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GPIO improvements #4

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Merged
evoggy merged 2 commits into from
Nov 24, 2025
Merged

GPIO improvements #4

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3d80204
Improve GPIO read/set
evoggy Nov 19, 2025
236dd30
removed comments
evoggy Nov 19, 2025
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78 changes: 35 additions & 43 deletions Core/Src/module/gpio.c
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Original file line number Diff line number Diff line change
Expand Up @@ -56,12 +56,14 @@ static gpio_entry_t gpio_map[] = {

// Cache for GPIO direction (1=output, 0=input)
static uint16_t gpio_direction_cache = 0x0000; // Initialize all as inputs
static uint16_t gpio_data_cache = 0x0000; // Cache for GPIO output data

void gpio_module_init(void)
{
// GPIO clocks are already enabled in main.c
// Initialize all GPIOs as inputs
gpio_direction_cache = 0x0000;
gpio_data_cache = 0;

// Configure all pins as inputs
for (uint8_t i = 0; i < sizeof(gpio_map) / sizeof(gpio_entry_t); i++) {
Expand Down Expand Up @@ -99,7 +101,18 @@ uint8_t gpio_module_read(uint16_t address)
for (uint8_t i = 0; i < 8; i++) {
if (gpio_index < sizeof(gpio_map) / sizeof(gpio_entry_t))
{
if (HAL_GPIO_ReadPin(gpio_map[gpio_index].port, gpio_map[gpio_index].pin) == GPIO_PIN_SET)
uint8_t is_output = (gpio_direction_cache >> gpio_index) & 0x01;
GPIO_PinState pin_state;

if (is_output) {
// If pin is output, read the output we've set before
pin_state = ((gpio_data_cache >> gpio_index) & 0x01) ? GPIO_PIN_SET : GPIO_PIN_RESET;
} else {
// If pin is input, read the actual pin state
pin_state = HAL_GPIO_ReadPin(gpio_map[gpio_index].port, gpio_map[gpio_index].pin);
}

if (pin_state == GPIO_PIN_SET)
{
result |= (1 << i);
}
Expand All @@ -120,7 +133,6 @@ void gpio_module_write(uint16_t address, uint8_t value)
{
// Write to GPIO direction and update cache
uint8_t gpio_addr = (uint8_t)(address - GPIO_DIR_START);
uint8_t gpio_index = gpio_addr == 0 ? 0 : 8; // Start at 8 if it's the high byte

// Update the cache
if (gpio_addr == 0) {
Expand All @@ -129,55 +141,35 @@ void gpio_module_write(uint16_t address, uint8_t value)
gpio_direction_cache = (gpio_direction_cache & 0x00FF) | ((uint16_t)value << 8); // Update high byte
}

for (uint8_t i = 0; i < 8; i++) {
if (gpio_index < sizeof(gpio_map) / sizeof(gpio_entry_t))
{
uint8_t gpio_dir = (value >> i) & 0x01;

if (gpio_dir == 1)
{
GPIO_InitTypeDef GPIO_InitStruct;
GPIO_InitStruct.Pin = gpio_map[gpio_index].pin;
GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
GPIO_InitStruct.Pull = GPIO_NOPULL;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
HAL_GPIO_Init(gpio_map[gpio_index].port, &GPIO_InitStruct);
}
else
{
GPIO_InitTypeDef GPIO_InitStruct;
GPIO_InitStruct.Pin = gpio_map[gpio_index].pin;
GPIO_InitStruct.Mode = GPIO_MODE_INPUT;
GPIO_InitStruct.Pull = GPIO_NOPULL;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
HAL_GPIO_Init(gpio_map[gpio_index].port, &GPIO_InitStruct);
}
}
gpio_index++;
for (uint8_t gpio_index = 0; gpio_index < sizeof(gpio_map) / sizeof(gpio_entry_t); gpio_index++) {
uint8_t gpio_dir = (gpio_direction_cache >> gpio_index) & 0x01;
GPIO_InitTypeDef GPIO_InitStruct;
GPIO_InitStruct.Pin = gpio_map[gpio_index].pin;
GPIO_InitStruct.Mode = gpio_dir ? GPIO_MODE_OUTPUT_PP : GPIO_MODE_INPUT;
GPIO_InitStruct.Pull = GPIO_NOPULL;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
HAL_GPIO_Init(gpio_map[gpio_index].port, &GPIO_InitStruct);
}
}

if (address >= GPIO_DATA_START && address <= GPIO_DATA_END)
{
// Write to GPIO data
uint8_t gpio_addr = (uint8_t)(address - GPIO_DATA_START);
uint8_t gpio_index = gpio_addr == 0 ? 0 : 8; // Start at 8 if it's the high byte

for (uint8_t i = 0; i < 8; i++) {
if (gpio_index < sizeof(gpio_map) / sizeof(gpio_entry_t))
{
uint8_t gpio_value = (value >> i) & 0x01;

if (gpio_value == 1)
{
HAL_GPIO_WritePin(gpio_map[gpio_index].port, gpio_map[gpio_index].pin, GPIO_PIN_SET);
}
else
{
HAL_GPIO_WritePin(gpio_map[gpio_index].port, gpio_map[gpio_index].pin, GPIO_PIN_RESET);
}
}
gpio_index++;
// Update the cache
if (gpio_addr == 0) {
gpio_data_cache = (gpio_data_cache & 0xFF00) | value; // Update low byte
} else {
gpio_data_cache = (gpio_data_cache & 0x00FF) | ((uint16_t)value << 8); // Update high byte
}

for (uint8_t gpio_index = 0; gpio_index < sizeof(gpio_map) / sizeof(gpio_entry_t); gpio_index++) {
uint8_t is_output = (gpio_direction_cache >> gpio_index) & 0x01;
if (is_output) {
uint8_t gpio_value = (gpio_data_cache >> gpio_index) & 0x01;
HAL_GPIO_WritePin(gpio_map[gpio_index].port, gpio_map[gpio_index].pin, gpio_value == 1 ? GPIO_PIN_SET : GPIO_PIN_RESET);
}
}
}
}