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You just need to sample the current several times faster then you are switching. The teensy adc can easily sample fast enough as long as you use DMA sampling. You can also take the measured current as a voltage and filter it down to the average. What specifically are you trying to accomplish...

The down side to the Nextion is the atrocious serial speed (max per datasheet is 115000bps).

Here is an example of how the connection would normally happen and what voltage we would expect. This follows Ohms Law and Kirchhoff's Voltage Law, no matter what you do you cant break these laws. On the Left the Battery is the GND/0V point. On the Right the Motor/Alternator is the GND/0V...

Now I see what your doing. Rotating the shunt does not produce the same result as actually running current in both directions. You will not get the same result in the complete system. In the correct configuration your gnd/0v point will never change. I'm at an airport right now, I can toss a...

Differential mode will probably help but will not work with negative voltage, Steve0 can you provide any schematics on how the teensy and shunt are connected. Without some isolation or separate sources I dont see how your not seeing negative voltage.

Please post on sketch of your circuit, the way you describe is fishy and could lead to magic smoke eventually. Any voltage applied below -0.3v will damage the micro due to the internal protection diodes on all pins. The fact that your reading that shunt in that manner leads me to believe the...

@brtaylor, will there be support added for the extra pins? I take it most PJRC libraries would have issues with the extra pins....

Very nice, from experience you will have noise issues with the ADC's if you try to run SPI while sampling the ADC's which makes logging or running small screens a pita. What I ended up doing was using an external spi adc with isolation between the Teensy and the SPI ADC. With careful routing...

That may work unless the noise is induced on the ADC via the Data lines, which is something I have seen with SPI coms to ILI9341 and reading ADC's with/without external ref at the same time.

The solder blob at VUSB looks dangerously close to one of the micro usb ground tabs.

The LSM303AGR is the latest version of the chip, not sure when the rest will go obsolete. If you want something lower cost but reliable try the Pololu breakout.

Sadly, I normally run out of Pins, Special Function pins and most often.... MEMORY.... :( on 3.6 projects

I would think its a timing issue, the default PWM frequency is 488.28Hz. Considering where it divides into the clock that is probably an ideal value. 75Hz is 6.51 times smaller then 488.28 so there is some left over that does not divide out correctly. Take a look at the PWM & Tone page.

True defragster, he did say something along those lines, weather it was translated correctly is a different story. At the point he posted I think it was more in frustration then anything else, he came here and was met with nothing but frustration. It was pushed off topic and has stayed there...

lightcalamar, welcome to the forum. First. I think when crushing new people to the forums to save on spam becomes a thing then maybe the way spam is handled should be reconsidered. Second. lightcalamar is not a native English speaker from what I can tell from interactions on other forums...

Here is an updated basic schematic. There are Op-amps on the market that are rated for 36V continuous, that would be plenty for an 8S pack in case you want to future proof. As a BMS this is probably not the perfect solution, as part of a charge/balance controller it should provide pretty...

Correct as a battery monitor the circuit I provided would unbalance the pack. For the High accuracy resistance measurements it would be very good. Some of the uneven discharge could be adjusted by changing the resistor values of each section.I think instead adding a second op-amp at each...

No reason why this should not work. Just hook it up to an ADC and your done. This could be done with the test board I created since I set up the dividers to be changeable between different configurations. Just make U7 a +/- 15V version instead of the +/- 12V and use decent opamps, the LM324...

Or 16bit single ended ADC with all channels scaled to 27-30V will give you sub mV readings. It really depends on cost. I have an 8 channel 16-18 bit 400kSPS ADC breakout for the ADS8698 series. Depending on what chip you use it could set you back almost $30 just for the ADC.

1. No real practical way of doing this unless you went to invest in a large array of relays with an isolated supply to power the Teensy. 2. Unless you invest in high accuracy resistors your going to be stuck with 1% resistors. The trick is to calibrate your adc channels with the offset and...

Been pretty quite the last few months on this, work has been keeping me extremely busy along with life in general. I significantly reworked the design a few weeks back and added Isolation between the analog and digital sections. Then I ran the BOM and added up the costs, as it stands right now...

Interesting. Whats the output load on the Murata 78SR and what does your input voltage look like at start up? We use the 78SR's at work and I also use them at home. They are very handy and fairly clean even without external caps. We have been using them as drop in replacements for 7805's on...

Running 12 hours days at work right now so cant give actual code pieces but. You did not change the number of samples per reading you are doing so by default 4 samples are taken per value output. Your buffer is really small. The teensy has a massive amount of ram, no reason to bottleneck it and...

Some examples of DMA ADC operations can be found here. The speed at which you can send is largely limited by the PC. You will want to send packets of several readings at a time or the pc will choke the Teensy's serial. Also at higher rates the Arduino serial monitor has a bad habit of running...

You wont resonably be able to use anything above 13 bits. The 3.6 can sample much faster then 100-150K, it depends on what settings your using. Bill Greiman getting 3Msps

I dont see anything that stands out. You should consider connecting DACB pins even if you don't connect the output to anything. Some devices don't like floating pins like that. There is also a warning in the Absolute ratings section about the -15V rail. If it ever rises above +0.3V it could...

Well consider reading the datasheet again. The example code which you did not post but provided a link to is designed for a different kind of device with different data requirements so naturally it will not work. The MAX532 needs 24 bits transmitted to it, first 12 bits would be DACA and...

I have a few of the PJRC Touch Screes it has 4 led's so max current is 80mA. You can safely run the back-light from 3.3V, technically if you want the same brightness using 5v as running from 3.3V you can use a 22R from 5V. There is also a built in 3R9 resistor on my LCD's going to the...

manitou is correct. Technically it defaults to 3V3, so unless at some point you change it to the internal reference you can just comment out that line.

Should be compatible with the FT8XX series from FTDI. Same series used on the Gameduino. Got a pair of 7" FT811's I have been playing with. Pretty nice little chip, the Gameduino library can be a little confusing but there is a few active fellows working on a fork that supports Teensy's. Only...

Its dependent on what frequency your running and what settings your using... At 96Mhz with the default settings per ADC you can see anywhere from 4.08uS to 5.5uS depending on the resolution for the ADC you select.

I have not had any issues with APA102's being driven from 3.3V on T3.2 and T3.6. Have you tried running any examples from the library?

45kHz is 22uS per update, most screens I have played with cant even change 1 letter on screen in that amount of time. You really should look at running them on their own SPI buses.

Isn't xoscope just a microphone input hack?

The stock library should have that since that's where that example comes from. There are other libraries out there with optimizations for Teensy, but you can run several stock examples without the SD Card. Try changing GD.begin(); to 0 - 3. You may find one option works better then the rest...

I spent a few hours playing with the HotMCU FT811's I bought a few months back and got one running on a T3.1. //#include <EEPROM.h> #include <SPI.h> #include <GD2.h> #define PDNPin 8 void setup() { pinMode(PDNPin, OUTPUT); digitalWrite(PDNPin, HIGH); delay(20); digitalWrite(PDNPin, LOW)...

I guess I can drop my two cents in. I actually gave up trying to put the Teensy 3.6 on a breadboard when I saw it, instead I used long pin headers for the outside pins and normal pin headers for the underside, and I invested in a few hundred Dupont wires with different configurations. Of the...

Yes it appears that the base of the opto transistor is provided for certain cases but is not needed in this case. The LED inside the opto provides the energy needed to power the transistor when current passes through the LED. The 3.3V side will draw around 2mA. On the right side the gate...

If the datasheet you provided is the Mosfet you have then you can drive it with 3.3V. Doing it with the Teensy is probably not the safest thing you can do thou. I would use either a logic buffer IC, a smaller Fet / BJT or an optocoupler. Most of these options will allow you to drive the...

If you can handle soldering 0.5mm pitch pins and 0603 parts I can send you a blank ADS8698 breakout board and a parts list and you can build your own breakout. Provided your somewhere that USPS delivers to. I built the board solely for testing and have learned a few things from it. I may take...

How much noise is being created on your samples when you write to the SD Card? My experience so far with Sampling ADC's and trying to do SPI transactions at the same time have forced me to use an external ADC. It did not just create random noise either it forced all the samples in one...

The resolution will be based on the accuracy of your feedback, SMPS are primarily analog circuits. Depending on the voltage range of your supply 16bits will be tough to maintain. How much current do you need?

If your goal is a variable supply why not avoid reinventing the wheel and just use the Teensy to adjust the feedback voltage to an existing SMPS design. You can do the same thing to a linear regulator after the SMPS to further reduce noise.

Progress was made :) Took a while but I have the LCD and ADC running on SPI0 and SPI2, the noise is not to bad so I don't believe I will spend to much more time with it. I doubt I could get noise down any more without going to full isolation of the ADC from the rest of the setup. Which I don't...

Well, you have given us no pictures, no schematics, no code. So its tough to have any idea whats going on.

Erm, its a 6V battery, it should be fully charged at 6.5V and dead at 5-5.25V, at which point you should probably disable the GPRS. Really draining a lead acid will shorten its life considerably. Its hard to say, if the Teensy 3.3V rail is falling into the 1-2V range its anyone's guess as to...

The only one I have experience with is the one I created for my CC Dummy Load in order to test the ADC before I commit to anything. The PCB will accept at least 4 TI chips in the same 4-8 channel range, with 14 to 18 bit resolutions. I am still trying to figure out if I can use DMASPI on the...

Just realized I never posted the latest schematic for the ADS8698 breakout board. I only had 2 major issues with the PCB. The first was I got the 3.3V regulator pins mixed up so I had to clean some mask off the 5V plane and solder the SOT23 on an angle. The second was the ADS8698 as I mention...

Hello Yannick, your project is definitely advanced. Your kind of hitting the same rough road I have been working on with my CC Dummy Load project. You will face several issues. To get decent ADC values you have to go to an external ADC since every time you write to the SD Card it will...

Looking at the ADS8881, you pull CONVST High (Chip Select), clock 8 times, then pull it low and clock 24 bits, then you have to shift your 3 bytes around to get the correct value. Here is a simple test sketch I made for the ADS8698. RST is not valid for your chip and the SPI.transfers I do in...