Forum Rule: Always post complete source code & details to reproduce any issue!
Results 1 to 5 of 5

Thread: MegaDUE breakout for Teensy 3.6 - Schematic - WANTED for use with Teensy 4.1

  1. #1
    Junior Member
    Join Date
    Feb 2021
    Posts
    2

    MegaDUE breakout for Teensy 3.6 - Schematic - WANTED for use with Teensy 4.1

    I intend to use Teensy 4.1 with https://www.pjrc.com/megadue-shield-breakout-board/
    I found Schematic for Teensy 4.1 on the end of page https://www.pjrc.com/store/teensy41.html
    Also I found Schematic for Teensy 3.6 and also front and back side and pinout for both.
    On first look only pins 40 and 41 are different beetween 4.1 and 3.6. which is not use for anything.
    It is not connected to GND or Vcc.
    To be sure to put T4.1 in megadue breakout I need Schematic for it (to avoid smoke!)
    I can not found it, only pinout and front or back side pdf.
    Use that info I think it is safe to put T4.1 in megadue break out.
    But schematic for megadue breakout or confirmation from someone will be nice.

    If it work it will be the most powerfull MCU on the world for real time operation.

    Thanks

  2. #2
    Junior Member
    Join Date
    Feb 2021
    Posts
    3
    Quote Originally Posted by zlatkoh1 View Post
    I intend to use Teensy 4.1 with https://www.pjrc.com/megadue-shield-breakout-board/
    I found Schematic for Teensy 4.1 on the end of page https://www.pjrc.com/store/teensy41.html
    Also I found Schematic for Teensy 3.6 and also front and back side and pinout for both.
    On first look only pins 40 and 41 are different beetween 4.1 and 3.6. which is not use for anything.
    It is not connected to GND or Vcc.
    To be sure to put T4.1 in megadue breakout I need Schematic for it (to avoid smoke!)
    I can not found it, only pinout and front or back side pdf.
    Use that info I think it is safe to put T4.1 in megadue break out.
    But schematic for megadue breakout or confirmation from someone will be nice.

    If it work it will be the most powerfull MCU on the world for real time operation.

    Thanks
    Cool!
    never seen Schematic for T4.1

  3. #3
    Senior Member+ MichaelMeissner's Avatar
    Join Date
    Nov 2012
    Location
    Ayer Massachussetts
    Posts
    4,035

    Cool

    Note the pins in the Teensy 4.1 are different than the Teensy 3.5/3.6. Whether this matters depends on what pins are used by the code.

    Off the top of my head some of the differences include:
    • The Teensy 4.1 does not have 3 of the 4 inside pins on the right side (i.e. it has VIN, but it does not have A10, A11, and AREF);
    • The Teensy 4.1 does not have the 24 pads that the Teensy 3.5/3.6 has underneath the PCB. It has different pins laid out in a different fashion;
    • The Teensy 4.1 does not have the 2 DAC pins (digital to analog converters) for moderate quality sound output that the Teensy 3.5/3.6 has;
    • The analog pins above A9 are laid out differently;
    • Only the first serial port (Serial1) is common between the two. Pins 7-8 are Serial2 on Teensy 4.1 and Serial3 on the Teensy 3.5/3.6. The other serial ports are on other pins;
    • The first I2C bus (pins 18-19) is common between the two. The other I2C buses are on other pins.
    • The first SPI bus (pins 11-13) are common between the two. The other SPI buses are on other pins. The Teensy 3.5/3.6 has alternate pins for the first SPI bus, but the Teensy 4.1 does not have these alternates. These alternates are often used for I2S sound input/output on the Teensy 3.x because I2S uses some of the default SPI pins; (and)
    • The I2S pins are completely different between the Teensy 4.1 and 3.5/3.6.

  4. #4
    Junior Member
    Join Date
    Feb 2021
    Posts
    2
    Thank you very much for the quick and very extensive response. The main functions of SPI and I2C are in the same place. The fact that some pins are missing is not so important and it does not really matter that they are mixed. In addition to SPI and I2C I will only use 1 more wire and https://www.buydisplay.com/serial-sp...ra8876-for-due that uses SPI or I2C and more RESET, INTERRUPT, WAIT, means 3 more free GPIOs. I need one GPIO for 1-wire and on teensy 4.0 I would miss GPIO. It is important to me that the Teensy 4.1 can fit nicely into the tray and that it has its own base and not that I put it in the breadboard. I was afraid that some pins didn’t have a specific role so they were connected to Vcc, GND or PullUp and on another Teensy was the other way around. It is important that when you put T4.1 that there is no smoke. And you described all the differences so nicely that you probably have the scheme megadue_breakout so please send it to me.

  5. #5
    Senior Member+ MichaelMeissner's Avatar
    Join Date
    Nov 2012
    Location
    Ayer Massachussetts
    Posts
    4,035
    Quote Originally Posted by zlatkoh1 View Post
    Thank you very much for the quick and very extensive response. The main functions of SPI and I2C are in the same place. The fact that some pins are missing is not so important and it does not really matter that they are mixed. In addition to SPI and I2C I will only use 1 more wire and https://www.buydisplay.com/serial-sp...ra8876-for-due that uses SPI or I2C and more RESET, INTERRUPT, WAIT, means 3 more free GPIOs. I need one GPIO for 1-wire and on teensy 4.0 I would miss GPIO. It is important to me that the Teensy 4.1 can fit nicely into the tray and that it has its own base and not that I put it in the breadboard. I was afraid that some pins didn’t have a specific role so they were connected to Vcc, GND or PullUp and on another Teensy was the other way around. It is important that when you put T4.1 that there is no smoke. And you described all the differences so nicely that you probably have the scheme megadue_breakout so please send it to me.
    I don't have anything to do with megadue (whatever that is). I just maintain a spreadsheet that compares the pins on each Teensy, so I know what the differences are:

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •