culvert-async-0.1.0 has been yanked.

culvert-async

Async typed access to the HDMI 2.1 SCDC register map.

culvert-async is the async companion to [culvert], following the same design split as embedded-hal / embedded-hal-async. It mirrors [culvert::Scdc] with async fn methods, wrapping an [hdmi_hal_async::scdc::ScdcTransport] instead of a sync transport. All register types and error types are re-exported from culvert so callers do not need both crates.

Usage

[dependencies]
culvert-async = "0.1"

Wrap your async transport in Scdc and await typed methods:

use culvert_async::{Scdc, TmdsConfig, FrlConfig, FrlRate, FfeLevels};

let mut scdc = Scdc::new(transport);

// Version negotiation
let sink_ver = scdc.read_sink_version().await?;
scdc.write_source_version(1).await?;

// Enable TMDS scrambling
scdc.write_tmds_config(TmdsConfig {
    scrambling_enable: true,
    high_tmds_clock_ratio: true,
}).await?;

// Request an FRL rate
scdc.write_frl_config(FrlConfig {
    frl_rate: FrlRate::Rate12Gbps4Lanes,
    ffe_levels: FfeLevels::Ffe3,
    dsc_frl_max: false,
}).await?;

// Poll for training readiness
let flags = scdc.read_status_flags().await?;
if flags.flt_ready {
    // sink is ready for the LTP loop
}

// Read per-lane character error counts
let ced = scdc.read_ced().await?;
if let Some(count) = ced.lane0 {
    // lane 0 has a valid error count
}

To use culvert-async as the SCDC backend for plumbob-async's link training state machine, enable the plumbob-async feature:

[dependencies]
culvert-async  = { version = "0.1", features = ["plumbob-async"] }
plumbob-async  = "0.1"

Scdc<T> then implements plumbob_async::ScdcClient automatically.

Register coverage

Register group	Addresses	Methods
Version	0x01–0x02	`read_sink_version`, `write_source_version`
Update flags	0x10–0x11	`read_update_flags`, `clear_update_flags`
TMDS / scrambling	0x20–0x21	`write_tmds_config`, `read_scrambler_status`
FRL config	0x30	`write_frl_config`
FRL status	0x40–0x41	`read_status_flags`
Character Error Detection	0x50–0x57	`read_ced`

Features

Feature	Default	Description
`plumbob-async`	no	Implements `plumbob_async::ScdcClient` for `Scdc<T>`

`no_std`

culvert-async is #![no_std] throughout. All output types are stack-allocated; no allocator is required in any configuration.

Stack position

flowchart LR
    dt["display-types"]
    hal["hdmi-hal / hdmi-hal-async"]
    culvert["culvert"]
    culvert_async["culvert-async"]
    plumbob_async["plumbob-async"]
    integration["integration layer"]

    dt --> culvert
    hal --> culvert
    hal --> culvert_async
    culvert --> culvert_async
    culvert_async -->|"implements ScdcClient"| plumbob_async
    plumbob_async -->|"implements LinkTrainer"| integration

culvert-async does not depend on plumbob-async. The relationship runs the other way: enabling the plumbob-async feature makes Scdc<T> implement plumbob_async::ScdcClient. Any crate that implements ScdcClient is substitutable.

Out of scope

Sync API — callers on sync transports use [culvert] directly.
Link training state machine — the sequencing of FRL training belongs in plumbob-async. culvert-async provides the register operations; the state machine decides when to call them.
PHY configuration — HdmiPhy operations are the link training layer's concern.
I²C / DDC transport — platform backends implement hdmi_hal_async::scdc::ScdcTransport. culvert-async never touches I²C directly.

Documentation

doc/setup.md — build, test, coverage, and example commands
doc/testing.md — testing strategy, transport harness, and CI expectations
doc/architecture.md — role, scope, module structure, design principles, and implementation plan
doc/roadmap.md — deferred register groups and planned API surfaces

License

Licensed under the Mozilla Public License 2.0.

culvert-async 0.1.0