Question from the Customer:
I would like to use the Total Phase Promira Serial Platform to control two GPIO pins and program a 1.8V SPI flash device. I have some questions about the output voltage and signal levels of these pins.
Power is provided to the SPI flash:
- Do I need to have either of the power supply pin sets (VCC target power or VCC IO level power) turned on?
Also, these pins are currently not connected to anything:
- What determines the output voltage of the Promira's GPIO pins?
- What determines the output voltage of Promira's SPI outputs?
Thank you for your questions! You can easily configure the Promira level shift value (from 0.9V to 3.45V) with the Control Center Serial, Flash Center, or Promira API software. This configuration controls the voltage levels of the I2C, SPI and GPIO signals.

Because the SPI is already powered, you do not need to use the target power and target IO parameters. Using the same tools, Control Center Serial, Flash Center, or Promira API software, you can disable those voltage outputs.
Please note:
- When using the Control Center Serial Software, the default voltage level setting is 3.3V.
- The Flash Center Software does not control the GPIO pins.
- API Software allows you to create custom programs for your setup specifications.
We have two articles that provide examples about configuring the voltage levels and programming SPI Flash devices:
- Programming a Dual SPI Flash Using the Promira Serial Platform and the Control Center Serial Software.
- Programming an SPI Flash Using the Promira Serial Platform and the Control Center Serial Software.
Additional resources that you may find helpful:
- Promira Serial Platform Quick Start Guide
- Promira Serial Platform User Manual
- Control Center Serial Software User Manual
- Flash Center Software User Manual
- Promira API Documentation
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.