I recently acquired the Promira Serial Platform with SPI Active - Level 3 Application for the (QSPI) features. Can you provide examples of configuring the Promira platform with the specifications of various QSPI devices, such as drive strength? The Promira platform will be used as a master device.
Response from Technical Support:Thank you for your question! There are two methods for configuring the Promira platform: writing XML scripts for the Control Center Serial Software application or executing Promira Software API I2C/SPI Active commands. Information about addressing parameters per specification and configuration guidelines are provided in the sections below.
Interfacing with QSPI Devices
Here are guidelines for interacting with slave devices:
Electrical Drive
The electrical drive strength of the Promira platform, such as driving eight slave devices simultaneously, is determined by its hardware capabilities. In this case, that would be the maximum current that the Promira platform pins can provide. For details, refer to Section 6 Electrical Specifications in the Promira Serial Platform I2C/SPI Active User Manual. Compare that information to the slave device requirements and ensure the total load is within those limits. Using the Promira platform beyond the specified ratings could cause damage, which would not be covered by warranty.
High-Impedance State
When the Promira platform is configured as an SPI master device, the slave select line (SS) is actively driven low. The MOSI, SCK, IO2, and IO3 lines are driven as appropriate for the SPI mode. After each transmission, these lines are released to a high-impedance (Hi-Z) state. To maintain clean signal levels when lines are idle, we recommend adding passive pull-up resistors, such as 100 kilo-ohms, on the MOSI and SCK line of each slave device. Note - This feature allows the Promira platform to reconnect to another SPI environment as a slave device without contention on the bus.
Configuration Guidelines for QSPI Devices
Two methods are available for configuring the Promira platform: the Control Center Serial Software or Promira API Software.
Configure QSPI Mode with Control Center Serial Software
Control Center Serial Software provides an easy start for developing a new script. Its GUI includes a Transaction log that allows users to view responses. Scripts can be created in XML files. After developing a functional script, especially for lengthy scripts and repeated commands, you can execute the same processes with API commands. For a detailed introduction to using this application, refer to Control Center Serial Software Series: Using I2C and SPI mode.
For your project, you can use the Multi I/O mode where you can specify the IO mode for bytes at different stages. For a detailed example, refer to this Knowledge Base article about programming Dual SPI Flash. Note - this article uses the Promira platform in Dual SPI mode. You can modify the setup as needed for Quad SPI mode.
Configure QSPI Mode with API Commands
The Promira API supports several operating systems and programming languages. Functional scripts are provided that can be used as-is or modified for your setup requirements.
We suggest looking at the spi_eeprom script, which is available within the Promira Software API package. This program performs simple SPI read and write operations to the Atmel AT25080A EEPROM found on the Total Phase I2C/SPI Activity Board. Note - you can modify this script for your QSPI chips. This script includes the command ps_queue_spi_write for queuing SPI master write. This API command writes a stream of words to the downstream SPI slave device taking in the selected SPI IO mode – in your case, PS_SPI_IO_QUAD will be one of the arguments to enter. (For other SPI modes, use PS_SPI_IO_STANDARD or PS_SPI_IO_DUAL.)
For more information about API commands, refer to Section 5 API Documentation of the Promira I2C/SPI Active User Manual.
Programming QSPI Devices
If you choose to use Flash Center Software for programming QSPI devices, refer to this article: Programming QSPI Flash Using the Promira Serial Platform and the Flash Center Software.
For configuring voltage and signal levels, we recommend this article: I Am Working with SPI Flash Devices of Various Signal Levels and Power Setups - How Do I Control the Voltage and Signal Levels of the GPIO and Power Supply Pins of the Promira Serial Platform?
We hope this answers your questions. Additional resources that you may find helpful include the following:
- Promira Serial Platform System User Manual
- Promira Serial Platform I2C/SPI Active User Manual
- Control Center Serial Software User Manual
- Flash Center Software User Manual
- SPI Background
- SPI Glossary
If you want more information, feel free to contact us with your questions, or request a demo that applies to your application.