The ISA-to-I2C card gives your PC access to an I2C bus via the PCF8584 IC. I2C connectivity is provided to the PC interior using a STEMMA connector (JST PH series) operating at 5V, allowing immediate integration with a wide range of STEMMA-compatible I2C devices. External I2C connectivity is offered through a DE-9 connector.

Connectivity

The combination of internal and external connectivity means you could use the internal connector to link up a temperature sensor inside your PC case and still connect an external peripheral using the rear connector.

DE-9 Pinout

The DE-9 connector pinout for external I2C connectivity is described below.

Configuration

A DIP switch allows you to configure your preferred I/O address to avoid conflicts with other ISA cards in your system.

Assembly

These fully assembled cards are tested before shipping to ensure you can get started with the least hassle. Cards will have the DIP switch pre-configured for an I/O address of 0x3A0, but you may tweak this as required for your system.

Documentation

Check out the programming guide and the datasheet attached below to get up and running quickly with an I2C transmission.

You may also wish to inspect the MS-DOS source code example.

You can learn more about the PCF8584 IC at NXP's website.