Module stm32h7xx_hal::xspi[−][src]

Expand description

Quad or Octo SPI bus

STM32H7 parts support either Quad or Octo SPI using dedicated peripheral(s).

Interface	Parts	# IO lines
Quad Spi	H742/743/750/753/747/757	1-bit, 2-bit or 4-bit
Octo Spi	H725/735/7a3/7b0/7b3	1-bit, 2-bit, 4-bit or 8-bit

Usage

This driver supports using the xSPI peripheral in indirect mode. This allows the peripheral to be used to read and write from an address over a SPI/QUADSPI/OCTOSPI interface.

The QUADSPI interface can be configured to operate on either of the two available banks.

use stm32h7xx_hal::xspi;

// Get the device peripherals and instantiate IO pins.
let dp = ...;
let (sck, io0, io1, io2, io3) = ...;

let mut qspi = dp.QUADSPI.bank1((sck, io0, io1, io2, io3), 3.mhz(), &ccdr.clocks,
                                ccdr.peripheral.QSPI);

// Configure QSPI to operate in 4-bit mode.
qspi.configure_mode(xspi::QspiMode::FourBit).unwrap();

// Write data to address 0x00 on the QSPI interface.
qspi.write(0x00, &[0xAB, 0xCD]).unwrap();

For OCTOSPI there are two peripherals, which can be initialised separately.

use stm32h7xx_hal::{xspi, xspi::OctospiWord as XW};

// Get the device peripherals and instantiate IO pins.
let dp = ...;
let _ = ...;

let mut octospi = dp.OCTOSPI1.octospi_unchecked(12.mhz(), &ccdr.clocks,
                                ccdr.peripheral.OCTOSPI1);

// Configure OCTOSPI to operate in 8-bit mode.
octospi.configure_mode(xspi::OctospiMode::EightBit).unwrap();

// Example RDID Read Indentification
let mut read: [u8; 3] = [0; 3];
octospi
    .read_extended(XW::U16(0x9F60), XW::U32(0), XW::None, 4, &mut read)
    .unwrap();

Configuration

A Config struct is used to configure the xSPI.

use stm32h7xx_hal::xspi;
let config = xspi::Config::new(12.mhz()).fifo_threshold(16);

Hyperbus

This driver supports a memory-mapped Hyperbus mode for the OCTOSPI peripheral.

let config = HyperbusConfig::new(80.mhz())
    .device_size_bytes(24) // 16 Mbyte
    .refresh_interval(4.us())
    .read_write_recovery(4) // 50ns
    .access_initial_latency(6);

let hyperram = dp.OCTOSPI1.octospi_hyperbus_unchecked(
    config,
    &ccdr.clocks,
    ccdr.peripheral.OCTOSPI1,
);

// Initialise and convert raw pointer to slice
let ram_ptr: *mut u32 = hyperram.init();
let ram = unsafe { slice::from_raw_parts_mut(ram_ptr, size_u32) };

Limitations

This driver currently only supports indirect operation mode of the xSPI interface. Automatic polling or memory-mapped modes are not supported, except for the OCTOSPI Hyperbus mode.

Using different operational modes (1-bit/2-bit/4-bit etc.) for different phases of a single transaction is not supported. It is possible to change operational mode between transactions by calling configure_mode.