Indy ITK Version 1.6.8 Release Documentation

The ITK release contains all of the collateral necessary to implement an embedded RAIN RFID reader using the Indy Reader Modules. The most essential contents of the release are the ITK-C and ITK-LT-C libraries, which implement IRI host communications from a host processor to communicate with an Indy Reader Module. The release also contains SDK documentation, configuration examples, and code examples to accompany these libraries, as well as additional documentation about Module behavior.

To download the latest version of the ITK release, visit our online support portal here: (requires login).

To view this documentation online, visit our developer portal here:

For a more thorough introduction to implementing an embedded reader using the Indy Modules, see the Quick Start Guide.

Top Level Contents

Below, find a list of the top-level contents of the ITK Release documentation. Each of the linked sections contain a number of subsections that expand on the listed topics.

Release Notes

The Release Notes describe changes in the current version of the ITK, as well as historical versions and notes about compatibility.

Quick Start Guide

The Quick Start Guide provides an overview of how to implement an embedded RFID reader system using the Indy Modules and the ITK.

Impinj Radio Interface Toolkit for C (ITK-C)

The ITK-C documentation explains the IRI host library in detail, including its functions, structures, key codes, and defines, as well as showing example code snippets and programs. This is the main content of the ITK release documentation. The Quick Reference below povides easy access to the key portions of the IRI host library documentation.

Impinj Radio Interface Toolkit LT for C (ITK-LT-C)

The ITK-LT-C documentation describes the ITK-LT-C, an IRI host library implementation which has lower resource utilization and a smaller feature set than the ITK-C. Common elements of the two ITKs, such as the structures and key codes, are covered only by the ITK-C documentation, so the ITK-LT-C documentation is significantly smaller.

IRI Reader and Library Debugging

The IRI Reader and Library Debugging section describes resources available to help debug unintended behaviors of embedded reader systems built around the Indy readers and IRI host libraries.

Frequently Asked Questions (FAQ)

The FAQ section answers the most common questions about the Indy Modules and the ITK-C and ITK-LT-C host libraries.


The Glossary contains a list of common terms related to RFID and RF systems in general, and specifically Impinj’s embedded reader products.

Reference Materials

The Reference Materials section contains a number of additional documents and resources that contain additional details of the Indy Modules and RAIN RFID not described by the ITK-C documentation.

Regulatory Regions

The Regulatory Regions section describes the regulatory regions currently supported by the Indy reader Modules, and how to use them.

Indy Demo Tool

The Indy Demo Tool documentation explains the functionality and behavior of the Indy Demo Tool GUI.

IRI Host Library Detail Quick Reference

The following links lead to the most commonly used subsections of the documentation about the IRI Host Libraries, useful as a quick reference for embedded developers. For more detailed descriptions of the host libraries, see the IRI Host Library Overview.

Configuration Examples

The Configuration Examples provide compact code snippets demonstrating how to use the IRI Host Libraries to configure the Indy Modules in specific ways.

Code Examples

The Code Examples provide full example programs that demonstrate using the IRI host libraries to implement specific RFID configurations using the Indy Modules. They also demonstrate certain host implementations of the platform-specific elements of the IRI host libraries.

Key Code Listing

The Key Code Listing describes the Key Codes used to communicate with the Indy Modules.

API Functions

The API Functions section describes the IRI host library API functions used to implement an IRI host and communicate with the Indy Modules.


The Structures section describes the structures used by the IRI host library APIs.

Data Types and Defines

The Data Types and Defines section describes the data types and constant defines used by the IRI host library APIs.

Error Codes

The Error Codes section describes error codes returned from IRI host library API function calls that indicate erroneous operating conditions on an Indy Module or IRI host itself.

Stored Settings

The Stored Settings section describes both the stored settings feature and the stored settings file format, which allow Indy Modules to retain some aspects of their configuration across resets or power cycles.






















Copyright © 2016 Impinj, Inc.

Licensed under the Apache License, Version 2.0 (the “License”); you may not use this file except in compliance with the License. You may obtain a copy of the License at

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an “AS IS” BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.

This product is covered by one or more of the following U.S. patents. Other patents pending.