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Thank you all especially joe and Michael, super useful info and what a great spreadsheet! I'm sorry I didn't put all the code up - I didn't think the rest would benefit, though it's all already open source here if you want a more complete review...

Hi all, we're trying to pull in some code written for Teensy 3.2 to 4.0. Honestly I'm not sure if it's going to work given the time I have. Question 1: I looked around a bit, but wondering if anyone was maintaining a list of the areas most likely to have issues / failures when porting...

Hi folks, just wanted to close those out so the mystery is solved. It's something stupid of course. I had an old version of teensyduino (1.20 rather than 1.27) which fixed it all up. Stupid me, sorry but perhaps it'll help someone else in the future. Should have checked that earlier. Greg

I can confirm udev rules are installed. I've used this computer extensively with teensy 3.0 and 3.1, that's why it's so perplexing. I have the most recent version of teensyduino, and have tested on 1.0.6 as well as 1.6.7 (fresh install), same response. In addition, we get the same response on...

Here's the output from syslog as Paul suggested. You can see in the first set, when the device is plugged in without programming or restarting, teensy is detected correctly. After pressing program button, it no longer detects it as a Teensy. Feb 11 17:23:04 greg-Gazelle-Pro avahi-daemon[735]...

AWESOME - I'm embarrassed I didn't see that. Thank you for the help :)

We're interested in putting the ARM chip from the current version of the Teensy 3.1 on our own board (project is www.photosynq.org, the device is called the MultispeQ), but use Paul's bootloader. I was under the impression taht we could buy this from PJRC but wasn't sure how or where. We've...

A little off topic, but we have a chrome app (javascript) which we use to communicate with a device we built on top of the Teensy (the MultispeQ... the project is called PhotosynQ and can be found at www.photosynq.org). We are suggesting that advanced users, who may need to update the firmware...

Hey guys, I am looking to use the Duff's library in a slightly different way and am seeking some feedback. We are taking analog_reads on a detector, using the 16 bit pins (I think A10 and A11). There's a good amount of noise in the ADC itself, and while we've tracked some of it down there's...

First, background: we are using the Teensy 3.1 to build a handheld spectroscopic device for measuring plant health (www.photosynq.org). We have slowly troubleshot connection with Windows, and finally we have a pretty consistent method for connecting to the device: First, you have to have the...

JBeale - we definitely read that through before we started, that was really helpful. We were hoping perhaps there were other workarounds. stevech - Not really. If it was true 16 bit, our signal would look great even with only 2000 points of resolution. We are considering addressing this by...

Thanks whollender and pkourany - it sounds like the 12/13 bit actual resolution is somewhat of a hard limit mostly determined by noise within the chip itself. I was hoping that some new crazy ideas would emerge, or perhaps something had changed for 3.1, but not yet! We have a pretty well...

We have addressed power supply (we use a Lithium battery with very low internal impedance) - the photodiode is on a circuit board so there's no cables. Light levels are fairly high, but the signal itself is small (on top of the otherwise high light level)... we have simple optics in there now...

We are trying to chase down some noise on a pin photodiode detector we're using to measure IR fluorescence in plants. We recently made some hardware changes to the photodiode to dramatically reduce then noise entering into the system there, but now we've found that the remaining noise is coming...

Hey, haven't posted in a while but just wanted to say that we've finally got a working prototype. It has a CO2 sensor, temp, humidity, light meter with light temperature, and the ability to measure fluorescence and photosynthetic efficiency. We're going to be at the Open Hardware Summit on...

Thanks for the explanation - it actually really helps to understand the history! It's ok - fix wasn't too bad. I switched all atime_t to time_t, but I also had to do change setSyncProvider(Teensy3Clock.get); to setSyncProvider((getExternalTime) Teensy3Clock.get); (see code at bottom for...

I recently setup the Arduino IDE v 1.0.5 along with the newest version of Teensyduino downloaded from PJRC in Ubuntu 12.04. My program (in fact, many versions of the program) which had compiled just fine (also in Ubuntu 12.04) before now gives me the following error: Combined:78: error...

Hmmm... Interval timer does not yet have all the functionality that PITimer does, like setting the period and frequency of the timer... do you know when that might be added, or am I missing something?

Definitely - let me get some cooler pictures first - I should have them by early next week. Actually, we run our bioreactors on the Teensy 2.0++ so I'll snap some pictures of those too! Thanks for the explanation - I'll switch over to intervaltimer. Thanksfully, linuxgeek already gave me a...

Awesome - just got a chance to look at it... and I'm confused about one thing - loglow produced two different libraries for timers, one is PITimer and the other is IntervalTimer... is there a difference? IntervalTimer says it's based on PITimer but I can't tell that it added or changed...

So I was having some issues recreating the signal processing board that Robert had made, so it was taking me a few days just to get the unit back up and running. But I finally did, and the signal looks great! Actually, as you suggested, one of the biggest improvements came from moving to a...

Yes, I've done that but it only helped some. I have comparisons between the benchtop unit (called the Ideaspec) and the Teensy-based unit, and it's a very big different quality-wise even with the internal analog reference. Some of the noise I can get rid of, for example, by just turning off...

Sorry it's taken me a while to respond, I must have missed the last few comments in my inbox: duff - an RTOS is probably the most efficient solution for high speed, but I think it takes a lot away from the usability and modability of the system by "regular" users. Ideally, we would like anyone...

Ok - we made some progress. Now I've got code which: 1) takes analogread()s pretty fast (by setting analogreadaveraging to 1 as suggested) - it takes only a few us per read. 2) can save data to the SD card - each write or append takes about 20ish us (actually, when you do file.print(O_WRITE)...

I'm trying to get Dave, the professor here, to effectively describe what we're doing on the website, he'll do it much better than me of explaining it (hopefully that'll be the next blogpost on photosynq) - maybe he'll even just jump on this forum and respond directly. In the mean time, these...

Thanks Constantin and adrianfreed. I'll give that a read and see if I can figure it out. Ideally, in the long run, we'd like samples as fast with as accurate timing as possible. Basically, the faster and more accurate the timing the more interesting science we can do. For the moment to get...

Phew - sorry it took a few days to respond, been trying to work on this to get some worthwhile numbers to share. Thanks linuxgeek! In our group we have some good expertise but not a lot on the arduino coding side of things, so I'd really love help and ideas on how to make things...

Update: Definitely turning off the averaging made the biggest difference - that gets the speed down to 3us from the standard 20us for a single analog read! Also, my labmate Chris developed a neat little trick for actually identifying when the analogread() was pulling the sample: Pull one...

Hello! Me and some other folks are working making a hand-held, open source device which can measure plant photosynthesis. This device will ultimately connect to a cell phone to allow for easy display of results and to transfer the data into a global database of plant information sharing. The...

I am working on a project which sampling a measurement frequently - at the slowest we need to sample every 5us. I've tested the ADC using analogread() on the Teensy 3.0 and have found it takes 20 - 23us to read an analog signal, which is just a bit too slow for our application. I've read...

Hey guys, I had a similar issue with the Serial Monitor not displaying things that I was printing (using teensy 3.0 with Arduino 1.0.3 downloaded from PJRC). I read through a lot of forum discussion and tried many things (using Uart.print instead of Serial.print, trying serial2 or serial3...