The stock levels of Raspberry Pi are slowly returning to normal, and it is hoped that by the end of 2023, things should be back to pre-pandemic, pre-chip shortage norms. But the "gap" left by Raspberry Pi has seen other board makers rush to offer alternatives, and the $33 BigTreeTech BTT Pi v1.2 looks like a low-cost SBC for makers and 3D printer fans.
BTT Pi v1.2 is an SBC, and it can be used as a Raspberry Pi replacement on par with the Raspberry Pi 3 Model B. At the heart of BTT Pi v1.2 is the Allwinner H616 SoC, which features a quad core Arm Cortex A53 running at 1.5GHz. BTT Pi v1.2's CPU clock is 300MHz higher than its direct competitor, the Raspberry Pi 3 B. The Raspberry Pi Zero 2 W also uses the same 64-bit Arm Cortex A53 CPU, clocked at 1GHz and with only half the RAM.
The 40-pin GPIO is color-coded and, from a casual glance, the pinout looks to be flipped 180 degrees, along with the rest of the board. That will make pretty much all Raspberry Pi cases incompatible with BTT Pi v1.2. How the GPIO can be used is a mystery for now. Looking in the support section of BigTreeTech's website we cannot find a guide on accessing the GPIO via any programming language. At a guess, we would assume that the GPIO can be accessed via the Linux OS, in a similar manner as to how Khadas VIM boards can. Can you use a Raspberry Pi HAT on the board? Again this depends on the GPIO pinout and software compatibility.
So why has BigTreeTech released the BTT Pi v1.2? Well, it all boils down to 3D printing. BTT Pi v1.2 is designed for bringing extra features to even the best 3D printers. BTT Pi v1.2 features support for Klipper, an alternative firmware for 3D printers that requires a little more processing power than G-Code. You'll still need your own 3D printer mainboard, but adding BTT Pi v1.2 and an ADXL345 accelerometer (via the dedicated port) will enable the use of Klipper's input shaping tool. Klipper can greatly increase the speed of your 3D printer, but all that high-speed and heavy print heads mean inertia, and that can manifest itself as ghosting / ringing. Input shaping (resonance compensation) reduces these issues by attempting to cancel out the resonance, and this is where the accelerometer comes in handy. BTT Pi v1.2 also provides a means of cloud printing via the Cloud 3D Print app.
BigTreeTech BTT Pi V1.2 is currently for sale, priced at around $33.
