Question from the Customer:
I am attempting to monitor my 4 MHz SPI application with 16-bit transfers with a slave device. I have been using the Aardvark I2C/SPI Host Adapter with the Control Center Software. When using the slave mode, data will begin to slow and then the tool "locks up" after short periods of time. In taking a close look at the timing of the SPI devices under test, there appears to be a timing conflict with the Aardvark adapter. The timing (td) between the start of the bytes is 2-5 us. However, the setup time for the Aardvark is 4 us.
Looking at the Total Phase products, I seem to have some options - which device or devices do you recommend for this project?
Response from Technical Support:Thanks for the question! As a slave in SPI mode, the timing setup of the Aardvark I2C/SPI Host Adapter does require 4 us between bytes, which is not compatible with the 2-5 us delay. Our latest device, the Promira Serial Platform, will meet your SPI timing requirements.
Figure 1: Promira Serial PlatformWith the current SPI Active - Level 1 Application, the Promira platform supports active communication on the bus, in addition it offers:
- Built-in level shifting 0.9 V – 3.3 V
- A total of 200 mA of power to the target devices
- USB 2.0, USB 2.0 over Ethernet and Ethernet connectivity.
- Slave programming up to 8 MHz
- Master programming up to 12.5 MHz
For more information about the Promira's timing parameters, please refer to section 6.2 of the Promira Serial Platform User Manual. For more aggressive requirements, new, more powerful applications will become available Q2 this year - which will be easy to access, as the Promira platform is field upgradeable.
Aside from active devices like the Aardvark adapter and Promira platform, you might find our protocol analyzers helpful.
Figure 2: Beagle I2C/SPI Protocol AnalyzerThe Beagle I2C/SPI analyzer is a low-cost non-intrusive bus monitor, which can monitor SPI up to 24 MHz burst, I2C up to 5 MHz, and MDIO up to 2.5 MHz. With the Data Center Software, the Beagle analyzer displays and filters your bus data in real time, giving you much more visibility into what’s going on in your application.
Additional resources that you may find helpful include the following:
- Promira Serial Platform User Manual
- Control Center Serial Software User Manual
- Beagle Protocol Analyzer User Manual
- Data Center Software User Manual
We hope this answers your question. If you have other questions about our host adapters, protocol analyzers 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.