Setting gpio ports as outputs and setting them to Vdd

[Benjamin Willis]

I am trying to configure two ports as outputs, setting them to Vdd and toggling them. The two ports in question are Po.06 and Po.07.

Here is my code to configure these ports as outputs, set them, then toggle each periodically.

#include "nrf_gpio.h"
#include "nrf_delay.h"


void init_leds(void)
{
	// initialize ports to be outputs
	nrf_gpio_cfg_output(7);
	nrf_delay_ms(1);
	nrf_gpio_cfg_output(6);
	nrf_delay_ms(1);
	// then activate the leds
	nrf_gpio_pin_set(6);
	nrf_delay_ms(1);
	nrf_gpio_pin_set(7);
	nrf_delay_ms(1);

}

void toggle_red_led(void)
{
	nrf_gpio_pin_toggle(7);
}

void toggle_white_led(void)
{
	nrf_gpio_pin_toggle(6);
}

void init_board(void)
{
	init_leds();
}


int main(void)
{
    init_board();
    for(;;)
    {
        toggle_red_led(void);
        nrf_delay_ms(500);
        toggle_white_led(void);
        nrf_delay_ms(500);
    }
}

 

Here is the board configuration file, pca10040.h:

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 *    such product, must reproduce the above copyright notice, this list of
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 *    software without specific prior written permission.
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 *    Nordic Semiconductor ASA integrated circuit.
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 */
#ifndef PCA10040_H
#define PCA10040_H

#ifdef __cplusplus
extern "C" {
#endif

#include "nrf_gpio.h"


#define LEDS_NUMBER 		2
#define LED_START      6
#define LED_1          6
#define LED_2          7
#define LED_STOP       7

#define LEDS_LIST { LED_1, LED_2 }

#define BSP_LED_0      LED_1
#define BSP_LED_1      LED_2


#define LEDS_ACTIVE_STATE 0

#define LEDS_INV_MASK  LEDS_MASK

#define BUTTONS_NUMBER 0
#define BUTTONS_ACTIVE_STATE 0

#define RX_PIN_NUMBER  0
#define TX_PIN_NUMBER  1
#define CTS_PIN_NUMBER 8
#define RTS_PIN_NUMBER 9
#define HWFC           true

#define SPIS_MISO_PIN   24  // SPI MISO signal.
#define SPIS_CSN_PIN    16  // SPI CSN signal.
#define SPIS_MOSI_PIN   22  // SPI MOSI signal.
#define SPIS_SCK_PIN    23  // SPI SCK signal.

#define SPIM0_SCK_PIN   29  // SPI clock GPIO pin number.
#define SPIM0_MOSI_PIN  25  // SPI Master Out Slave In GPIO pin number.
#define SPIM0_MISO_PIN  28  // SPI Master In Slave Out GPIO pin number.
#define SPIM0_SS_PIN    12  // SPI Slave Select GPIO pin number.

#define SPIM1_SCK_PIN   2   // SPI clock GPIO pin number.
#define SPIM1_MOSI_PIN  3   // SPI Master Out Slave In GPIO pin number.
#define SPIM1_MISO_PIN  4   // SPI Master In Slave Out GPIO pin number.
#define SPIM1_SS_PIN    5   // SPI Slave Select GPIO pin number.

#define SPIM2_SCK_PIN   12  // SPI clock GPIO pin number.
#define SPIM2_MOSI_PIN  13  // SPI Master Out Slave In GPIO pin number.
#define SPIM2_MISO_PIN  14  // SPI Master In Slave Out GPIO pin number.
#define SPIM2_SS_PIN    15  // SPI Slave Select GPIO pin number.

// serialization APPLICATION board - temp. setup for running serialized MEMU tests
#define SER_APP_RX_PIN              23    // UART RX pin number.
#define SER_APP_TX_PIN              24    // UART TX pin number.
#define SER_APP_CTS_PIN             2     // UART Clear To Send pin number.
#define SER_APP_RTS_PIN             25    // UART Request To Send pin number.

#define SER_APP_SPIM0_SCK_PIN       27     // SPI clock GPIO pin number.
#define SER_APP_SPIM0_MOSI_PIN      2      // SPI Master Out Slave In GPIO pin number
#define SER_APP_SPIM0_MISO_PIN      26     // SPI Master In Slave Out GPIO pin number
#define SER_APP_SPIM0_SS_PIN        23     // SPI Slave Select GPIO pin number
#define SER_APP_SPIM0_RDY_PIN       25     // SPI READY GPIO pin number
#define SER_APP_SPIM0_REQ_PIN       24     // SPI REQUEST GPIO pin number

// serialization CONNECTIVITY board
#define SER_CON_RX_PIN              24    // UART RX pin number.
#define SER_CON_TX_PIN              23    // UART TX pin number.
#define SER_CON_CTS_PIN             25    // UART Clear To Send pin number. Not used if HWFC is set to false.
#define SER_CON_RTS_PIN             2     // UART Request To Send pin number. Not used if HWFC is set to false.


#define SER_CON_SPIS_SCK_PIN        27    // SPI SCK signal.
#define SER_CON_SPIS_MOSI_PIN       2     // SPI MOSI signal.
#define SER_CON_SPIS_MISO_PIN       26    // SPI MISO signal.
#define SER_CON_SPIS_CSN_PIN        23    // SPI CSN signal.
#define SER_CON_SPIS_RDY_PIN        25    // SPI READY GPIO pin number.
#define SER_CON_SPIS_REQ_PIN        24    // SPI REQUEST GPIO pin number.

#define SER_CONN_CHIP_RESET_PIN     11    // Pin used to reset connectivity chip


// Arduino board mappings
#define ARDUINO_SCL_PIN             27    // SCL signal pin
#define ARDUINO_SDA_PIN             26    // SDA signal pin
#define ARDUINO_AREF_PIN            2     // Aref pin
#define ARDUINO_13_PIN              25    // Digital pin 13
#define ARDUINO_12_PIN              24    // Digital pin 12
#define ARDUINO_11_PIN              23    // Digital pin 11
#define ARDUINO_10_PIN              22    // Digital pin 10
#define ARDUINO_9_PIN               20    // Digital pin 9
#define ARDUINO_8_PIN               19    // Digital pin 8

#define ARDUINO_7_PIN               18    // Digital pin 7
#define ARDUINO_6_PIN               17    // Digital pin 6
#define ARDUINO_5_PIN               16    // Digital pin 5
#define ARDUINO_4_PIN               15    // Digital pin 4
#define ARDUINO_3_PIN               14    // Digital pin 3
#define ARDUINO_2_PIN               13    // Digital pin 2
#define ARDUINO_1_PIN               12    // Digital pin 1
#define ARDUINO_0_PIN               11    // Digital pin 0

#define ARDUINO_A0_PIN              3     // Analog channel 0
#define ARDUINO_A1_PIN              4     // Analog channel 1
#define ARDUINO_A2_PIN              28    // Analog channel 2
#define ARDUINO_A3_PIN              29    // Analog channel 3
#define ARDUINO_A4_PIN              30    // Analog channel 4
#define ARDUINO_A5_PIN              31    // Analog channel 5


#ifdef __cplusplus
}
#endif

#endif // PCA10040_H

The problem is that port 7 is toggling but port 6 does not. After probing the port with a DMM and watching its noisy voltage go from 1mV to 15mV, I assumed that port 6 was floating still. Is there a configuration file somewhere that is preventing port six from becoming an output and toggling? Is there anywhere I can look for an error message?

Using nRF52832, SDK15.0.0, SD132, Keil uVision 5, compiler set to Level 2 optimization.

Thank you for your time.

[Vidar Berg]

Hi,

I don't see anything in your code that can override the IO configuration (SPI,TWI,etc). Do you know what the max. sink/source current in your case, and is it the same for both LEDs? If needed, you can change the drive strength in the GPIO pin configuration (GPIO spec.)

[Benjamin Willis]

I have made sure to set the SPI and TWI pins away from Po.06 and Po.07, so that's not an issue. The two pins 6 & 7 are actually controlling the gates of MOSFETs, and those MOSFETs get their power from the bus. The MOSFETs are essentially on/off switches for the LEDs. So it's not a current issue either. 

[Vidar Berg]

I don't think the issue is related to your FW code then. You may program attached .hex file if you want to confirm the behavior with a different FW image.  It toggles pin 6 and 7 at 1 s interval using SW delays like you did in your code. I've tested it on a DK. 

nrfjprog --program pin_toggle_w_softdevice.hex --chiperase -r

pin_toggle_w_softdevice.hex

Do you have more than one board to test this on? In case it is a hw issue.

[Benjamin Willis]

Sorry for being absent for so long. The image that you provided gives me the same result that I was getting with my own code above. Also, I have tested on two different boards with identical design, and they all behave identically. So I think that's enough to conclude that the hardware is the issue. Thank you for your help!