Wiki Coming - Please link worthy posts

{ reminder:: link instructive things you see or do on the forum here so when the WiKi gets rolling stuff can be pulled out and covered }

Teensy 3.2 Interrupts to Blink LED's at Different Rates :: systick_isr() timer interrupt

Link to the Newlib Library Documentation: Teensy uses:: Newlib is a C library intended for use on embedded systems.

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Teensy 3.6 Analog Reference Card showing pin source:

Generate an assembler listing when compiling Teensy

Tutorial on State machine usage - don't use delay() - watch the clock! Part 1 of 3 multi-tasking-the-arduino-part-1/all-together-now

Teensy Specific LED/DIGITAL FLASHER class sample with elapsedMicros and no delay()

Using a local DEF file to alter compile time settings [FrankB :cool:]::

ARM MEMORY access cycles: for RAM / FLASH / EEPROM / PORTS
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Teensy 3.6 startup problems with some power supplys - or - Teensy resets due to EMI on its reset line.

- Add a capacitor ~10nF..~22nF between RESET an GND.
"Also to note that on my Windows 7 machine, it's recognized as "Teensy" while on my Windows 10 machine it's only recognized as "COM5".
At least that part is normal.

With Windows 10, Microsoft finally began shipping a system INF to cause their own USBSER.SYS driver to load for serial devices.

Before Windows 10, everyone using standard serial (technically usb communication class abstract control model - one of many standard officially published by the usb organization) had to provide their own INF. Usually this is called a "driver", even though it's merely an INF that tells Windows XP, Vista, 7, 8 to load their own USBSER.SYS driver. The INF PJRC provides has "Teensy" in its description, so when you see the device appear in the Windows Device Manager, it says Teensy.

On Windows 10, the name which appears is the generic name Microsoft put into their own INF. So it's perfectly normal to see this difference between Windows 10 and older versions of Windows.
It's on the to do list, unfortunately it keeps getting pushed lower down in priority as things like Teensy 3.5, Teensy 3.6, and USB Host development get pushed up in priority. We have been working on some IT infrastructure changes that will help facilitate the creation of the Wiki. I commit to any timeline for this, but I can assure you that it has not been forgotten about.
... I've seen notes that predate mine. What I've seen and noted about the WiKi is - they 'write themselves' - like this thread - and the forum - they just need an outlet.

Definition of wiki
:* a website that allows visitors to make changes, contributions, or corrections
Ability to debug is key to develop quality applications. I can't see how this is surpassed by other priority items.
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Here's some info about connecting more than 32 Teensy boards to a PC, shared by email from someone who wishes to remain anonymous.

Apparently the Linux /dev/ttyACM driver has a limit of "only" 32 simultaneous devices. Apple's driver on Sierra has a limit of only 16. So far, no info about whether Windows has a similar limit.

The info for Linux:

So I got 64 teensies to mount on opensuse 13.2
in /usr/src/linux/drivers/usb/class/cdc-acm.h
there is a
#define ACM_TTY_MINORS 32

set that to 64 or 128. I did 256

then borrowing heavily from

cd /usr/src/linux
make clean
make oldconfig
cp /usr/src/linux-obj/HW/NAME/Module.symvers /usr/src/linux/
make scripts
make prepare
cd /usr/src/linux/drivers/usb/class
make -C /usr/src/linux SUBDIRS=$PWD modules
cp /usr/src/linux/drivers/usb/class/cdc-acm.ko /lib/modules/VERS/kernel/drivers/usb/class/
shutdown -r now

Edit: Windows 10 was tested and found to support only 16 simultaneous devices.
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It has been said before, but just to link this into the page for eventual inclusion into a wiki. The Teensy 3.5 and 3.6's bootloader has a mode to wipe out the memory. You have to press and keep pressed, the program button for 13-17 seconds:

The program wipe feature is not 20+ seconds. It's *exactly* 15 seconds. The bootloader actually looks for a press that lasts between 13 to 17 seconds, so you're allowed +/- 2 seconds. If you hold for 20 seconds or more, you'll miss that window.

Whether or not this program wipe will help is anyone's guess. Seems very likely the hardware may just be damaged. But to even try the program wipe, you really need to look at a stopwatch or clock with seconds when pressing the button, so you can hit that 13 to 17 second window.

This is from: