docs: update README for project status and usage

README.md

@@ -19,17 +19,55 @@ This crate is a working-in-progress and not ready for use.
   - [x] I2C blocking
   - [x] MBX, blocking and async
 - MCUs
-  - HPM5300 - currently it's the only supported series
+  - HPM5300
+  - HPM6E00, without PLL setting
 
 ### Toolchain Support
 
 - [probe-rs]
   - [x] [HPM5300 series flash algorithm support](https://github.com/probe-rs/probe-rs/pull/2575)
   - [ ] [JTag support for DAPLink](https://github.com/probe-rs/probe-rs/pull/2578)
 
+## Usage
+
+The best reference is the examples in the `examples` directory and Github actions workflow.
+
+To get it compile, you might need to use the [hpm-metapac] snapshot repo, or build from [hpm-data] yourself.
+
+Edit the `Cargo.toml` to use the git-based dependency:
+
+```toml
+hpm-metapac = { version = "0.0.3", git = "https://github.com/hpmicro-rs/hpm-metapac.git", tag="hpm-data-d9f90671e5b8ebd51c9565484919b4b880b6a23a" }
+```
+
+### Requirements
+
+- A probe(debugger), optional if you are using official HPMicro's development board
+  - FT2232-based (official HPMicro's development board uses this chip)
+  - JLink
+  - DAPLink-based probe
+- A flash tool for your probe, choose one from:
+  - [probe-rs]
+  - [HPM OpenOCD]
+  - JLink
+  - HPMIcro Manufacturing Tool
+- A RISC-V GCC toolchain if you perfer to use OpenOCD(only GDB is needed)
+- A Rust toolchain
+  - `rustup default nightly-2024-06-12` (locked because of bug [rust-embedded/riscv#196](https://github.com/rust-embedded/riscv/issues/196))
+  - `rustup target add riscv32imafc-unknown-none-elf`
+
+### Run the examples
+
+```bash
+cd examples/hpm5300evk
+cargo run --release --bin blinky
+```
+
 ## Contributing
 
 This crate is under active development. Before starting your work, it's better to create a "Work in Progress" (WIP) pull request describing your work to avoid conflicts.
 
 [hpm-data]: https://github.com/andelf/hpm-data
 [probe-rs]: https://github.com/probe-rs/probe-rs
+[hpm-metapac]: https://github.com/hpmicro-rs/hpm-metapac
+[HPM OpenOCD]: https://github.com/hpmicro/riscv-openocd