The FortyTwo Systems MEGA, a SAM C21N-Based Arduino Mega Successor, Lands with Its Arduino Core
Arduino Mega replacement offers pin compatibility and support for the Arduino IDE and PlatformIO, but with considerably more power.
Dave Cutting's shot at offering more power to those building in the Arduino Mega ecosystem, the Microchip SAM C21N-based FortyTwo Systems MEGA, is now available to buy, just over a year since the first prototype landed.
"This board breaks out the SAM C21N microcontroller into a board that is a drop-in replacement for the Arduino Mega," Cutting explained four months ago, while showing off a functional late-stage prototype. "The SAMC line of microcontrollers from Atmel (now Microchip) open up a world of possibilities because they run at 5V and have on-board CAN controllers. Break free from the size and processing power limitations of the original Arduino MEGA with a 32-bit Arm core."
That prototype, though, wasn't quite ready for prime-time. "I accidentally crossed the SWCLK and SWDIO lines on the JTAG SWD header," Cutting admitted. "With some custom cable magic that flaw was easily fixed, and I'll correct the problem in the next revision." There was also the work of writing an Arduino core which would bring support for the SAM C21N to the Arduino IDE, allowing for a quick switch for code written for the original Arduino Mega.
Now, the FortyTwo Systems MEGA is complete — and that little JTAG bug has been fixed. "It runs at 5 volts, features advanced communication peripherals, and has many times more flash and RAM compared to the Arduino Mega," Cutting explains. "It also runs much faster and provides much more processing power. It is a drop-in replacement for the Arduino MEGA. Additionally, it has dual CAN controllers so you can interface it to industrial devices."
As with the earlier prototype, the board is built around a Microchip SAMC21N18A with a single Cortex-M0+ core running at 48MHz, 32kB of RAM, and 256kB of flash, there are two CAN-FD controllers, 8 SERCOM instances which can each be configured as SPI, I2C, or UART, 12 pins connected to dual 12-bit analog to digital converters (ADCs), and one 10-bit digital-to-analog converter (DAC). The Arduino core, meanwhile, is complete bar final testing, while the underlying toolchain has been fully tested. There's even support for the board in PlatformIO, though Cutting admits "this still needs some clean-up."
The FortyTwo Systems MEGA is now available on Tindie at $42, with the design files available on GitHub under the reciprocal GNU General Public License 3.