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cc13x0-pac-demo

Writing a HAL from scratch

jamesmunns
Repository

README

Writing a HAL from scratch

  • SVD Files
    • We "fixed" some bugs
    • (probably need to check this for correctness later)
  • svd2rust
    • Generated code
    • Used form to split up the code
    • Used cargo fmt and rustfmt to prettify the code
  • PAC - Peripheral Access Crate
    • We had to add some dependencies
    • Looked to other crates for inspiration
    • Found our crate was for a thumbv7m-none-eabi target
      • Cortex-M0/M0+: thumbv6m-none-eabi
      • Cortex-M3: thumbv7m-none-eabi
      • Cortex-M3 w/ HF: thumbv7m-none-eabihf
      • Cortex-M4/M7: thumbv7em-none-eabi
      • Cortex-M4F/M7F: thumbv7em-none-eabihf

Fork in the road

Long term goal: HAL crate

You use a PAC to hand-write a HAL

Today's goal

Just an application that uses the PAC directly

Next steps:

  • Set up an application that uses the PAC
  • Pull up the datasheet
  • Get a basic main running
  • Get a debugger attached, flash code

Set up an Application

  • Make a new project with cargo new --bin $name
  • Create a memory.x
    • Go find "Memory Map" in the datasheet
    • Make sure you have FLASH and RAM locations and amounts correct
    • Used for the linker script
  • Create a .cargo/config
    • Setup automation
    • Set default target
    • Tell cargo where to look for the linker script
  • Create a debug.gdb
  • Add a panic handler crate
  • Edit src/main.rs
    • Don't forget to include your pac

GET THE DEBUGGER RUNNING

Using the PAC interfaces

Useful for reading, writing, and modifying registers

VOCAB FOR PACs

  • READ: Means read from the register
    • Interact with the register ONCE
  • MODIFY: Means read, make changes, then write
    • Interact with the register TWICE
  • WRITE: Means take the default value, make changes, then write
    • Interact with the register ONCE

Important Notes:

  • Not all registers have all interfaces
  • Always start with the Peripherals struct from your PAC

License

Licensed under either of

  • Apache License, Version 2.0 (LICENSE-APACHE or
    http://www.apache.org/licenses/LICENSE-2.0)

  • MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)

at your option.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted
for inclusion in the work by you, as defined in the Apache-2.0 license, shall be
dual licensed as above, without any additional terms or conditions.