Drive subsystem development

One 、GPIO And interrupt

The interface is introduced

wifiiot_gpio.h Interface

Its function is to initialize GPIO.

The interface name	function
GpioInit	initialization GPIO
GpioDeinit	Uninitialize GPIO
GpioSetDir	Set up GPIO Pin direction
GpioGetDir	obtain GPIO Pin direction
GpioSetOutputVal	Set up GPIO Pin output level value
GpioGetOutputVal	obtain GPIO Pin output level value

wifiiot_gpio_ex.h Interface
Its function is to set GPIO Tension and drive strength .

The interface name	function
IoSetPull	Set up GPIO Pin pull-up
IoGetPull	obtain GPIO Pin pull-up
IoSetFunc	Set up GPIO Pin function
IoGetFunc	obtain GPIO Pin function
IOSetDriverStrength	Set up GPIO Driving ability
IOGetDriverStrength	obtain GPIO Driving ability

see LED Corresponding GPIO Pin

LED Corresponding GPIO The pin is GPIO2 adopt control GPIO2 Output level signal to realize present LED The flicker of the lamp .

● When the power is high, it is on LED The lamp .

● Low power usually goes out LED The lamp .

GPIO interrupt

1.GPIO interrupt API Introduce wifiiot_gpio.h Interface profile :

wifiliot_gpio.h Contains a declaration GPIO Interrupt correlation function .

The interface name	function
GpioRegisterIsrFunc	Set up GPIO Pin interrupt function
GpioUnregisterIsrFunc	Cancel GPIO Pin interrupt function
GpioSetIsrMask	shielding GPIO Pin interrupt function
GpioSetIsrMode	Set up GPIO Pin interrupt trigger mode

2. Check the corresponding GPIO Pin

3. operation GPIO Lighten up LED

open “B2_basic_button" engineering button_example.c file , You can view and realize key control in the code LED Code of light on and off

Two 、PWM Subsystem development

API Introduce

How to change LED The brightness of the lamp

The configuration file

A total of two need to be modified hcs file , Namely ：device_info.hcs and pwm_config.hcs

1. First edit st\bearpi_hm_micro\liteos_a\hdf_config\device_info\device_info.hcs increase pwm node , This node should be in platform :: host Create under node . among policy=1 It means that the driver service is only released to the kernel ,moduleName It has to be for HDF_PLATFORM_PWM,serviceName Must be HDF_PLATFORM_PWM_ start , The following numbers are used to distinguish different pwm peripherals .

2. The second configuration file is created by yourself , stay \bearpi_hm_micro\liteos_a\hdf_config\ Record the creation pwm Catalog , Create... In the directory pwm_config.hcs, among PWM The counting frequency of is 1MHZ, Write dead in the code , You can modify ;physics_register Express TIM Register base address of , according to STM32MP1 Refer to the manual TIM2 The register address of is x40000000 The register address range is 0x70.

3、 ... and 、ADC Sampling development

The interface is introduced

Hardware design

software design

This function uses IoTAdcRead() Function to read ADC_CHANNEL_5 The value of is stored in data in , IOT_ADC_EQU_MODEL_8 Express 8 Sub average algorithm mode ,IOT_ADC_CUR_BAIS_DEFAULT Indicates the default automatic recognition mode , Finally through data * 1.8 * 4 / 4096.0 Calculate the actual voltage value .

Four 、I2C Bus

The interface is introduced

Check pin

Reading and writing NFC chip

5、 ... and 、UART Reading and writing

The interface is introduced

Check pin

Read and write data