I2C Device

The I2C (Inter-Integrated Circuit) Device IP core is a flexible interface designed to handle and process I2C transmissions. It features an internal clock divider, automatic timeout detection for stalled transmissions, and a configurable sampling bit count.

This IP core does not include a bus interface or register mapping; instead, it relies on a backend tailored to the specific application. Communication between the core and the backend is facilitated through command and response data streams.

Data Streams

1. Command Stream

The command stream transmits information from incoming I2C transmissions to the backend, providing all relevant details:

• Data: The 8-bit data received from the controller.

• Reg: A flag indicating whether the data represents a register address.

• Read: A flag specifying if the transmission is a read or write operation.

2. Response

The response stream returns data from the backend to be transmitted during the I2C SCL cycles:

• Data: The 8-bit data returned from the backend, relevant only for read operations.

• Error: A flag indicating an error if the transmission could not be processed correctly.

Configuration

The I2C Device IP core lacks a built-in bus interface, as it relies on a custom backend to manage incoming transmissions.

Parameter

I2c.Parameter defines the IO pins of the I2C Device controller.

I2c.Parameter

Name	Type	Description	Default
Interrupts	Int	Number of interrupt pins from the device to controller.	0

I2cDeviceCtrl.Parameter configures the I2C Device controller.

I2cDeviceCtrl.Parameter

Name	Type	Description	Default
io	I2c.Parameter	Class with IO parameters
clockDividerWidth	Int	Width of the clock divider counter. Must be greater then 0.	16
timeoutWidth	Int	Timeout counter width to calculate a bus timeout. Must be greater then 0.	16
samplerWidth	Int	Number of sample bits. Must be greated then 2.	3
addressWidth	Int	I2C address width. Currently only 7 bit are supported.	7

I2cDeviceCtrl.Parameter has some functions with pre-predefined parameters for common use-cases.

object Parameter {
  def default(interrupts: Int = 0) = Parameter(io = I2c.Parameter(interrupts))
}