HSLV example code?

[BDoon.1]

I am using a U585QI and have some external flash memory connected to an OCTOSPI. We are having some intermittent failures with it, and since we're powering the processor with 1.8v I want to try enabling HSLV for the Data/Clock lines. I found HAL_GPIO_EnableHighSPeedLowVoltage, but I'm not sure when to call it...

1) Is this a common use case for the high-speed-low-voltage functionality?

2) Is there any example code for this? Particularly the option bits aspect?

[Mohamed Aymen HZAMI]

Hello @Community member​ and welcome to the community,

You need to enable HSLV of OCTOSPI pins before initializing its pins.

Mohamed Aymen

[BDoon.1]

@Mohamed Aymen HZAMI​ Does that mean calling HAL_GPIO_EnableHighSPeedLowVoltage before HAL_OSPI_Init? And does it mean I need to do it to run OSPI from a 1.8v VDD reliably?

[Mohamed Aymen HZAMI]

Hello,

This is an example of OCTOSPI with HSLV configuration

/**
* @brief OSPI MSP Initialization
* This function configures the hardware resources used in this example
* @param hospi: OSPI handle pointer
* @retval None
*/
void HAL_OSPI_MspInit(OSPI_HandleTypeDef* hospi)
{
 GPIO_InitTypeDef GPIO_InitStruct = {0};
 RCC_PeriphCLKInitTypeDef PeriphClkInit = {0};
 if(hospi->Instance==OCTOSPI1)
 {
 /* USER CODE BEGIN OCTOSPI1_MspInit 0 */
 HAL_GPIO_EnableHighSPeedLowVoltage(OCTOSPI_CS_GPIO_PORT, OCTOSPI_CS_PIN);
 HAL_GPIO_EnableHighSPeedLowVoltage(OCTOSPI_DQS0_GPIO_PORT, OCTOSPI_DQS0_PIN);
 HAL_GPIO_EnableHighSPeedLowVoltage(OCTOSPI_DQS1_GPIO_PORT, OCTOSPI_DQS1_PIN);
 HAL_GPIO_EnableHighSPeedLowVoltage(OCTOSPI_CLK_GPIO_PORT, OCTOSPI_CLK_PIN);
 HAL_GPIO_EnableHighSPeedLowVoltage(OCTOSPI_NCLK_GPIO_PORT, OCTOSPI_NCLK_PIN);
 
 HAL_GPIO_EnableHighSPeedLowVoltage(OCTOSPI_D0_GPIO_PORT, OCTOSPI_D0_PIN);
 HAL_GPIO_EnableHighSPeedLowVoltage(OCTOSPI_D1_GPIO_PORT, OCTOSPI_D1_PIN);
 HAL_GPIO_EnableHighSPeedLowVoltage(OCTOSPI_D2_GPIO_PORT, OCTOSPI_D2_PIN);
 HAL_GPIO_EnableHighSPeedLowVoltage(OCTOSPI_D3_GPIO_PORT, OCTOSPI_D3_PIN);
 HAL_GPIO_EnableHighSPeedLowVoltage(OCTOSPI_D4_GPIO_PORT, OCTOSPI_D4_PIN);
 HAL_GPIO_EnableHighSPeedLowVoltage(OCTOSPI_D5_GPIO_PORT, OCTOSPI_D5_PIN);
 HAL_GPIO_EnableHighSPeedLowVoltage(OCTOSPI_D6_GPIO_PORT, OCTOSPI_D6_PIN);
 HAL_GPIO_EnableHighSPeedLowVoltage(OCTOSPI_D7_GPIO_PORT, OCTOSPI_D7_PIN);
 
 /* USER CODE END OCTOSPI1_MspInit 0 */
 
 /** Initializes the peripherals clock
 */
 PeriphClkInit.PeriphClockSelection = RCC_PERIPHCLK_OSPI;
 PeriphClkInit.OspiClockSelection = RCC_OSPICLKSOURCE_SYSCLK;
 if (HAL_RCCEx_PeriphCLKConfig(&PeriphClkInit) != HAL_OK)
 {
 Error_Handler();
 }
 
 /* Peripheral clock enable */
 __HAL_RCC_OSPIM_CLK_ENABLE();
 __HAL_RCC_OSPI1_CLK_ENABLE();
 
 __HAL_RCC_GPIOC_CLK_ENABLE();
 __HAL_RCC_GPIOA_CLK_ENABLE();
 __HAL_RCC_GPIOB_CLK_ENABLE();
 /**OCTOSPI1 GPIO Configuration
 PC0 ------> OCTOSPIM_P1_IO7
 PC1 ------> OCTOSPIM_P1_IO4
 PC2 ------> OCTOSPIM_P1_IO5
 PA7 ------> OCTOSPIM_P1_IO2
 PC3 ------> OCTOSPIM_P1_IO6
 PB0 ------> OCTOSPIM_P1_IO1
 PB2 ------> OCTOSPIM_P1_DQS
 PA2 ------> OCTOSPIM_P1_NCS
 PA3 ------> OCTOSPIM_P1_CLK
 PA6 ------> OCTOSPIM_P1_IO3
 PB1 ------> OCTOSPIM_P1_IO0
 */
 GPIO_InitStruct.Pin = GPIO_PIN_0;
 GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
 GPIO_InitStruct.Pull = GPIO_NOPULL;
 GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
 GPIO_InitStruct.Alternate = GPIO_AF3_OCTOSPI1;
 HAL_GPIO_Init(GPIOC, &GPIO_InitStruct);
 
 GPIO_InitStruct.Pin = GPIO_PIN_1|GPIO_PIN_2|GPIO_PIN_3;
 GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
 GPIO_InitStruct.Pull = GPIO_NOPULL;
 GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
 GPIO_InitStruct.Alternate = GPIO_AF10_OCTOSPI1;
 HAL_GPIO_Init(GPIOC, &GPIO_InitStruct);
 
 GPIO_InitStruct.Pin = GPIO_PIN_7|GPIO_PIN_2|GPIO_PIN_3|GPIO_PIN_6;
 GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
 GPIO_InitStruct.Pull = GPIO_NOPULL;
 GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
 GPIO_InitStruct.Alternate = GPIO_AF10_OCTOSPI1;
 HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
 
 GPIO_InitStruct.Pin = GPIO_PIN_0|GPIO_PIN_2|GPIO_PIN_1;
 GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
 GPIO_InitStruct.Pull = GPIO_NOPULL;
 GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
 GPIO_InitStruct.Alternate = GPIO_AF10_OCTOSPI1;
 HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);
 
 /* USER CODE BEGIN OCTOSPI1_MspInit 1 */
 
 /* USER CODE END OCTOSPI1_MspInit 1 */
 }
 
}

The High speed low voltage (HSLV) is a feature, when enabled it allow the GPIOs to reach higher frequencies. The only constraint is that Vdd must not exceed 2.5v (Vdd < 2.5v)

Mohamed Aymen

[BDoon.1]

Awesome, thank you! Can you confirm that this is something I should be doing to get reliable OSPI communication when powered at 1.8v?

[Mohamed Aymen HZAMI]

Hello @Community member​,

If you are targeting higher frequencies at Vdd < 2.5V, yes it is recommended to Enable the HSLV.

Mohamed Aymen