Zephyr TensorFlow-Micro EthosU Sample on EK-RA8P1

Application: TensorFlow Lite for Microcontrollers on Arm Ethos-U — Zephyr Project Documentation

Generating Vela-compiled Model

1. Download the Model and Test Script

Download the following files from ARM model zoo:

• cnn_s_quantized.tflite
• testing_input/input/0.npy
• testing_output/identity/0.npy

2. Open the Bash and Create a Virtual Environment

$ cd path/to/your/model/folder
$ python3 -m venv .venv

3. Source with python virtual environment and install ethos-u-vela:

For Windows with Git bash:

$ source .venv/Scripts/activate 
$ pip install ethos-u-vela

For Linux:

$ source .venv/bin/activate 
$ pip install ethos-u-vela

4. Optimizing the model for Ethos-U using Vela (RA8P1 is using ETHOS U55 256 variant):

$ vela cnn_s_quantized.tflite --output-dir . --accelerator-config ethos-u55-256 --system-config Ethos_U55_High_End_Embedded --memory-mode Shared_Sram

5. Removing unnecessary header:

$ dd if=testing_input/input/0.npy of=testing_input/input/0_no-header.npy bs=1 skip=128
$ dd if=testing_output/identity/0.npy of=testing_output/identity/0_no-header.npy bs=1 skip=128

6. Converting to C array:

$ xxd -c 16 -i cnn_s_quantized.tflite cnn_s_quantized.tflite.h
$ xxd -c 16 -i cnn_s_quantized_vela.tflite cnn_s_quantized_vela.tflite.h
$ xxd -c 16 -i testing_input/input/0_no-header.npy testing_input/input/0_no-header.npy.h
$ xxd -c 16 -i testing_output/identity/0_no-header.npy testing_output/identity/0_no-header.npy.h

After execute above steps, you will get below output file

• cnn_s_quantized_vela.tflite.h
• testing_input/input/0_no-header.npy.h
• testing_output/Identity/0_no-header.npy.h

Running and verified TensorFlow EthosU sample:

1. Synchronizing to the sample (samples\modules\tflite-micro\tflm_ethosu), replace the sample C array with the output you've generated:

• cnn_s_quantized_vela.tflite.h => model.h
• testing_input/input/0_no-header.npy.h => input.h
• testing_output/Identity/0_no-header.npy.h => output.h

2. Build, flash and verify sample

$ west config manifest.project-filter -- +tflite-micro
$ west update
$ west build -p -b ek_ra8p1/r7ka8p1kflcac/cm85 samples/modules/tflite-micro/tflm_ethosu
$ west flash

Console log: