I2CInterface

class I2CInterface(

name: str,

driver: I2CDriverBase,

system_definition: SystemDefinition,

publishers: list[Publisher] | None = None,

**kwargs,

)

Bases: Instrument

I2C interface supporting register-based and command-based devices.

Commands are enum values OR’d together and sent as a single byte stream. The SystemDefinition is read-only — I2CInterface resolves names to transactions on every call; the vendor driver never sees it.

Initialize an I2CInterface.

Parameters:

• name – Channel-name prefix for published data.

• driver –

  Concrete I2C-adapter driver; owns its own transport:

  i2c = I2CInterface(
      "main",
      driver=Aardvark(serial_number="2239-764425"),
      system_definition=system,
  )
  

• system_definition – Bus description (devices, register maps, comms params).

• publishers – Publishers that receive emitted Measurement/Command data.

• **kwargs – Default tags applied to every emitted Measurement/Command. Pass dataset_rid="<rid>" to auto-create a NominalCorePublisher (uses the on-disk ‘default’ Nominal credential).

Attributes

background_interval	Seconds between background daemon iterations (0 = no wait).
channel_names	Return an insertion-ordered snapshot of all published channel names.

Methods

add_background_daemon_function	Append method to the daemon's call list.
add_publisher	Register a publisher to receive this instrument's Measurement/Command data.
close	Close the underlying driver and stop the daemon.
define_background_daemon	Replace all daemon functions with a single method (called with the given args).
get_channel	Return the most recent length samples for channel_name from the in-memory buffer.
get_single_channel_value	Return the most recent sample for channel_name from the in-memory buffer.
open	Open the underlying I2C-adapter driver.
publish	Fan data out to every configured publisher; kwargs pass through.
query	Send a batch command (OR of its enum members) to peripheral and read the response.
read	Read a register (or one of its named fields) on peripheral.
read_raw	Read length bytes from the 7-bit I2C address and decode as an integer.
reset_reg	Write a register's defined default value back to hardware (initialization/recovery).
start	Start the background daemon thread.
stop	Signal the background daemon to stop and join it.
write	Write a register (or one of its named fields) on peripheral.
write_raw	Write data to the 7-bit I2C address.
write_read_raw	Write-then-read without an intermediate I2C STOP (uses repeated START); decode as integer.
write_then_read_raw	Write-then-read with an I2C STOP between operations (required by devices that need STOP to process input).