Module i2c 

The bus half of CMD_I2C_TRANSFER and CMD_I2C_SCAN, over any embedded-hal-async bus.

transfer_with and scan_with are the part that is the same on every board: turning the staged operation list into HAL operations that read straight into the result buffer, walking a scan range, and naming what went wrong in the protocol’s terms. guarded_transfer and guarded_scan add what a board with a shared bus needs around them—a bounded wait for the bus mutex, a deadline on the transaction, and a Reservation through which the board’s own multi-transaction procedures keep a host out of a peripheral mid-procedure. A board with an exclusively owned bus can call the bare functions instead.

Structs

Held

A Reservation in force; dropping it releases the peripheral.

Reservation

The peripheral one of the board’s own multi-transaction procedures currently holds, if any.

Traits

Reservations

Independent board procedures may reserve different devices concurrently.

Functions

deadline_for

How long a transaction moving octets on a bus clocked at speed_khz may take before it is declared stuck.

guarded_scan

The scan counterpart of guarded_transfer: a range that covers a held address is refused whole rather than silently skipping it, so the host learns to try again instead of drawing a wrong inventory.

guarded_transfer

Acquire bus within lock_timeout, refuse the transfer if reserved holds its address, and perform it within deadline.

scan_deadline

The deadline for a whole scan: an address and a probe octet per address in the range.

scan_with

Probe every address in request’s range with a one-octet read, writing the addresses that acknowledged into out in ascending order and returning how many.

status_for

The status a HAL error kind answers with.

transfer_deadline

The deadline for a transfer of shape: its data plus one address octet per operation.

transfer_with

Perform request on bus, writing the concatenated read data into out and returning its length.