drvAsynI2C

This module provides EPICS device support for accessing I2C bus.

Dependencies

• EPICS base 3.14.12.5 (or newer)
• asynDriver 4-26 (or newer)
• i2c-tools

Installation

1. Edit "configure/RELEASE" according to your environment
2. Type make inside the top directory

Usage

Loading the driver

To load the driver use the command inside the IOC

drvAsynI2CConfigure( "NAME", "I2Cbus", autoConnect )

where NAME is the name used by asyn to identify the driver, I2Cbus is the name of the I2C device on the filesystem and autoConnect is a flag whether the driver should automatically connect to the device or not.

Writing to/Reading from the bus

The driver provides an asynOctet interface for reading from/writing to the bus. This interfaces uses a binary format. The first byte of a write command is always treated as the slave address on the bus without the R/!W bit. The setting of this bit is managed by the kernel module. All following bytes will be send to the slave device.

The directory example contains a small IOC controlling an AD7998 ADC via streamDevice. (Note: This example uses also the devGpio device support which can also be found on github )

Using StreamDevice

Refer to the readme inside the directory "streamDevice"

Known Issues

• none