The Teensy 4.1 from PJRC is now in stock and ready to ship from Envistia Mall.
Teensy 4.1 features an ARM Cortex-M7 processor at 600 MHz. Actual size is 2.4 by 0.7 inch, same form-factor as Teensy 3.6. It uses the same processor as Teensy 4.0, but provides greater I/O capability, including an ethernet PHY, SD card socket, and USB host port. Teensy 4.1 also comes with 4X larger flash memory, and has 2 locations to optionally add more memory.
Not every project requires so much I/O or extra memory. Teensy 4.0 fills those needs. But when you do need more I/O, more memory, fast Ethernet, or connecting USB devices or fast SD card access, the larger Teensy 4.1 brings this extra I/O capability to a platform designed for real-time use with fast 600 MHz M7 performance.
For more details on the Teensy 4.1, see "Teensy 4.1 Released" on the PJRC website.