Enhanced General-Purpose Input/Output (EGPIO) Appendix#

This appendix defines terminology, acronyms, use cases, and sample code for working with general-purpose input/output (GPIO) on SiWx917 microcontrollers and system-on-chip (SoC) devices. It provides reference definitions, domain explanations, and practical examples for implementing and debugging GPIO configurations in both high-performance (HP) and ultra-low-power (ULP) domains, including ultra-ultra-low-power (UULP) operation.

Glossary#

Acronyms#

Extended Examples#

The following examples demonstrate common GPIO configurations and interrupt-driven scenarios:

• sl_si91x_gpio_detailed_example – Basic GPIO input/output and LED toggle in an HP domain.

• sl_si91x_gpio_example – Configures GPIO interrupt and toggles an HP GPIO.

• sl_si91x_gpio_group_example – Demonstrates multi-pin group interrupts.

• sl_si91x_gpio_ulp_example – Toggles ULP GPIO and configures a ULP pin interrupt.

• sl_si91x_gpio_uulp_example – Configures an interrupt in UULP domain.

• sl_si91x_ulp_gpio – Demonstrates ULP GPIO state transitions between PS4 and PS2.

Usage Scenarios and Code Snippets#

Scenario 1. Toggling an LED (HP GPIO)#

#include "sl_si91x_driver_gpio.h"
#include "rsi_debug.h"

#define LED_PORT SL_SI91X_GPIO_6_PORT
#define LED_PIN  GPIO_PIN_NUMBER6

static sl_si91x_gpio_pin_config_t led_pin_config = {{LED_PORT, LED_PIN}, GPIO_OUTPUT};

void gpio_led_init(void) {
  sl_status_t status = sl_gpio_driver_init();
  if (status != SL_STATUS_OK) return;
  sl_gpio_set_configuration(led_pin_config);
}

void gpio_led_toggle(void) {
  sl_gpio_driver_toggle_pin(&led_pin_config.port_pin);
}

Scenario 2. Button Interrupt Handling (HP GPIO)#

#include "sl_si91x_driver_gpio.h"

#define BUTTON_PORT SL_SI91X_GPIO_11_PORT
#define BUTTON_PIN  GPIO_PIN_NUMBER11

void button_callback(uint32_t intr) {
  if (intr == PIN_INTR_0) {
    printf("Button press detected!\n");
  }
}

void button_init(void) {
  sl_si91x_gpio_pin_config_t button_config = {{BUTTON_PORT, BUTTON_PIN}, GPIO_INPUT};
  sl_gpio_set_configuration(button_config);
  sl_gpio_driver_configure_interrupt(&button_config.port_pin, 0, SL_GPIO_INTERRUPT_RISE_EDGE, button_callback, 0);
}

Scenario 3. Button Interrupt Handling (ULP GPIO)#

#include "sl_si91x_driver_gpio.h"

#define BUTTON_PORT SL_SI91X_ULP_GPIO_11_PORT
#define BUTTON_PIN  SL_SI91X_ULP_GPIO_11_PIN

void ulp_button_callback(uint32_t intr) {
  if (intr == ULP_PIN_INTR_0) {
    printf("ULP Button interrupt triggered\n");
  }
}

void ulp_button_init(void) {
  sl_si91x_gpio_pin_config_t ulp_button_config = {{BUTTON_PORT, BUTTON_PIN}, GPIO_INPUT};
  sl_gpio_set_configuration(ulp_button_config);
  sl_gpio_driver_configure_interrupt(&ulp_button_config.port_pin, 0, SL_GPIO_INTERRUPT_RISE_EDGE, ulp_button_callback, 0);
}

Scenario 4. Group Interrupt Example (HP and ULP GPIO)#

#include "sl_si91x_driver_gpio.h"

#define PIN_COUNT  2

sl_si91x_gpio_pin_config_t hp_pins[PIN_COUNT] = {
  {{SL_SI91X_GPIO_8_PORT, GPIO_PIN_NUMBER8}, GPIO_INPUT},
  {{SL_SI91X_GPIO_9_PORT, GPIO_PIN_NUMBER9}, GPIO_INPUT}
};

sl_si91x_gpio_group_interrupt_config_t group_config;

void group_callback(uint32_t grp_intr) {
  if (grp_intr == GROUP_INT_1) {
    printf("Group interrupt triggered\n");
  }
}

void group_init(void) {
  sl_gpio_driver_init();
  for (int i = 0; i < PIN_COUNT; i++) sl_gpio_set_configuration(hp_pins[i]);
  group_config.grp_interrupt = GROUP_INT_1;
  group_config.grp_interrupt_cnt = PIN_COUNT;
  group_config.and_or = GPIO_AND;
  group_config.level_edge = GPIO_LEVEL;
  sl_si91x_gpio_driver_configure_group_interrupt(&group_config, group_callback);
}

Reference#

FAQ#

Q1: What’s the difference between HP, ULP, and UULP GPIOs?

• HP GPIOs operate in active mode for performance-critical tasks.

• ULP GPIOs function in deep-sleep and low-power states.

• UULP GPIOs remain active in the lowest power states with minimal leakage.

Q2: How should GPIOs be configured before sleep?

• Set outputs to safe states.

• Enable pull-ups or pull-down resistors as needed.

• Disable unused interrupts.

• Save configuration if necessary.

Q3: How do I recover from undefined GPIO states?

sl_gpio_driver_deinit();
sl_gpio_driver_init();

Q4: What are some common GPIO error codes?

Q5: How can I debug GPIO issues?

• Probe signal transitions with a logic analyzer.

• Check pad configuration (pulls, drive strength).

• Confirm pinmux settings for multifunction pins.

• Use the Energy Profiler in Simplicity Studio to verify wake behavior.