To get started with either the Mini PCIe or M.2 Accelerator, all you need to do is connect the card to your system, and then install our PCIe driver, Edge TPU runtime, and the TensorFlow Lite runtime. This page walks you through the setup and shows you how to run an example model.
The setup and operation is the same for both M.2 form-factors, including the M.2 Accelerator with Dual Edge TPU.
- Raspberry Pi 5 with the following Linux operating system:
Raspberry Pi OS (64-bit)
based on Debian 10 or newerUbuntu (64-bit)
23.10 or newer.
- All systems require support for MSI-X as defined in the PCI 3.0 specification
- At least one available M.2 module slot
- Python 3.6-3.9.16
- Linux kernel 6.6.20+rpt-rpi-v8. Check with
uname -r
.
- Make sure the host system where you'll connect the module is shut down.
- Carefully connect the M.2 module to the corresponding module slot on the host, according to your host system recommendations. We recommend the PineBerry AI Hat (E-Key) for the Raspberry Pi 5.
Next, you need to install both the Coral PCIe driver and the Edge TPU runtime. You can install these packages on your host computer as follows, on Linux
.
The Coral ("Apex") PCIe driver is required to communicate with any Edge TPU device over a PCIe connection, whereas the Edge TPU runtime provides the required programming interface for the Edge TPU.
-
Run @dataslayermedia 's forked script to install the edge TPU's runtime, Gasket driver, edit boot configuration, Modify the Device Tree Source, and enable Message Signaled Interrupts (MSI) for the PCIe bus.
curl https://gist.githubusercontent.com/Reddimus/c6948d08a4f4b54ee9d075270bd79c3b/raw/0dfb1def9ebe32559597bae07096762f28a334b8/coral-ai-pcie-edge-tpu-raspberrypi-5-setup | sh
If the script does not work please use @dataslayermedia 's script:
curl https://gist.githubusercontent.com/dataslayermedia/714ec5a9601249d9ee754919dea49c7e/raw/76c231b59b9a2b5d1418229765ce4e160587d418/coral-ai-pcie-edge-tpu-raspberrypi-5-setup | sh
-
Verify that the accelerator module is detected:
lspci -nn | grep 089a
You should see something like this:
03:00.0 System peripheral: Device 1ac1:089a
The
03
number andSystem peripheral
name might be different, because those are host-system specific, but as long as you see a device listed with089a
then you're okay to proceed. -
Also verify that the PCIe driver is loaded:
ls /dev/apex_0
You should simply see the name repeated back:
/dev/apex_0
If the accelerator module is detected but
/dev/apex_0
is not found, then read the troubleshooting section at the end of this guide. -
Edit the boot config file to ensure PCIe Gen3 speeds are enabled:
sudo nano /boot/config.txt
Add the following 2 lines to the end of the file:
dtparam=pciex1 dtparam=pciex1_gen=3
Save and exit the file using
Ctrl+X
,Y
,Enter
fornano
. -
Give permissions to the
/dev/apex_0
device by creating a newudev
rule:
Open a terminal and use your favorite text editor with sudo to create a new file in /etc/udev/rules.d/. The file name should end with .rules. It's common practice to start custom rules with a higher number (e.g., 99-) to ensure they are applied after the default rules. For example:sudo nano /etc/udev/rules.d/99-coral-edgetpu.rules
-
Add a rule to the file:
You'll need to identify your device by attributes likeidVendor
andidProduct
or use theKERNEL
attribute if the device path is consistent. For the Coral Edge TPU, using the device path/dev/apex_0
directly in audev
rule is not standard because this path might not be persistent across reboots or other device changes. Instead, use attributes to match the device.However, since we're dealing with a specific device path here, your rule might look something like this, assuming
/dev/apex_0
is consistently named and you're setting permissions:KERNEL=="apex_0", MODE="0666"
This rule sets the device file
/dev/apex_0
to be readable and writable by everyone. Adjust theMODE
as necessary for your security requirements. -
Reload the
udev
rules and trigger them: After saving the file, you need to reload theudev
rules and trigger them to apply the changes without rebooting. Reload the rules:sudo udevadm control --reload-rules sudo udevadm trigger
-
Verify
/dev/apex_0
andMSI-X
are enabled:
Verify that the permissions for/dev/apex_0
are set as expected. After rebooting, check the permissions of the device file:lspci -nn | grep 089a ls -l /dev/apex_0
Also verify all Message Signaled Interrupts (
MSI
) are enabled:sudo lspci -vvv|grep -i MSI-X
You should see something like this, where
+
indicates that MSI-X is enabled and-
indicates that it's disabled:Capabilities: [d0] MSI-X: Enable+ Count=128 Masked- Capabilities: [b0] MSI-X: Enable+ Count=61 Masked-
Note: The use of MODE="0666" makes the device world-readable and writable, which may not be secure for all environments. Consider your security requirements and adjust the permissions accordingly, possibly using GROUP to restrict access to users within a specific group.
Now continue to install PyCoral and TensorFlow Lite.
This guide will walk you through setting up pyenv
to manage different Python versions, specifically how to build Python 3.6
through Python 3.9.16
. This setup is particularly useful for development environments that require access to system-level features like M.2 and Bluetooth on Raspberry Pi.
pyenv
builds Python from source, requiring several dependencies. For Ubuntu/Debian users, you can install these dependencies with the following command:
sudo apt-get install -y make build-essential libssl-dev zlib1g-dev libbz2-dev libreadline-dev libsqlite3-dev wget curl llvm libncurses5-dev libncursesw5-dev xz-utils tk-dev libffi-dev liblzma-dev python3-openssl
The pyenv-installer
simplifies the installation of pyenv
and its associated plugins. Execute the following command to use it:
curl https://pyenv.run | bash
This installs pyenv
along with useful plugins:
pyenv
: The main application for version management.pyenv-virtualenv
: A plugin for managing virtual environments.pyenv-update
: Enables easy updating ofpyenv
.pyenv-doctor
: Checks the installation and build dependencies.pyenv-which-ext
: Enhances command lookup.
Note: The command above is equivalent to manually downloading and executing the
pyenv-installer
script. You can inspect the script before running for security. Alternatively, manual installation instructions are available if preferred.
After installation, you might see a warning about adding pyenv
to your load path. Follow these steps to ensure pyenv
functions correctly in your shell:
-
Edit
~/.bashrc
with your preferred editor:nano ~/.bashrc
-
Append the following lines to
~/.bashrc
(Your warning may look different):export PYENV_ROOT="$HOME/.pyenv" [[ -d $PYENV_ROOT/bin ]] && export PATH="$PYENV_ROOT/bin:$PATH" eval "$(pyenv init -)" eval "$(pyenv virtualenv-init -)"
This configures your shell to initialize
pyenv
andpyenv-virtualenv
automatically. -
Apply the changes: Source your
.bashrc
file to apply the changes immediately:source ~/.bashrc
-
For login shells, repeat steps 1-3 for
~/.bash_profile
or~/.profile
if applicable. This ensurespyenv
initializes correctly in all shell sessions. -
Reload your shell: Use
exec "$SHELL"
or restart your terminal to finalize the setup.
Before installing Python with pyenv
, ensure your system has the necessary tools and libraries. For projects that require Bluetooth, install Bluetooth development headers:
sudo apt-get update
sudo apt-get install -y libbluetooth-dev
This command installs libbluetooth-dev
, essential for Bluetooth development with Python.
To access system libraries, install Python with the --enable-shared
configuration option:
env PYTHON_CONFIGURE_OPTS="--enable-shared" pyenv install 3.9.16
This ensures the Python interpreter can link against shared system libraries, necessary for certain development tasks.
Set the installed Python version as your global default:
pyenv global 3.9.16
You've successfully installed pyenv
and configured it to manage multiple Python versions, with special consideration for system-level access required for hardware interfacing on platforms like Raspberry Pi.
PyCoral is a Python library built on top of the TensorFlow Lite library to speed up your development and provide extra functionality for the Edge TPU.
We recommend you start with the PyCoral API, and we use this API in our example code below, because it simplifies the amount of code you must write to run an inference. But you can build your own projects using TensorFlow Lite directly, in either Python or C++.
First check your Linux system's Python version:
python3 --version
PyCoral currently supports Python 3.6 through 3.9.16
. If your default version is something else, we suggest you install Python 3.9 with pyenv.
To install the PyCoral library, use the following commands based on your Python environment.
sudo apt-get install python3-pycoral
python3 -m pip install --extra-index-url https://google-coral.github.io/py-repo/ pycoral~=2.0
Lastly, check the list of installed packages to verify that PyCoral is installed:
pip3 list
The packages needed should roughly look like this:
Python 3.9.16
Package Version
----------------------------
numpy 1.26.4
Pillow 9.5.0
pip 24.0
pycoral 2.0.0
setuptools 58.1.0
tflite-runtime 2.5.0.post1
Note: Pillow must be 9.5.0 or older.
If you have a newer version, you can downgrade it with:
pip3 install Pillow==9.5.0
Now you're ready to run an inference on the Edge TPU.
Follow these steps to perform image classification with our example code and MobileNet v2:
- Download the example code from GitHub:
mkdir coral && cd coral git clone https://github.com/google-coral/pycoral.git cd pycoral
- Download the model, labels, and bird photo:
bash examples/install_requirements.sh classify_image.py
- Run the image classifier with the bird photo (shown in figure 1):
python3 examples/classify_image.py \ --model test_data/mobilenet_v2_1.0_224_inat_bird_quant_edgetpu.tflite \ --labels test_data/inat_bird_labels.txt \ --input test_data/parrot.jpg
You should see results like this:
----INFERENCE TIME----
Note: The first inference on Edge TPU is slow because it includes loading the model into Edge TPU memory.
11.8ms
2.7ms
2.6ms
2.7ms
2.7ms
-------RESULTS--------
Ara macao (Scarlet Macaw): 0.75781
These speeds are faster compared to running the same model on the Google Coral USB TPU:
----INFERENCE TIME----
Note: The first inference on Edge TPU is slow because it includes loading the model into Edge TPU memory.
20.6ms
7.0ms
6.8ms
5.2ms
5.1ms
-------RESULTS--------
Ara macao (Scarlet Macaw): 0.75781
Congrats! You just performed an inference on the Edge TPU using TensorFlow Lite.
To demonstrate varying inference speeds, the example repeats the same inference five times. Your inference speeds might differ based on your host system.
The top classification label is printed with the confidence score, from 0 to 1.0.
To learn more about how the code works, take a look at the classify_image.py
source code and read about how to run inference with TensorFlow Lite.
Note: The example above uses the PyCoral API, which calls into the TensorFlow Lite Python API, but you can instead directly call the TensorFlow Lite Python API or use the TensorFlow Lite C++ API. For more information about these options, read the Edge TPU inferencing overview.
Important: To sustain maximum performance, the Edge TPU must remain below the maximum operating temperature specified in the datasheet. By default, if the Edge TPU gets too hot, the PCIe driver slowly reduces the operating frequency and it may reset the Edge TPU to avoid permanent damage. To learn more, including how to configure the frequency scaling thresholds, read how to manage the PCIe module temperature.
To run some other models, such as real-time object detection, pose estimation, keyphrase detection, on-device transfer learning, and others, check out our example projects. In particular, if you want to try running a model with camera input, try one of the several camera examples.
If you want to train your own model, try these tutorials:
- Retrain an image classification model using post-training quantization (runs in Google Colab)
- Retrain an image classification model using quantization-aware training (runs in Docker)
- Retrain an object detection model using quantization-aware training (runs in Docker) Or to create your own model that's compatible with the Edge TPU, read TensorFlow Models on the Edge TPU.
The following section describes how the power throttling works and how to customize the trip points.
Here are some solutions to possible problems on Linux.
If you receive an error messages such as the following when you run an inference...
HIB Error. hib_error_status = 0000000000002200, hib_first_error_status = 0000000000000200
... You should be able to solve it if you modify your kernel command line arguments to include gasket.dma_bit_mask=32
.
For information about how to modify your kernel command line arguments, refer to your respective platform documentation. For bootloaders based on U-Boot, you can usually modify the arguments either by modifying the bootargs
U-Boot environment variable or by setting othbootargs environment variable as follows:
=> setenv othbootargs gasket.dma_bit_mask=32
=> printenv othbootargs
othbootargs=gasket.dma_bit_mask=32
=> saveenv
If you make the above change and then receive errors such as, DMA: Out of SW-IOMMU space
, then you need to increase the swiotlb
buffer size by adding another kernel command line argument: swiotlb=65536
.
If you see a lot of errors such as the following:
pcieport 0000:00:01.0: PCIe Bus Error: severity=Corrected, type=Data Link Layer, id=0008(Transmitter ID)
pcieport 0000:00:01.0: device [10de:0fae] error status/mask=00003100/00002000
pcieport 0000:00:01.0: [ 8] RELAY_NUM Rollover
pcieport 0000:00:01.0: [12] Replay Timer Timeout
pcieport 0000:00:01.0: PCIe Bus Error: severity=Uncorrected (Non-Fatal), type=Transaction Layer, id=0008(Requester ID)
pcieport 0000:00:01.0: device [10de:0fae] error status/mask=00004000/00000000
... You should be able to solve it if you modify your kernel command line arguments to include pcie_aspm=off
.
For information about how to modify your kernel command line arguments, refer to your respective platform documentation. If your device includes U-Boot, see the previous HIB error for an example of how to modify the kernel commands. For certain other devices, you might instead add pcie_aspm=off
to an APPEND
line in your system /boot/extlinux/extlinux.conf
file:
LABEL primary
MENU LABEL primary kernel
LINUX /boot/Image
INITRD /boot/initrd
APPEND ${cbootargs} quiet pcie_aspm=off
The following procedure is necessary only if your system includes a pre-build driver for Apex devices (as per the first steps for installing the PCIe driver). Due to a bug, updating this driver with ours can fail, so you need to first disable the apex
and gasket
modules as follows:
- Create a new file at /etc/modprobe.d/blacklist-apex.conf and add these two lines:
blacklist gasket blacklist apex
- Reboot the system.
- Verify that the apex and gasket modules did not load by running this:
It should print nothing.
lsmod | grep apex
- Now follow the rest of the steps to install the PCIe driver.
- Finally, delete
/etc/modprobe.d/blacklist-apex.conf
and reboot your system.
Ensure the Kernel Moudle is Loaded
Check if the gasket
and apex
kernel modules are loaded properly. You've already checked for apex
, but let's ensure everything is set up correctly:
lsmod | grep gasket
lsmod | grep apex
If they're not listed, try manually loading them:
sudo modprobe gasket
sudo modprobe apex
If you see the following error message continue reading:
modprobe: FATAL: Module gasket not found in directory /lib/modules/6.1.0-rpi8-rpi-2712
modprobe: FATAL: Module apex not found in directory /lib/modules/6.1.0-rpi8-rpi-2712
The error messages from modprobe
indicate that the gasket
and apex
modules are not found in your current kernel's module directory. This suggests that either the modules are not installed correctly, or they are not compatible with your current kernel version (6.1.0 for Raspberry Pi). Here are some steps you can take to address this issue:
-
Ensure Kernel Headers are Installed For modules like
gasket
andapex
to be built and installed properly, you need the kernel headers for your currently running kernel. Install the kernel headers with:sudo apt-get install raspberrypi-kernel-headers
After installing the headers, try reinstalling the gasket-dkms and libedgetpu1-std packages, as DKMS should automatically build the modules against your current kernel:
sudo apt-get reinstall gasket-dkms libedgetpu1-std
-
Check DKMS Status After installing the kernel headers and reinstalling the packages, check the status of DKMS to see if the
gasket
andapex
modules have been built:dkms status
This command will list all DKMS modules and their status. You're looking for gasket and apex to be listed as installed for your kernel version.
You should roughly see the following output:
Deprecated feature: REMAKE_INITRD (/var/lib/dkms/gasket/1.0/source/dkms.conf) Deprecated feature: REMAKE_INITRD (/var/lib/dkms/gasket/1.0/source/dkms.conf) gasket/1.0, 6.1.0-rpi8-rpi-2712, aarch64: installed gasket/1.0, 6.1.0-rpi8-rpi-v8, aarch64: installed
-
Reboot
sudo reboot
You can now continue with the rest of the steps to install the PCIe driver.
Hi everyone,
I noticed that the script currently uses sudo apt-key add to add a repository key, which has been deprecated. Here is the updated part of the script to use a more modern approach that's recommended for Debian systems.
Happy coding! 🎉