System76 EC is a GPLv3 licensed embedded controller firmware for System76 laptops. It is designed to be portable to boards using several 8-bit microcontrollers, such as:
Board | Embedded Controller | Architecture |
---|---|---|
System76 ecsim | Simulated ITE EC | 8051 |
System76 Laptops | ITE IT8587E | 8051 |
System76 Thelio Io | Atmel ATMEGA32U4 | AVR |
Arduino Mega 2560 | Atmel ATMEGA2560 | AVR |
Shared features (that can be used across different micro-controllers):
Acronym | Feature | Description |
---|---|---|
ADC | Analog-digital converter | Reads voltages from batteries and temperature from thermistors |
DAC | Digital-analog converter | Brightness control of keyboard backlight |
GPIO | General purpose input/output | Control of LED's, buttons, and enable lines for other hardware |
KBSC | Keyboard scan controller | Detects laptop keyboard presses. Keyboard scanning can be done using GPIOs, the ITE EC has hardware acceleration |
PS/2 | Keyboard and mouse bus | Interfaces with touchpad. PS/2 can be done using GPIOs, the ITE EC has hardware acceleration |
PWM | Pulse-width modulation | Fan control and brightness control of LED's |
SMBUS | System management bus | Reads battery information |
SPI | Serial peripheral interface | Reads and programs the EC's firmware |
UART | Universal asynchronous receiver-transmitter | Provides EC console input/output |
Features specific to ITE embedded controllers:
Acronym | Feature | Description |
---|---|---|
LPC | Low pin count | Forwards memory and I/O access to EC. Most EC functions are exposed to the host through this interface. High frequency makes a GPIO implementation not possible. Simulation is provided by System76 ecsim |
PECI | Platform environment control interface | Reads CPU temperature (relative to throttle point). Proprietary nature means a GPIO implementation is unlikely, though not technically impossible |
Features specific to Atmel embedded controllers:
Acronym | Feature | Description |
---|---|---|
USB | Universal serial bus | Can be used to provide access to EC functions either to the host or to a remote machine |
Requirements:
Use this method for flashing a system already running System76 EC.
make BOARD=<vendor>/<model> flash_internal
Use this method for first-time flashing or flashing a bricked controller.
The system must not have any power!
- Turn off the computer
- Unplug the AC adapter
- Remove the bottom panel
- Disconnect the battery
- Ground the laptop to the programmer
- Disconnect the keyboard from its port
- Attach the programmer to the keyboard port
- Flash the firmware
make BOARD=<vendor>/<model> flash_external