System validation, stress testing, and regression testing are essential for debugging I2C/SPI-based systems and ensuring they perform reliably under all operating conditions. Validation testing verifies that the device under test (DUT) functions correctly and as expected across a range of scenarios, while regression testing verifies that system changes, such as hardware or firmware updates, do not break existing functionality. Stress testing evaluates how the system performs under extreme conditions or heavy loads, helping to identify potential failure points. Automating these workflows improves consistency, repeatability, and test coverage.

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Types of Testing Workflows for Validating I2C and SPI Device Communication

• System integration testing is conducted to verify proper communication between multiple devices sharing the same I2C or SPI bus. This stage verifies that MCUs, sensors, and other peripherals are communicating properly and as expected. This testing can uncover bus conflicts that are a result of incorrect device addressing, bus arbitration errors, data packet corruption.
• Stress testing is done to evaluate device limits and overall reliability by deliberately pushing a system beyond its normal operational limits. With automated scripts, a system can be flooded with a high volume of information/data, revealing how the device will perform under extreme conditions.
• Regression testing after hardware or firmware updates will verify that the change does not cause new communication errors to arise. This is an especially crucial part of deploying any firmware updates, because the firmware might not sync compatibly with hardware due to timing, sequencing, or clock configuration changes.

Challenges in I2C/SPI System Validation and High-Volume Testing

Validating system components, such as sensor responses, and running high-volume stress/regression tests without the right tools can make it difficult to efficiently manage complex test sequences, ultimately slowing development.

Manual approaches to system integration testing may fall short when it comes to validating how components respond across a wide range of scenarios. Without effective automation or streamlined test sequencing, thoroughly exercising system behavior and confirming expected responses becomes challenging.

Similarly, high-volume testing, like stress testing, often require sending a large volume of commands in sequence, making the right tool essential for streamlining the process. The ideal host adapter should deliver high speed, low latency, and advanced queuing capabilities to run multiple tests efficiently without delays.

Using Batch Scripts to Automate I2C/SPI Device Testing

Automating I2C/SPI system validation and other tasks using a Total Phase host adapter streamlines testing workflows, expands test coverage across various scenarios, and boosts scalability. Automation also standardizes procedures by ensuring tests run consistently with the same parameters and are easily repeatable.

Batch scripting is commonly used to automate such tasks during development to confirm that I2C or SPI devices respond correctly and consistently across multiple test cycles. It enables sequential communication checks on one or more units to verify behavior such as responding to address queries, providing sensor readings, or acknowledging register writes.

Our host adapters support batch scripting of I2C and SPI commands through Batch Mode in Control Center Serial Software or programmatically via our API.

Using Batch Mode in Control Center Serial Software, users can efficiently run a full set of tests on I2C/SPI devices using a single XML-based script. This feature is ideal for quickly configuring scripts for benchtop testing to read/write to a DUT. Instructions on how to set up an XML batch script and specific commands can be found in section 5 of the Control Center Serial Software User Manual.

Using Batch Mode in Control Center Serial Software with the I2C/SPI Activity Board as a Target Device

See our video on using the Promira Serial Platform in Batch Mode.

For greater control, flexibility, and variation in commands within scripts, APIs are also available for this application. While all of our host adapters support batch scripting, the Promira Serial Platform is our most advanced solution and best suited for high-performance use cases.

With its pipelined architecture, High-speed USB (480 Mbps), and Gigabit Ethernet connectivity, the Promira platform delivers significantly faster scripting and lower latency than previous-generation tools. Advanced command queuing and gapless shifting eliminate inter-byte delays, allowing up to 32 bits of data to stream continuously over 32 uninterrupted clock cycles—ideal for high-throughput applications. In addition, multiple Promira platforms can be also be used to stress test multiple buses.

The Promira platform supports up to 127 different queues, each holding up to 255 commands, and allows users to run both sync and async queues via the Promira Software API. Looping functionality within these scripts makes it easy to repeat sequences or run stress tests across a wide range of edge cases and timing scenarios.

Here is an I2C Transfer Example using the Promira API Queue Mechanism:

1. Call ps_queue_create to create a queue, and specify the queue type (e.g. PS_MODULE_ID_I2C_ACTIVE).
2. Call ps_queue_clear to clear the queue.
3. Call ps_queue_i2c_write to add an I2C write command to the queue.
4. Call ps_queue_i2c_read to add an I2C read command to the queue.
5. Call ps_queue_submit to send out the accumulated commands on the I2C bus.
6. Call ps_collect_resp to collect the next response.

   1. The return value of ps_collect_resp will be PS_I2C_CMD_WRITE.
   2. Call ps_collect_i2c_write to collect the response of the I2C write.

7. Call ps_collect_resp to collect the next response.

   1. The return value of ps_collect_resp will be PS_I2C_CMD_READ.
   2. Call ps_collect_i2c_read to collect the response of the I2C read.

8. Repeat step 7 until ps_collect_resp returns PS_APP_NO_MORE_CMDS_TO_COLLECT.
9. Call ps_queue_destroy to destroy the queue or go back to step 6 to submit the queue again.

Further instructions on command queuing, including for SPI transfers, can be found in section 5.5 of the Promira Serial Platform User Manual.

Total Phase Tools that Support Task Automation

The Promira Serial Platform is our most advanced serial device with downloadable applications for I2C or SPI master/slave emulation and eSPI protocol analysis. It supports I2C master and slave speeds up to 3.4 MHz and SPI master and slave speeds up to 80 MHz and 20 MHz respectively, supports Dual and Quad SPI, and has gigabit Ethernet and High-Speed USB connectivity options. Its Ethernet connectivity uniquely provides remote access to the tool, which can further streamline validation and regression testing, programming, and collaborative work amongst global teams.

The Aardvark I2C/SPI Host Adapter is a fast and powerful I2C bus and SPI bus host adapter that operates in master or slave mode and allows developers to transfer serial messages. It supports I2C master/slave speeds up to 800 kHz, SPI master speeds up to 8 MHz, and slave speeds up to 4 MHz. Additional features include I2C multi-master support, inter-bit and inter-byte clock stretching, and SPI full duplex master transmit/receive capabilities.

The Cheetah SPI Host Adapter is specifically designed to communicate with High-speed, SPI-based Flash memory. It can communicate as an SPI master at up to 40+ MHz, supports up to 3 slave selects, and includes transaction queuing for maximum throughput.

For more information on how our tools can support validation and stress/regression testing for I2C/SPI devices, please email us at sales@totalphase.com or request a demo.