Why Teensy 3.5 or 3.6

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MichaelMeissner

MichaelMeissner

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Why Teensy 3.5 or 3.6?

The Teensy 3.5/3.6 offers many features over the current Teensy 3.2/LC and I'm wondering what is drawing users towards these new microprocessors. So out of curiousity, what are the features that caused you to pledge on kickstarter (note, it isn't a single choice, it could be multiple things that draw you to the new Teensies):

  • New Shiny: Some people always want to be on the bleeding edge and have the latest cool toys, even if they might not have yet reached the point where the current Teensies can't do what they want;
  • Support PJRC: This forum is the most helpful of any of the electronics forums I have been on, and buying more Teensies keeps PJRC in business;
  • More speed: The 120Mhz/180Mhz clock speed will allow you to do calculations much faster;
  • Hardware single precision floating point: Along with faster cycle times, having hardware floating point will speed up certain programs;
  • More flash memory: The 3.5 has 512K of flash and the 3.6 has 1M of flash compared to 256K of flash on the 3.2, and some programs need a lot of read-only constants or instructions;
  • More SDRAM memory: The 3.5 has 192K of SDRAM (read/write memory) and the 3.6 has 256K of SDRAM compared to the 64K of SDRAM in the 3.2;
  • More EEPROM memory: The 3.5 and 3.6 have 4K of EEPROM compared to the 2K of the 3.2;
  • More DMA channels: The 3.6 (and maybe 3.5) have 32 DMA channels compared to 16 of the 3.2;
  • Hardware random number generator: The new chips have support for returning a hardware random number;
  • hardware crypto instructions: The new chips have new instructions to improve the speed of some cryptography applications;
  • Micro-SD card reader on board: While you can add on a micro-SD card reader to existing Teensies, it is easier if is built-in to the Teensy;
  • Faster micro-SD: The built-in micro-sd card reader should be much faster (on fast cards) than the add-on readers, due to more pins used in parallel and higher SD modes;
  • Secondary USB: The Teensy 3.5/3.6 have provisions for a second USB channel that can act in host mode (and the 3.6 can run at 480 Mbit/second) -- this of course depends on other software being written to work with the secondary USB;
  • More CAN buses: The Teensy 3.6 has 2 CAN buses compared to the 1 in the Teensy 3.2 and Teensy 3.5;
  • More UARTs: The Teensy 3.5/3.6 have 6 UARTs (serial lines) compared to the 3 of the Teensy 3.2;
  • More i2c buses: The Teensy 3.5 has 3 i2c buses and the Teensy 3.6 has 4 i2c buses compared to the 2 in the Teensy 3.2 -- the problem is most of the libraries that use i2c to communicate to specific devices assume there is only one i2c bus;
  • More SPI buses: The Teensy 3.5/3.6 have 3 SPI buses compared to the 1 in the Teensy 3.2 (and 2 in the LC) -- the problem is most of the libraries that use SPI to communicate to specific devices assume there is only one SPI bus;
  • More i2s buses: The Teensy 3.5/3.6 have 2 i2s buses compared to the 1 i2s bus on the Teensy 3.2;
  • More PWM pins: The Teensy 3.5 has 20 and the Teensy 3.6 has 22 PWM pins compared to 12 in the Teensy 3.2;
  • More digital pins: The Teensy 3.5/3.6 has 51 digital pins compared to the 34 pins on the Teensy 3.2 (I may be slightly off in terms of the total pin count);
  • More digital pins on the outer rows: The Teensy 3.5/3.6 have 40 pins on the outer rows for use in breadboards that can be used as digital pins compared to 26 on the Teensy 3.2;
  • More analog input pins: The Teensy 3.5/3.6 have 25 analog input pins compared to 21 on the Teensy 3.2;
  • More analog input pins on the outer rows: The Teensy 3.5/3.6 has 20 analog pins on the outer rows for use in breadboards that can be used as analog input pins compared to 10 on the Teensy 3.2;
  • More DATs: The Teensy 3.5/3.6 have 2 digital->analog output pins compared to 1 on the Teensy 3.2 -- you could use this for stereo output if you don't need the full 16-bit precision that the sound shield offers;
  • More timers: The Teensy 3.5/3.6 have 14 internal timers compared to the 8 on the Teensy 3.2;
  • Ethernet: The Teensy 3.5/3.6 have dedicated pins for ethernet support while on the Teensy 3.2 it is an add-on shield with an older ethernet chip;
  • RTC crystal: The crystal for the RTC is part of the Teensy 3.5/3.6, while on the Teensy 3.2 you have to solder an external crystal.
  • Too much money: Yeah right, but it could be a reason :confused:

Of course there are a few things that might cause you to choose a Teensy 3.2 over the 3.5/3.6:

  • Teensy 3.2 is cheaper (and LC is even cheaper);
  • Teensy 3.2 has 1 more touch pin than the Teensy 3.6 (and the Teensy 3.5 does not support touch pins at all);
  • Teensy 3.2 is 1" shorter than the 3.5/3.6 (the extra pins/micro sd card reader do take up more space);
  • You are using a shield/carrier/whatever designed for the Teensy 3.2 that knows about the back row of pins;
  • The Teensy 3.2 is 5 volt tolerant on the digital pins and the 3.6 is not 5 volt tolerant (but the 3.5 is 5 volt tolerant);
  • You don't want to upgrade your Teensydunio software. :confused:
  • Your Teensy 3.0 from the original kickstarter campaign is still serving you well and you don't need to get anything else.

:cool:
 
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Great summary, Michael.
I have a small addition:


  • Even with same MHz, the Teensy 3.6 is faster, because it has 8 KB Cache.
 
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I for myself would narrow my motivation to
MichaelMeissner said:
  • Support PJRC: This forum is the most helpful of any of the electronics forums I have been on, and buying more Teensies keeps PJRC in business;
  • More speed: The 120Mhz/180Mhz clock speed will allow you to do calculations much faster;
  • Hardware single precision floating point: Along with faster cycle times, having hardware floating point will speed up certain programs;
  • More flash memory: The 3.5 has 512K of flash and the 3.6 has 1M of flash compared to 256K of flash on the 3.2, and some programs need a lot of read-only constants or instructions;
  • More SDRAM memory: The 3.5 has 192K of SDRAM (read/write memory) and the 3.6 has 256K of SDRAM compared to the 64K of SDRAM in the 3.2;
    ...
  • Micro-SD card reader on board: While you can add on a micro-SD card reader to existing Teensies, it is easier if is built-in to the Teensy;
  • Faster micro-SD: The built-in micro-sd card reader should be much faster (on fast cards) than the add-on readers, due to more pins used in parallel and higher SD modes;
  • Secondary USB: The Teensy 3.5/3.6 have provisions for a second USB channel that can act in host mode (and the 3.6 can run at 480 Mbit/second) -- this of course depends on other software being written to work with the secondary USB;
    ...
  • Ethernet: The Teensy 3.5/3.6 have dedicated pins for ethernet support while on the Teensy 3.2 it is an add-on shield with an older ethernet chip;
  • RTC crystal: The crystal for the RTC is part of the Teensy 3.5/3.6, while on the Teensy 3.2 you have to solder an external crystal.
Click to expand...

Note, I could not find an I2S1 but only I2S0:
  • ??More i2s buses: The Teensy 3.5/3.6 have 2 i2s buses compared to the 1 i2s bus on the Teensy 3.2; ??
 
WMXZ said:
Note, I could not find an I2S1 but only I2S0:
  • ??More i2s buses: The Teensy 3.5/3.6 have 2 i2s buses compared to the 1 i2s bus on the Teensy 3.2; ??
Click to expand...

My notes are the 2nd i2s bus transmitter could be on pins 15/A1 or 26 and the receiver could be on pins 38/A19 or 28. I believe the 3 clocks (MCLK, BCLK, LRCLK) must be the same. That being said, I don't know anything about i2s, other than what I've read in other posts.
 
MichaelMeissner said:
  • Support PJRC: This forum is the most helpful of any of the electronics forums I have been on, and buying more Teensies keeps PJRC in business;
  • More speed: The 120Mhz/180Mhz clock speed will allow you to do calculations much faster;
  • More flash memory: The 3.5 has 512K of flash and the 3.6 has 1M of flash compared to 256K of flash on the 3.2, and some programs need a lot of read-only constants or instructions;
  • More SDRAM memory: The 3.5 has 192K of SDRAM (read/write memory) and the 3.6 has 256K of SDRAM compared to the 64K of SDRAM in the 3.2;
  • More EEPROM memory: The 3.5 and 3.6 have 4K of EEPROM compared to the 2K of the 3.2;
  • Micro-SD card reader on board: While you can add on a micro-SD card reader to existing Teensies, it is easier if is built-in to the Teensy;
  • Secondary USB: The Teensy 3.5/3.6 have provisions for a second USB channel that can act in host mode (and the 3.6 can run at 480 Mbit/second) -- this of course depends on other software being written to work with the secondary USB;
  • More digital pins on the outer rows: The Teensy 3.5/3.6 have 40 pins on the outer rows for use in breadboards that can be used as digital pins compared to 26 on the Teensy 3.2;
  • More timers: The Teensy 3.5/3.6 have 14 internal timers compared to the 8 on the Teensy 3.2;
  • Ethernet: The Teensy 3.5/3.6 have dedicated pins for ethernet support while on the Teensy 3.2 it is an add-on shield with an older ethernet chip;
  • RTC crystal: The crystal for the RTC is part of the Teensy 3.5/3.6, while on the Teensy 3.2 you have to solder an external crystal.
Click to expand...

For the other features I cannot foresee a need for or haven't figured out how to use yet (ex: DMA). It doesn't hurt that they are there though. Getting access a beta board early influenced what Kickstater tier I selected. My primary interest is in the 3.6. The 3.5s are destined to be used in test fixtures and one off projects
 
MichaelMeissner said:
My notes are the 2nd i2s bus transmitter could be on pins 15/A1 or 26 and the receiver could be on pins 38/A19 or 28. I believe the 3 clocks (MCLK, BCLK, LRCLK) must be the same.
Click to expand...

This dual stereo I2S feature is common to Teensy 3.1, 3.2, 3.5 and 3.6.

Teensy 3.0 had only a single stereo channel.
 
None of the above are bad things - except perhaps for it being 'less Teensy' and $5-10 more for the added features. Based on RAM/EEPROM/SPEED:: For the similar cost one could expect to do much more with two T_3.6's than even three T_3.2's, or at OSH pricing on the T_3.2, one each T_3.5 and T_3.6.

Most of the first half are real wins for the increased performance and capabilities which is why I ordered more than a few to play with, that and the second one :: Support PJRC

New Shiny
Support PJRC
More speed
Hardware single precision floating point
More flash memory
More SDRAM memory
More EEPROM memory
More DMA channels
Hardware random number generator
hardware crypto instructions
Micro-SD card reader on board
Faster micro-SD
Secondary USB
New Shiny
Support PJRC

MM: The KS page on T_3.5 shows: 16 General Purpose DMA Channels
 
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My interest in it was being able to scale. Have assorted projects, some of which turn out to need to go up (or in some cases down) once code starts coming together and like having the option to slide price/performance on the same libraries without having. A 3.6 lets me do things that previously I'd have assumed needed a Pi-ish device that I can now start on a Teensy 'and see what happens'.

Still suspecting most of the things I personally do will actually end up in a 3.2, but knowing that if I get into a corner I can throw a small amount of $ at the problem and just keep going on the fun stuff is a really nice option when my hobby is constrained by time.
 
For me the list is:

• Support PJRC: This forum is the most helpful of any of the electronics forums I have been on, and buying more Teensies keeps PJRC in business;
• More speed: The 120Mhz/180Mhz clock speed will allow you to do calculations much faster;
• More flash memory: The 3.5 has 512K of flash and the 3.6 has 1M of flash compared to 256K of flash on the 3.2, and some programs need a lot of read-only constants or instructions;
• More SDRAM memory: The 3.5 has 192K of SDRAM (read/write memory) and the 3.6 has 256K of SDRAM compared to the 64K of SDRAM in the 3.2;
• Micro-SD card reader on board: While you can add on a micro-SD card reader to existing Teensies, it is easier if is built-in to the Teensy;
• Faster micro-SD: The built-in micro-sd card reader should be much faster (on fast cards) than the add-on readers, due to more pins used in parallel and higher SD modes;
• Ethernet: The Teensy 3.5/3.6 have dedicated pins for ethernet support while on the Teensy 3.2 it is an add-on shield with an older ethernet chip;

I actually didn't realize that the 3.6 is not 5v Tolerant on digital pins. I'll have to check my projects on that one...
 
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Paul does not call out the hardware debug pin pads on the K66/K64 bottom on KS ( except in comments ) - that might make a good KS Update paragraph or two.

@MM - Those exposed hardware DEBUG pins combined with the backward compatibility to T_3.2 means even if you wanted to use T_3.2 in the end - prototyping and debugging on the K66/K64 would provide extra room/horsepower for debugging overhead. Not just hardware debugging but it could include copious debug spew and debug messages (and lights/switches) on the faster MCU with larger RAM/FLASH space going out "spare" Serial/SPI/I2C ports leaving uncompromised the end use ports while debugging/developing. Then any #ifdef debug_only code would go away and it would fit and run as expected on a T_3.2. This prototype phase could include easier hardware use on the bench given that the old T_3.2 under pads are brought to edge pins. In the early stages before a custom PCB was made or final hardware was chosen it could be wired to the exposed edge pins.
 
defragster said:
... might make a good KS Update paragraph or two.
Click to expand...

My main goal with Kickstarter communication is setting reasonable expectations for the product. I'd prefer to leave this for a future update when there's actually a way to make use if it from Arduino.
 
A bit early indeed without a general robust solution to over hype - also a bit late to make a splash on the KS. You made a note on the forum - but even MM forgot it as a key element so many have asked for that could be a reason to choose these new models. Would those looking for professional solutions be able to buy a debug hardware unit with usable software today? I suspect so given that others have posted hacked solution for current models, unless those tools wouldn't work with the Arduino toolchain to get good results. The closest I've gotten to regular usage was in Visual Studio getting to see local vars and set breakpoints - the system I worked on had a real debugger and needed it - but the code I wrote was higher level and the best help I got was multi-mon to tame debug spew and view/edit the code as I went, but it wasn't timing critical or resource limited. As noted in P#13 these new Teensy's will have more resources to support what I'm used to, certainly as an emulator for a T_3.2.

It wouldn't take a big paragraph to tell me more than I know about what to expect from it. What I know of Hardware debuggers would be most useful at/after a crash to see the state of the machine - but you have to know enough to examine the pieces and where to find them to learn what is not as you expected it that got you there.
 
For me all of the above. But the most important ones are:
  • New Shiny: Some people always want to be on the bleeding edge and have the latest cool toys, even if they might not have yet reached the point where the current Teensies can't do what they want;
  • Support PJRC: This forum is the most helpful of any of the electronics forums I have been on, and buying more Teensies keeps PJRC in business;
  • More speed: The 120Mhz/180Mhz clock speed will allow you to do calculations much faster;
  • Hardware single precision floating point: Along with faster cycle times, having hardware floating point will speed up certain programs;
  • More UARTs: The Teensy 3.5/3.6 have 6 UARTs (serial lines) compared to the 3 of the Teensy 3.2;
  • More i2c buses: The Teensy 3.5 has 3 i2c buses and the Teensy 3.6 has 4 i2c buses compared to the 2 in the Teensy 3.2 -- the problem is most of the libraries that use i2c to communicate to specific devices assume there is only one i2c bus;
  • More SPI buses: The Teensy 3.5/3.6 have 3 SPI buses compared to the 1 in the Teensy 3.2 (and 2 in the LC) -- the problem is most of the libraries that use SPI to communicate to specific devices assume there is only one SPI bus;
  • More digital pins on the outer rows: The Teensy 3.5/3.6 have 40 pins on the outer rows for use in breadboards that can be used as digital pins compared to 26 on the Teensy 3.2;
  • More analog input pins on the outer rows: The Teensy 3.5/3.6 has 20 analog pins on the outer rows for use in breadboards that can be used as analog input pins compared to 10 on the
But really for me, who is mostly retired and doing this for fun, probably the two most important are:

New Shiny - It forces me to have to try to learn something new. While doing so it also helps me better understand the other boards as well. Example: while learning about the capabilities of the UARTs and questions about supporting two stop bits, while figuring that out, I also noticed the the Teensy LC could support it as well.

Support PJRC - Both in purchasing some of the new boards, but also in testing things and hopefully making some small contributions to the code base and community.
 
I picked up the 3.5 and 3.6 to tinker with. I'm eager to get playing with the 3.6's features!

I've always used devices that are 5v tolerant though. Even when using a 3.3v device I've found I2C and UART communication will work with a 5v device without using a logic level converter (though I know it is good practice to use one).
With the Teency 3.6 not being 5v tolerant, does that mean that hooking up I2C SDA and SCL lines from a 5V device to the 3.6's I2C bus will damage it?
 
I would imagine the answer is yes, it may be damaged. I think I recall some people frying their LC or Teensy 3.0 with 5v inputs (neither of those are 5v tolerant).
 
For me, it's all about processor capability/speed. I am creating an extension to the audio library for real-time DSP, for use in educational and engineering/scientific labs, to allow the rapid prototyping and deployment of instrumentation and processors. While the 3.2 has been a great unit to get my project off the ground, I'm looking forward to the 3.6 with its floating point, extra memory, faster processor, etc to allow more complex algorithms to be included in the library.
The downside is the need to redesign/build my prototyping carrier board, and to be extra careful of the 5v intolerance! (I "slightly broke" several Arduino Dues with accidental wrong levels before switching to the Teensy 3.2) ;)
 
#1 Uarts (I recently finished a prototype board for a teensy 3.1 and put a 4/1 mux to expand the uarts).
#2 Onboard SD reader (my proto board has an SD card on the SPI lines)
#3 2nd USB (if this can read a thumb drive, it will save one of my uarts)
#4 Memory (I'll be able to parse a file without having to page the data in)
Looks like I'm respinning my proto board for the 3.6
 
[*] Support PJRC: This forum is the most helpful of any of the electronics forums I have been on, and buying more Teensies keeps PJRC in business!

I want to support him, the boards & code work! I've met Paul @ Bay Area Maker Faire & Hackaday conference. Nothing I do is bleeding edge. Over time I've got a couple LC & 3.1 boards. Now we are building a prototype project @ work that contains multiple units (RS-485)!

Dave
 
Is there any planned activity for interfacing to an Arducam or one of the OV76xx cameras to a V3.6?

PS
Not necessarily by Paul but by anyone else.
 
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NuCPU_front_x.jpgNuCPU_back_x.jpgTeensy3_6_x.jpg

Why did I jump on the Kickstarter to get an early T3.6? Because every I/O pin on my T3.2 is connected to something, and I still have more somethings!
 
I don't remember exactly why I'm in :)
But it must have been these reasons:

  • New Shiny: Some people always want to be on the bleeding edge and have the latest cool toys, even if they might not have yet reached the point where the current Teensies can't do what they want;
    Yeah sure!

  • Support PJRC: This forum is the most helpful of any of the electronics forums I have been on, and buying more Teensies keeps PJRC in business;
    Absolutely!

  • More speed: The 120Mhz/180Mhz clock speed will allow you to do calculations much faster;
  • More flash memory, More SDRAM memory, More EEPROM memory

    Yes! More power, more memory, more everything please!
    Although Teensy 2.0 (with AVR) would do for most of my projects :)
    But for some it don't. Especially for high quality audio projects. With 3.6 anything is possible! Or at least most of the stuff I'm trying to build.

  • Faster micro-SD: The built-in micro-sd card reader should be much faster (on fast cards) than the add-on readers, due to more pins used in parallel and higher SD modes;

  • Secondary USB: The Teensy 3.5/3.6 have provisions for a second USB channel that can act in host mode (and the 3.6 can run at 480 Mbit/second) -- this of course depends on other software being written to work with the secondary USB;
    USB host on the 3.6 is definitely one of the reasons.


I'll continue using Teensy 3.2 (or even 2.0) for many of my projects because:

  • Teensy 3.2 is cheaper (and LC is even cheaper);
  • Teensy 3.2 is 1" shorter than the 3.5/3.6 (the extra pins/micro sd card reader do take up more space);
 
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