| .. | ||
| data | ||
| fu-altos-tool.c | ||
| fu-device-altos.c | ||
| fu-device-altos.h | ||
| fu-plugin-altos.c | ||
| meson.build | ||
| README.md | ||
Altos Support
Introduction
Altos is a 8051 operating system for Altus-Metrum projects. The ChaosKey is a hardware random number generator that attaches via USB.
When the ChaosKey when inserted it appears as a device handled by the kernel with VID 0x1d50 and PID 0x60c6. If pins 1 and 5 are shorted as the device is connected then the bootloader is run, which presents VID 0xfffe and PID 0x000a.
The bootloader communication is not handled in the kernel, and a tty device is created so userspace can communicate with the hardware. Commands the bootloader accept are as follows:
List Information
Command: l\n
Several lines of text about the device are transferred to the host, e.g.
altos-loader
manufacturer altusmetrum.org
product AltosFlash
flash-range 08001000 08008000
software-version 1.6.8
There doesn't appear to be any kind of end-of-message signal.
Read Flash
Command: R $addr\n where $addr is a memory address 0x8001000->0x8008000.
256 bytes of raw data are then transferred to the host.
Write Flash
Command: W $addr\n where $addr is a memory address 0x8001000->0x8008000.
256 bytes of raw data are then transferred to the device.
Application Mode
Command: v\n
The device will reboot into application mode. This is typically performed after
flashing firmware completes successfully.