view wiki/Modules.md @ 787:aeb72882f30a

Dev Bugfx Empty buffer indication and stability improvments: The mux prototype used ASCII coding for channel selection while the current realization used real number (0...4) for addressing the mux. The UART read function uses the '0' to indicate an empty buffer element. The mux now loops back '0' used by channel selection causing the read function to process the data. As result data interrups are visible at the display. To avoid this another character has been defined indicate empty buffer locations. Beside this the functionality has been improved with regard to access speed and better recovery in case of transition failure.
author Ideenmodellierer
date Sun, 04 Jun 2023 21:59:26 +0200
parents 0e7c16dd774d
children
line wrap: on
line source

# OSTC4 Code Modules #

## Main CPU - aka CPU1-Discovery ##

For historical reasons, the firmware of the main CPU was divided in three parts.
It helps development, allow smalled upgrades, and improve security as a bad manipulation won't kill the bootloader, responsible fot the next firmware upgrade.

### Bootloader ##

The code responsible to upload new firmwares for both CPU.

### Font Pack ###

This module does not contains any code. Just font data and images.

### Firmware code ###

The main OSTC4 firmware. The more important modules are:

- Buehlmann decompression algorithm.
- VPM decompression algorithm.
- The simulator and dive planner.
- Logbook display (surface and dive mode).
- All user interface code, during dive or surface mode (`t*.c` files).
- Graphics (gfx) engine.
- Plus interface to the other CPU, the management of the _LCD_ screen, and the optional _Bonex_ scooter interface (No longer supported)

## Small CPU - aka CPU2-RTE ##

The _Real Time_ CPU handle everything that requires precise timming to function perperly.

The most important modules are:

- Real time computation of gas exchanges during dive (aka the _LifeData_ structure).
- Analog to digital conversion for the ... ambient light sensor.
- I2C bus interface to the pressure sensor, the magnetic compass and the battery gauge.
- SPI bus interface to the buttons and to the other CPU.
- Serial interface to the _RS232-over-Wireless_ connection.