I am using the Aardvark I2C/SPI Host Adapter in SPI slave mode, with MATLAB to interface with the Aardvark adapter. The master outputs a packet that we would like to read. But we aren’t able to read our entire packet, because it appears that the data output is limited to 8 bits. In the header file, the SPI slave read data output only is an 8-bit variable. Is there a way to work around this?

Thanks for your question! The Aardvark adapter supports 8-bit words and can transfer 8-bit SPI data without td delay, and multiple 8-bit SPI data with td delay.  To send data that is non-8 bit packets, we recommend the Promira Serial Platform.

Figure 1: Promira Serial Platform

The Promira platform supports multiple 8-bit words as well as multiple non 8-bit words, which provides greater flexibility for interfacing with the more complex devices. You could find the Promira platform very useful for many projects – it provides many built-in features including:

• Integrated level shifting from 0.9-3.3V (5V tolerant)
• High-speed USB connectivity and Ethernet connectivity
• Provides 200 mA to target devices
• Scalability - SPI and I2C Active applications allow you to upgrade your Promira platform as needed; new applications will be released on a ongoing basis

Here is a summary of the SPI Active application features, which can be quickly and easily downloaded to the Promira platform.

Figure 2: Comparison Chart,  Promira and Aardvark Features

Additional resources that you may find helpful include the following:

• Aardvark I2C/SPI Host Adapter User Manual

• Promira Serial Platform User Manual

• How to Use Total Phase Products with MATLAB

We hope this answers your questions. If you have other questions about our host adapters or other Total Phase products, feel free to email us at sales@totalphase.com, or if you already own one of our devices and have a technical question, please submit a request for technical support.