UpGate#
Over-the-air dynamic reconfiguration of FPGA library and example application.
Introduction#
UpGate takes as input a binary bitstream and works with memory cells based FPGA. UpGate requires a Flash memory, attached to both the FPGA and the microcontroller, and compatible with JEDEC SPI protocol.
The dotbot-upgate.py Python script serves as the “Update controller” used to send the bitstream over-the-air to the FPGA, via the “Embedded server” running on the microcontroller.
For better speed and power consumption performances, the bitstream can be sent compressed (Gzip andn LZ4 compression methods available).
Security#
Before running dotbot-upgate.py, it is required to run the generate_keys.py script to create the public/private key pair that are used by the Ed25519 signature procotol.
Hardware Setup#
Upgate is meant to work with this setup:
A Nordic nRF52840DK board running the embedded server and connected via SPI the FPGA Flash memory. An embedded server sample application code is provided here
A Nordic nNRF52840DK running the gateway application provided here. A precompiled version can be downloaded there and flashed using the nRF52840DK instructions provided in this section of the documentation.
The SPI pins used to wire up the embedded server with the Flash memory are:
Function |
Port |
Pin |
|---|---|---|
SCK |
1 |
15 |
MISO |
1 |
14 |
MOSI |
1 |
13 |
CS |
1 |
12 |
PROG |
1 |
11 |
The PROG pin is used to trigger the reconfiguration of the FPGA once the new bitstream has be written with success to the Flash memory.
Installation#
Among different common Python packages, this script requires the pydotbot package to be installed on the system.
To install all the Python dependencies (pydotbot, cryptography, click and tqdm), run:
pip install -r dist/scripts/upgate/requirements.txt