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The first thing I would do is ensure that you send 64 bytes each time, since the USB packets for Serial contain 64 bytes the OS / USB Stack might delay for a few milliseconds in the hopes of filling up an entire packet, instead of transmitting a packet that only contains one byte.

Another method of converting the images into the right format is using GIMP, I made a post about that yesterday: 35575-Export-for-ILI9341_t3-with-GIMP, it's a free cross-platform image editor. Additionally the output contains the necessary width and height of the image, making it quite...

O_O That is indeed a major bummer :( I was going t say that you could drill the holes yourself with a precise drill-press, but I noticed that some of the via's aren't drilled either, which makes it quite infeasible :( Are they going to remake that panel and sent it out to everyone involved in it?

Yesterday I was working with the ILI9341 library and came across the pictureEmbed example. I quite liked the idea of using custom images into my project, when I got to the image conversion part I discovered that GIMP provides the required functionality out of the box. I thought I'd share this; a...

To ensure that you don't have to worry about separately uploading an server and a client program you might want to have both use the same sketch and depending on a digitalRead() drop either into server or client mode. Something like this (taken from my library's example): if...

By default the constructor is called with interruptPin=2, just to be certain, DIO0 of the RFM radio module was wired to Pin 2 on the Teensy? That pin is used to read whether the radio has finished transmission or has received anything. If that pin is also correctly connected, I'm at a loss... :/

The fact that setting the reset pin LOW is required could indeed have something to do with the level shifter, I for sure know it's not necessary when the reset pin is directly connected from a digital pin on the Teensy to the RFM module. @Bugeye60, yes, perhaps it's a good idea to give another...

Okay, I believe I have found a possible culprit... The hint was that the printRegisters() method is not available and the path you linked... The printRegisters functions is documented in the docs.... Somehow it is missing... so I checked which version is in the Teensy installation by default...

In theory this would indeed be possible... but imax (page 15) specifies 1mA, so you would hardly be able to see that the LED is lighted or not. In addition; even though one could probably create some register setting to create a constant output, perhaps reading the value of one of the registers...

@Bugeye60; About the capacitor, it does indeed look like it's already on board with Sparkfun's adaptor, so you should be alright there. Be sure to try setting the IRQ pin to input mode next time you work on this, because that is one of the major differences between Arduinos and Teensy 3...

Some tips from my side: If you have an SDR dongle (RTL2832U for example) you can use it to hear the data being sent, might help debugging. If you disable the sequencer and put it into Tx mode, it should continuously emit the preamble. Start with very short packets, the longer the more error...

On ubuntu 14.04 using a teensy 3.2 it finishes in 5.728165 seconds with no fails, I think I do see a problem however: In the loop function you call read_hash when you have more than one byte waiting. So there is some data waiting to be read from the serial port. Lets assume there are 5 bytes...

The barbecue lighter trick sounds very similar to 29441-Teensy-LC-resets-due-to-EMI, just holding the piezo element close to the PCB causes a reset. I could also just reset the Teensy (with blink, no external circuitry) by touching the program pin with a piece of wire of 20cm. The Teensy...

This is the Teensy forum, so it makes sense that everyone is writing about it. The Teensy is a development board with a microcontroller. So the Arduino and Teensy fit in the same category, but they are not the same thing. The newer Teensies use a 32 bit ARM microcontroller, whereas the Arduino...

I'm not entirely sure about this, the paragraph on the Nwake pin states: "NWake is a high-voltage input used to wake up the SN65HVDA195 from low-power mode. NWake is usually connected to an external switch in the application. A low on NWake that is asserted longer than the filter time (tNWAKE)...

The diode should be alright, I also use 1N4007's. I presume you mean you left out both D2 and R1? With those left out, so only Vsup (12v for my test) powered through a 1N4007 (D1 that is), floating pins on the MCU side I measure 8v on K-line. With the EN pin at 3.3v I measure 0.63V on the K-line...

The wikipedia page OBD-II_PIDs is quite helpful in this regard. But I have to agree, not all cars support the same PID's, mine does not support the fuel level like you mentioned. I thought this was peculiar, but closer inspection of the workshop manual revealed that the fuel sensor is not even...

I'll bite; The most commonly known project which deals with the OBD port is to the best of my knowledge the opengauge / obduino project, the original project page is probably obduino.ca (OBDuino has a wikipedia page), source code ported from google code to...

Cool, thanks for sharing that Constantin, I did not know that type of device. I have used the REF19x series from Analog Devices in the past, but the part you propose seems to be a lot easier to work with.

This is indeed correct, this is exactly how we determine the input voltage. Although I believe it's not available as analog reference, so calling it a reference would be wrong. It's called the bandgap channel in the datasheet, but what it's used for is beyond me. I'll leave the answer to this...

There was a hackaday post about a week ago that used that library on a Teensy LC: hackaday - turning-a-teensy-into-a-u2f-key When searching for that I came across this post discussing the cryptographic aspects: breaking-a-teensy-u2f-implementation, so definitely do not use that project as-is.

That library is full of AVR-specific assembly code, that is not going to work on the Teensy 3 with it's ARM chip. I am not familiar with a library that runs on Teensy that provides the CBC ciphermode with AES out of the box (anyone else?). (You could just implement the CBC cipher mode with the...

How large do you consider to be large? There is something called the MTU, which is dependent on the hardware in the communication path. Packages larger than the MTU will be dropped, it is usually 1500 bytes.

Seems to work fine (no errors observed in the console window, behaviour is as expected) on Chromium Version 37.0.2062.120 Ubuntu 12.04 (281580) (64-bit).

I finally had some time to work on this again. I made several changes to the OBD9141 class I mentioned in my previous post. It now uses a begin() method, making it much easier to work with. I modified the examples such that they work out of the box and added an example for use with Arduino UNO...

Definitely cool to know that such parts exist. Whether those IC's are useful depends on your use-case I guess, I wanted to keep the complexity low (so without external components). You can probably use it quite easily to encrypt and authenticate packets for use in radio communication, it seems...

Sure. Upon looking close at the code I realised I referenced the wrong source of the algorithm I used. The implementation I used was from http://code.google.com/p/curve25519-donna/. You can just include or copy paste the curve25519-donna.c file from that project. Attached is the file I used to...

My first thought was; don't use Matlab. But sometimes you just have to, I was required to use it at uni too. I still have it installed so I gave it a shot; The problem is apparently known; 95024-why-is-my-serial-port-not-recognized-with-matlab-on-linux-or-solaris, it's because Matlab detects...

I started writing a reply for this, but figured out it would be better to make a separate topic on this as it is somewhat off-topic to storing private keys. Please read my post Experiences with encryption on Teensy.

This post started as a reply to the forum post "Teensy as secure storage for private keys", and this remark posted by cr7pt0: I started typing a reply to this but then realized it would probably be better to make a separate post for this instead of hijacking the thread. This is not really a...

In the Netherlands you can actually order on https://nl.farnell.com/, (the normal B2B site) but there are several conditions. You have to order above 50 EUR (ex VAT) and pay in advance through bank transfer. I've used it several times in the past and it worked quite well, perhaps its worth...

You reversed the voltage input. Check the wiring on the breadboard, you connected the Teensy's ground to the red wire of the battery and the Teensy's plus to the ground. The wire colors are correct in your diagram but you placed them in the wrong rows of the breadboard. See the annotated figure...

About a month ago I was experimenting with reading data from an OBD-II bus, ISO 1941-2 to be precise. I have no experience with the chip you are using, but I can point out some alternatives, you have probably come across the MC33290, which seems to be the most commonly used chip in other...

Paul, now that T3.2 is out of the door (great update btw); I'm not sure whether you wanted the results of the beta test through the forum or via email, so I emailed you my results on the 8th, did that email reach you?

You should try Paul's fork of Arduino-IRremote: https://github.com/PaulStoffregen/Arduino-IRremote, the one you link probably doesn't support Teensy 3. (Edit: the download https://www.pjrc.com/teensy/td_libs_IRremote.html should also work, that page also provides some more information.)

Check, I thought you meant the spark caused the noise. I tried it and can confirm that holding the Teensy to the housing and squeezing the lighter does indeed cause the occasional reset / program mode to trigger. The positioning of the Teensy is of the essence, with my lighter it works only on...

Tried it; works well, couldn't get the program mode to trigger with these components in place. I saw some very small dips on the oscilloscope, in the order of millivolts, I guess that's good enough. I'll probably put this fix in place for real next weekend and start testing the device again. I...

Tried this; soldered a wire from 3v3 to the program pin, photo attached for detail: With this wire in place I tried getting the programming mode to trigger with the same test methodology; attached the 70 cm wire to the ground and newly placed wire and placing it over the inverter. I could not...

Okay, I wrongly believed the program pin was also connected to the larger chip on the Teensy LC and did not want to interfere with bootloader chip initiating programming mode. Mea culpa; it is not connected so a pullup would not interfere with its function. I tested with a 10k pullup from the...

To get some information about the duration of the pulses I hooked up my logic analyser today. The pulses are periodic, the first one is consistently around 5 microseconds, the second one around 7 microseconds: While doing these tests I noticed something peculiar today; with the Teensy LC and...

Wrapping the Teensy in RF shielding wouldn't help much, as it is the wire attached to the program pin that's causing the problem. I'd have to shield the entire wire. I tried a low pass filter today, which seemed to work quite well in the test situation. I've used 100 nF and 150 ohm, resistor...

The problem isn't caused by back-emf from the relais. The Teensy that is being tested (in the bottom of the photograph) is not connected to the UPS or it's relays, as said in the post, a wire connected to the program pin and ground pin is placed over the UPS only (not connected to anything).

Hi all, My current project is about modifying an old uninterruptible power supply to something more useful; a portable power supply which charges from 12v and can provide 12v output for a while (timing out after x seconds) when the external power input drops below a thresshold. The idea is to...

Physically you can just make it point upwards... I always solder them at the top side before I put female headers on my Teensies as placing the crystal is harder afterwards (didn't require an RTC yet, so I'm not sure it works). However, thinking about this makes me wonder if the crystal's...

I was just thinking about designing this PCB when I drove back home today. Looks like you beat me to it :D Looks great! I'm happy to hear the idea worked out well.

I recently purchased a Teensy LC and performed the analysis I have also done for the previous versions. Once again, credit for Manitou for figuring out how to do this on the Teensy LC (Your suggestion from #36 looks particularly good on these :) ). Details on the 'how' and the measurement data...

Back when Teensy 3.0 was released we had a discussion about a function which returns the amount of free memory: 23256-Get-Free-Memory-for-Teensy-3-0. Duff and I tried to create a function which did that, but as Stevech and tni explained back then, such a function isn't as trivial as it would...

The mockup is 2.2 by 0.7 inch, OSHPark has a flat fee of 5$ per square inch, that gives you three boards. So somewhere in the order of: ((2.2 * 0.7) * 5$) / 3 = 2.56$ per board? Time will probably have to go into deciding on a pinout for the extension part, and a few prototypes runs are likely...

I'm not going to comment on the last few pages, it has diverted quite a bit from the original topic. A few days ago I had an idea might make the bottom pins more easily accessible; OSHPark seems to support internal cutouts...

Stevech, could you please be a little bit less negative towards libraries - besides RadioHead - which deal with RFM69 radios? The datasheet for RFM69CW details quite a lot additional parameters which you can tune for all modulation parameters. When I wrote my own library for the RFM69 radio...