machine learning

55 TOPS Raspberry Pi AI PC - 4 TPUs, 2 NPUs

I'm in full-on procrastination mode with Open Sauce coming up in 10 days and a project I haven't started on for it, so I decided to try building the stable AI PC with all the AI accelerator chips I own:

  • Hailo-8 (26 TOPS)
  • Hailo-8L (13 TOPS)
  • 2x Coral Dual Edge TPU (8+8 = 16 TOPS)
  • 2x Coral Edge TPU (4+4 = 8 TOPS)

After my first faltering attempt in my testing of Raspberry Pi's new AI Kit, I decided to try building it again, but with a more 'proper' PCIe setup, with external 12V power to the PCIe devices, courtesy of an uPCIty Lite PCIe HAT for the Pi 5.

Raspberry Pi 55 TOPS AI Board

I'm... not sure it's that much less janky, but at least I had one board with a bunch of M.2 cards instead of many precariously stacked on top of each other!

Testing Raspberry Pi's AI Kit - 13 TOPS for $70

Raspberry Pi today launched the AI Kit, a $70 addon which straps a Hailo-8L on top of a Raspberry Pi 5, using the recently-launched M.2 HAT (the Hailo-8L is of the M.2 M-key variety, and comes preinstalled).

Raspberry Pi AI Kit

The Hailo-8L's claim to fame is 3-4 TOPS/W efficiency, which, along with the Pi's 3-4W idle power consumption, puts it alongside Nvidia's edge devices like the Jetson Orin in terms of TOPS/$ and TOPS/W for price and efficiency.

Google's Coral TPU has been a popular choice for a machine learning/AI accelerator for the Pi for years now, but Google seems to have left the project on life support, after the Coral hardware was scalped for a couple years about as badly as the Raspberry Pi itself!

A PCIe Coral TPU FINALLY works on Raspberry Pi 5

Coral.ai TPUs are AI accelerators used for tasks like machine vision and audio processing. Raspberry Pis are often integrated into small robotics and IoT products—or used to analyze live video feeds with Frigate.

Until today, nobody I know of has been able to get a PCI Express Coral TPU working on the Raspberry Pi. The Compute Module 4, unfortunately, had some quirks in its PCIe implementation, preventing the use of the Coral over PCIe.

Google Coral TPU running over PCIe on Raspberry Pi 5

The Raspberry Pi 5 has a much improved PCIe bus—capable of reaching Gen 3 speeds even!—and I've already tested the first PCIe NVMe HATs for Pi 5.

So can the Pi 5 handle the Coral TPU natively over PCIe?

Yes. Though currently, you need to tweak a few things to get it working.