though why VREFOUT was tied to GND. There is no resistor. It's a...

How about building your own? I made mine with a board from rocketscream (and there are many alternatives now), a Triac, some leftover mower parts plus a pizza oven.

Is there a particular reason you connected PTA6 on the MKL04 and PTA1 on the Teensy to GND? If USB-hosting is of interest, these wires should be attached to the ID pin of a 5-pin USB connector. However, the connector you chose has no ID pin. So PTA6/PTA1 should only be connected to each other...

I would start as follows: Hook up a Teensy 3.6 via the differential inputs to the strain gage and see to what extent the results match reality. Especially if you can use the built in PGA as an amplifier. If the results are OK, you can skip the need for an instrumentation amplifier. One thing I...

A 3.5 or 3.6 would certainly remove some constraints. DMA control of the ADC is not a trivial thing to implement. IIRC, the current ADC library doesn't... The best bet may be a 3.5 with onehorse NRF+ module from Tindie (verify it works with a 3.5!) combined with a strain gauge ADC on a...

A couple of thoughts. For one, I suppose you will have to mount the Teensy at the center of the hub in order to avoid adding a significant amount of strain on the blades, etc. from mass imbalance and so on. Additionally, you will need a battery that will sustain the ~30-100mA current draw of the...

AREF can be used with an analogReference(EXTERNAL) declaration for the AREF source to provide a more stable voltage, which in turn should produce more reproducible results. Pauls intent was the use of a voltage shunt diode, where the 470Ohm resistor provides a mA-level power source to AREF (see...

My suggestion would be a 2x4 pin header with jumpers that connect the mkl02 when you want it (with shunt jumpers) and which disconnect it when you do not. Your debugger pins are thus exposed for debugging as needed. IIRC, Paul has mentioned that he may program a disable pin feature on the...

Couple of thoughts: 1) Get a good soldering iron with a 'real' temperature controller, then dial it in for your particular solder. 2) Tip tinners and coarse brass to clean same are a must 3) Get a variety of tips. A fine tip for small holes like the CFS206 RTC crystal, a broader angled one for...

The ERV project is moving forward. Tonight, I finished up the first test board and verified it's basic electrical operation. As you may recall, the Leviton motion sensors live off a 24VDC power supply. The Windsensor, revision P, from Modern devices needs ~9VDC or so for good thermistor...

Some of these optical issues are easy to diagnose. The light from a visual light source should be very bright inside a house when it arrives at its destination. So bright, that the outlet will glow from the inside. From what I could tell, the electrician attempted a good install re: the...

In the US, you are far better protected from fraud with a credit card than any other means of payment. if your credit card gets stolen, you have a new one in 24hrs and you are not liable for losses. Try that with a debit card or Paypal.

I don't think the fees are the issue - credit cards siphon off 3% or more, depending on your revenue volume and so on. AMEX had a very public revolt in Boston circa 1995 when small merchants objected to 16% fees on transactions. Paypals fees are in the same league, as regular credit cards, IIRC...

I'd investigate what reputable local distributors are around in TW. Within a nation of ~21MM people, there ought to be enough demand for someone to have a store like sparkfun, etc that can source stuff and components.

The circuit you're looking for is described in the various application notes. The first question you need to answer is whether you want a isolated rig or not. MCP designs generally assume that the chip will be used in a isolated enclosure (electrical meter, for example). For cost reasons, they...

Best of luck. I hope that the resistances you're looking for are consistent enough from channel to channel to be useful.

Ask yourself a simple question: What is my time worth? Is dealing with even a small number of flaky IC's worth your engineering time, reputation risk, and so on? I'd suggest that the tiny $$$ savings pales in comparison to the risk. If your product success depends on that tiny savings, you are...

I don't have the means to test that. The hope is yes. I like to give GND multiple vias from each polygon in case the board house screws up and one of them isn't connected. You can eliminate the two via lines in the bottom of the board. Run a power line to the left of the USB connector down to...

I'd try to use a glue meant for plastics. Anything designed for holding PVC to something else. The hot glue can be useful as a temporary scaffolding.

I used to... and then realized just how bad it is. Now I lay out everything by hand. The only decent router companion I encountered for Eagle was the external, java-based push-pull freerouting: https://github.com/nikropht/FreeRouting That is a beautiful set of code, i.e. a router that respects...

FWIW, the above circuit uses a external voltage regulator, just like your layout. Note how there is a single signal on the b-plane, i.e. a little jumper under the MKL02. The rest of the board does the same thing. I used a vertical USB connector in this layout.

FWIW, I use this crystal: http://www.digikey.com/product-detail/en/ndk/NX2520SA-16.000000MHZ-W1/644-1093-1-ND Here is a sample layout of the chip. Note: VBAT and RegOut do not get decoupling caps, they don't need them. If you don't plan on using the ADC, you can skip the power-cleaning...

Hey Frank, Congratulations and it's amazing what you could do with the 3.6.

Saw your question re the crystal and you definitely violated the rules of engagement by running data lines across the crystal lines. Don't be silly. Buy the same chip as pjrc and put it in the same place. That allows you to drop the capacitors and you gain the benefit of a known good...

FWIW, I would change a number of things because I am a bit retentive when it comes to PCB design. This is the bottom half under a custom board. Note: 1) only one PCB trace crosses another on the b side (that's the only crossing for the whole board) 2) individual decoupling caps are close to...

The new subscription model is a sign of the times. Most every software package is transitioning to it, as developers (and owners) love the model: No longer there is any pressure to keep evolving the product, you simply keep earning revenue no matter what. Unless users revolt (and Intuit had a...

I bought mine at Amazon, see the link above. About $200. I figure it's a good investment for a project like this one where every connection is likely suspect. However, the visual tester ($20) works very well also - if the visual signal is strong, the DB losses are low. I guess it's good to...

Happy Ending after all. Suspecting that the confectioning of the fiber optics by the electrician was the problem, I replaced the SC connectors in the office. All went wrong with fiber #1, it kept breaking until the nub in the wall was all that's left. But fibers 2-4 work wonderfully with...

You must be German. ;) FWIW, I too am a Eagle user and have made peace with some of the weird quirks in Eagle. Still considering buying a full version minus the auto-router. I intentionally stuck to version 6.5 because later versions label errors on my parts that a supply house has no issues...

Anyhow, here is the current state of affairs. The TRV is back in its alcove, now I have to reconnect all the ducts, which is quite a challenge thanks to the small access hole I have to play with. I bought an inexpensive wind meter to compare the readings from the blue end of the unit (left) to...