How to set the vdd level

[helen]

Hi

         How to set the vdd level to 3.3v when the system is in the High Voltage mode?I can't fine any api about setting vdd level in document.

[Simonr]

Hi

The output voltage from REG0 is set with the UICR_REGOUT0 register in the nrf52833_bitfields.h header file in the MDK 

/* Register: UICR_REGOUT0 */
/* Description: Output voltage from REG0 regulator stage. The maximum output voltage from this stage is given as VDDH - V_VDDH-VDD. */

/* Bits 2..0 : Output voltage from REG0 regulator stage. */
#define UICR_REGOUT0_VOUT_Pos (0UL) /*!< Position of VOUT field. */
#define UICR_REGOUT0_VOUT_Msk (0x7UL << UICR_REGOUT0_VOUT_Pos) /*!< Bit mask of VOUT field. */
#define UICR_REGOUT0_VOUT_1V8 (0UL) /*!< 1.8 V */
#define UICR_REGOUT0_VOUT_2V1 (1UL) /*!< 2.1 V */
#define UICR_REGOUT0_VOUT_2V4 (2UL) /*!< 2.4 V */
#define UICR_REGOUT0_VOUT_2V7 (3UL) /*!< 2.7 V */
#define UICR_REGOUT0_VOUT_3V0 (4UL) /*!< 3.0 V */
#define UICR_REGOUT0_VOUT_3V3 (5UL) /*!< 3.3 V */
#define UICR_REGOUT0_VOUT_DEFAULT (7UL) /*!< Default voltage: 1.8 V */

Best regards,

Simon

[helen]

Hi

        I use SES,How to set in SES,Thanks.

[Simonr]

Hi

You can do something similar to the gpio_output_voltage_setup() function in boards.c as part of your main application, and that should set the GPIO output voltage to 3.0V.

/**
 * Function for configuring UICR_REGOUT0 register
 * to set GPIO output voltage to 3.0V.
 */
static void gpio_output_voltage_setup(void)
{
    // Configure UICR_REGOUT0 register only if it is set to default value.
    if ((NRF_UICR->REGOUT0 & UICR_REGOUT0_VOUT_Msk) ==
        (UICR_REGOUT0_VOUT_DEFAULT << UICR_REGOUT0_VOUT_Pos))
    {
        NRF_NVMC->CONFIG = NVMC_CONFIG_WEN_Wen;
        while (NRF_NVMC->READY == NVMC_READY_READY_Busy){}

        NRF_UICR->REGOUT0 = (NRF_UICR->REGOUT0 & ~((uint32_t)UICR_REGOUT0_VOUT_Msk)) |
                            (UICR_REGOUT0_VOUT_3V0 << UICR_REGOUT0_VOUT_Pos);

        NRF_NVMC->CONFIG = NVMC_CONFIG_WEN_Ren;
        while (NRF_NVMC->READY == NVMC_READY_READY_Busy){}

        // System reset is needed to update UICR registers.
        NVIC_SystemReset();
    }
}

Best regards,

Simon