CRSF MicroArch Doc

Rough Notes

 

Crossfire Communication Protocol

 

  • Operates on the 900MHz band frequency

  • Allows for better signal penetration through objects

  • Reduces variable latency between CRSF and OpenTx modules

  • Uses openTx

 

Single wire half duplex communication

Master sends 1 frame every 4ms, slave replies between 2 frames from the master

420000 baud

Not inverted

Big endian

 

BetaFlight:

  • Has a struct that contains data about the connection status and strength such as RSSI

    • One for uplink RSSI

    • One for downlink RSSI

 

 

 

23.02.14 Note: Formal Doc (Currently just template, will be updated soon)

Principle Engineer

@Hailey Doleweerd

Forced to Review

@Christopher Chung @Anthony Luo

Dragged Along

 

Uplifted

 

Objective

Add Crossfire communication capability to LOS

Due date

Apr 7, 2023

Key outcomes

Design and implement a driver that utilizes Crossfire to replace ppm between RC Link and the Flight Controller.

Status

DESIGN

 Problem Statement

  • Design and implement a driver that utilizes Crossfire to replace ppm between RC Link and the Flight Controller.

 Scope

Current Must Haves:

  •  

Current Must Haves:

  •  

Future Expansion:

  •  

Not in scope:

Tasks Break Down:

 Timeline

This will be determined in a future microarch revision, once the general architecture of the driver is further complete.

30-Jan202306-Feb13-Feb20-Feb27-Feb
Design
Coding
Testing

Design Non-Volitile Storage Arch

Review

Implement

Test Driver

Test Interface

 Implementation Details (Insert LOS_Interface object specs here)

 Actions Items

 

 Milestones and deadlines

Milestone

Owner

Deadline

Status

Milestone

Owner

Deadline

Status

Approved Interface Structure

 

In Progress

Coding

 

 

Driver Testing

 

 

Interface Testing

 

 

 

Open Questions

  • What is the performance & reliability of SDMMC versus SPI?

 Reference materials

  •