LEMPA is a combination of software and hardware that brings modern CI/CD practices to firmware flasging. Key features:
- Fully open source hardware and software
- No need for a computer, screen, or keyboard
- LEMPA will fetch latest versions from cloud / local network automatically
- Embedded web based 2-way serial monitor
- Support for mulitiple controllers including the popular ATMega, ATTiny, and ESP
- Web based interface
- RESTful API for automation
- Multi profile
- Plugin based architecture that can used for automatic testing, embedding unique serial number etc.
Click image for short video:
LEMPA is composed of 3 parts:
A custom PCB that contains all the relevant connections required to program:
- ATMega328 (including external oscillator)
- ATTiny
- ESP8266
- Arduino mini pro
- Any other ATMega controller via connector
The board also includes:
- LEDs for visual status (ready, downloading, programing, success, and error)
- Jumper to define which profile to use.
- LED for testing
- Program / download button. Short click to program the MCU, long click to download latest version of the BINs from cloud / local network / shared folder.
The software reads the different profiles and orchestrates the process of downloading new BINs and programming
- Download the software and extract it
- Install avrdude if needed
sudo apt-get install avrdude - Install prequisites:
sudo apt-get install libopenjp2-7andsudo apt-get install libtiff5 - Install required libraries
pip3 install -r requirements.txt - Make sure profiles.json reflects your environment
python3 program.pyorpython3 program.py <profile id>- Make sure you enable RPi interfaces: SPI, I2C, and Serial
The configuration file can contain as many profiles as required.
{
"id": "blinklocal",
"type": "bin",
"jumper" : 1,
"device": "m328p",
"programmer": "linuxspi",
"bins": [
{
"method": "local",
"name": "blinklocal"
}
],
"fuses": {
"lfuse": "0xF7",
"hfuse": "0xD6",
"efuse": "0xFD",
"lock": "0xFF"
},
"plugins": [
{
"name": "serialinjector",
"conf": {
"serialSpeed": 38400,
"fields": [
{
"id": "blinkrate",
"value": 5,
"title": "Blink rate in 100ms. For exampe value of 5 means 500ms off, 500ms on",
"type": "byte"
}
]
}
}
]
},
...
]- id Unique ID for the profile
- type
binorcomposite. Composite allows for multiple profile programming, one after another. - jumper optional If specified, and the relevant profile is chosen with a physical jumper, this profile will be used if none was specified as part of command line parameter.
- device Type of device to program. Not required for ESP. See AVRDude for list of devices
- autodetect If set to true, system will start programming as soon as it detects chip (does not work ESP)
- bins List of bins to upload. For ATMega only one bin is required. For ESP multiple bins can be specified to support SPIFFS Bin method can be one of the following:
| method | description | requred fields |
|---|---|---|
| cloud | Fetch BIN from any URL | url - source of the BIN |
| cloud_gw | GW that will return info about the BIN. Usefull when a service is required in front of the BIN cloud storage | info_url - End point of the service that will retun information about the BIN. The response of this URL must be a valid JSON with url field that points to the actual BIN |
| local | Don't fetch. Valid BIN must be under bins folder. System will not actively fetch anything |
(none) |
| fs | File system copy | src - Path to source bin that needs to be copied |
- plugins System support a simple web server with the ability to send data to the ATMega via serial. This allows for parameter tweaking and QA.
Once LEMPA is up and running, It exposes web UI via port 8080 that allows:
- Live view of system actions
- Full working 2 way serial monitor. ATMega328 is connected by default to RPi serial0. External boards can be connected via dedicated headers on the HAT
- Operation log
- System control
Please contact me at roey@benamotz.com with any comments