IRTX

This section introduces the Infrared Transmitter(IRTX) APIs including terms and acronyms, supported features, software architecture, details on how to use this driver, IRTX function groups, enums, structures and functions. More...

Overview

This section introduces the Infrared Transmitter(IRTX) APIs including terms and acronyms, supported features, software architecture, details on how to use this driver, IRTX function groups, enums, structures and functions.

Terms and acronyms

The following provides descriptions to the terms commonly used in the IRTX driver and how to use its various functions.

Terms	Details
IRTX	Infrared Transmitter is the transmitter element to send infrared radiation. For more information, please refer to introduction to IrDA in Wikipedia .

Supported features

• Support NEC, RC5, RC6 and PWD modes.
  Has four encoding modes:
• The NEC mode: The NEC encoding format is one of the widely used infrared protocols. In this mode, the NEC encoded code can be directly sent by the hardware.
• The PWD mode: PWD is Pulse width detection(PWD). In this mode, any type of code transmitted by infrared radiation can be sent. The transmitted content can be determined using the wavelength.
• The RC5 mode: The Philips RC5 IR transmission protocol uses Manchester encoding of the message bits. In this mode, the RC5 encoded code can be directly sent by the hardware.
• The RC6 mode: Similar to the RC-5 the new RC-6 protocol was also defined by Philips. In this mode, the RC6 encoded code can be directly sent by the hardware.

How to use this driver

• Use IRTX in the NEC/RC5/RC6 mode, Maximum transfer size is 12 Bytes.
  
  • Step1: Call hal_gpio_init() to init the pins, if EPT tool hasn't been used to configure the related pinmux.
  • Step2: Set GPIO33 to TX function to enable the IRTX mode.
  • Step3: Call hal_irtx_init() to initialize the IRTX.
  • Step4: start the hardware in NEC/RC5/RC6 mode if use NEC mode:Call hal_irtx_send_nec_data() to start the hardware. if use RC5 mode:Call hal_irtx_send_rc5_data() to start the hardware. if use RC6 mode:Call hal_irtx_send_rc6_data() to start the hardware.
  • Step5: Call hal_irtx_deinit() to deinitialize the IRTX.
  • Sample code:

      //Init GPIO, set GPIO pinmux(if EPT tool hasn't been used to configure the related pinmux).
      hal_gpio_init(HAL_GPIO_33);
    
      //Call hal_pinmux_set_function() to set GPIO pinmux, for more information, please reference hal_pinmux_define.h
      //function_index = HAL_GPIO_33_IR_TX.Need not to configure pinmux if EPT tool is used.
      hal_pinmux_set_function(HAL_GPIO_33, function_index);//Set the GPIO33 to IRTX mode.
    
      hal_irtx_init();
      uint8_t data[HAL_IRTX_MAX_DATA_LENGTH] = {
          0xA5, 0xF0, 0xAF, 0x00,
          0xff, 0x00, 0xAA, 0x55
      };
    
      //If use NEC mode:  hal_irtx_send_nec_data(HAL_IRTX_REPEAT_DISABLE,data, 64)
      //If use RC5 mode:  hal_irtx_send_rc5_data(HAL_IRTX_REPEAT_DISABLE,data, 64)
      //If use RC6 mode:  hal_irtx_send_rc6_data(HAL_IRTX_REPEAT_DISABLE,data, 64)
      if (HAL_IRTX_STATUS_OK != hal_irtx_send_nec_data(HAL_IRTX_REPEAT_DISABLE,
                                                data, 64)) {     //Use HAL_IRTX_REPEAT_ENABLE to send the data continuously.
          printf("hal_irtx_send_nec_data fail.\r\n");
    
      }
    hal_irtx_deinit();

• Use IRTX in the PWD mode, Maximum transfer size is 68 Bytes.
  
  • Step1: Call hal_gpio_init() to init the pins, if EPT tool hasn't been used to configure the related pinmux.
  • Step2: Set GPIO33 to TX function to enable the IRTX mode.
  • Step3: Call hal_irtx_init() to initialize the IRTX.
  • Step4: Call hal_irtx_register_pulse_data_callback() to register callback function.
  • Step5: Call hal_irtx_configure_pulse_data_carrier() to set frequency and duty_cycle.
  • Step6: Call hal_irtx_send_pulse_data() to send data.
  • Step7: Call hal_irtx_deinit() to de-initialize the IRTX.
  • Sample code:

     static void isr_ir_tx(void *arg)
     {
         ir_tx_done = 1;
     }
    
     uint8_t data_number = 41;
     uint8_t data[68] = {
         225, 112, 17, 15, 34, 15, 35, 15, 17, 15, 34, 15, 17, 15, 17, 15,
         17, 15, 34, 15, 17, 15, 34, 15, 34, 15, 17, 15, 34, 15, 17, 15,
         17, 15, 17, 15, 34, 15, 34, 15, 34
     };
    
     //Init GPIO, set GPIO pinmux(if EPT tool hasn't been used to configure the related pinmux).
     hal_gpio_init(HAL_GPIO_33);
    
     //Call hal_pinmux_set_function() to set GPIO pinmux, for more information, please reference hal_pinmux_define.h
     //function_index = HAL_GPIO_33_IR_TX.Need not to configure pinmux if EPT tool is used.
     hal_pinmux_set_function(HAL_GPIO_33, function_index);//Set the GPIO33 to IRTX mode.
    
     hal_irtx_init();
     printf("output Software Pluse Width IR \r\n");
     if (HAL_IRTX_STATUS_OK != hal_irtx_register_pulse_data_callback(isr_ir_tx, NULL)) {
         printf("hal_irtx_send_pulse_data failed.\r\n");
         return;
     }
    
     uint16_t frequency = 40;//40KHz
     uint8_t duty_cycle = 25;// 25% duty cycle
     if (HAL_IRTX_STATUS_OK != hal_irtx_configure_pulse_data_carrier(frequency, duty_cycle)) {
         printf("hal_irtx_send_pulse_data failed.\r\n");
         return;
     }
    
     uint8_t base_period = 80; // unit:0.5us, SWM_BP=80, PW_value saturates for one cycle of the NEC leading code with duration of 9ms (high) and 4.5ms(low).
     if (HAL_IRTX_STATUS_OK != hal_irtx_send_pulse_data(base_period, data, data_number)) {
         printf("hal_irtx_send_pulse_data failed.\r\n");
         return;    }
    
     while (!ir_tx_done) {
     }//Wait for an interrupt
    hal_irtx_deinit();

Functions
hal_irtx_status_t	hal_irtx_init (void)
	This function initializes the IRTX hardware clock. More...
hal_irtx_status_t	hal_irtx_deinit (void)
	This function deinitializes the IRTX hardware clock. More...
hal_irtx_status_t	hal_irtx_send_nec_data (hal_irtx_repeat_code_t repeat_code, const uint8_t data[(12)], uint32_t bit_length)
	This function sends the data in the NEC encoding format. More...
hal_irtx_status_t	hal_irtx_send_rc5_data (hal_irtx_repeat_code_t repeat_code, const uint8_t data[(12)], uint32_t bit_length)
	This function sends the data in the RC5 encoding format. More...
hal_irtx_status_t	hal_irtx_send_rc6_data (hal_irtx_repeat_code_t repeat_code, const uint8_t data[(12)], uint32_t bit_length)
	This function sends the data in the RC6 encoding format. More...
hal_irtx_status_t	hal_irtx_configure_pulse_data_carrier (uint32_t frequency, uint32_t duty_cycle)
	This function configures the pulse data carrier. More...
hal_irtx_status_t	hal_irtx_register_pulse_data_callback (hal_irtx_pulse_data_callback_t callback, void *user_data)
	This function registers the PWD encoding format data callback. More...
hal_irtx_status_t	hal_irtx_send_pulse_data (uint32_t base_period, uint8_t *data, uint32_t length)
	This function sends the data in the PWD encoded format. More...
hal_irtx_status_t	hal_irtx_get_running_status (hal_irtx_running_status_t *running_status)
	This function gets the current state of the IRTX. More...

Modules
	Define
	Enum
	Typedef

Function Documentation

hal_irtx_status_t hal_irtx_configure_pulse_data_carrier	(	uint32_t	frequency,
		uint32_t	duty_cycle
	)

This function configures the pulse data carrier.

Parameters

[in]	frequency	pulse data carrier frequency.
[in]	duty_cycle	pulse data carrier duty cycle.

Returns

Indicates whether this function call is successful or not. If the return value is HAL_IRTX_STATUS_OK, the operation completed successfully. If the return value is HAL_IRTX_STATUS_ERROR, the operation failed.

Example

Sample code, please refer to How to use this driver.

hal_irtx_status_t hal_irtx_deinit

(

void

)

This function deinitializes the IRTX hardware clock.

Returns

Indicates whether this function call is successful or not. If the return value is HAL_IRTX_STATUS_OK, the operation completed successfully. If the return value is HAL_IRTX_STATUS_ERROR, the operation failed.

Example

Sample code, please refer to How to use this driver.

See also

hal_irtx_init()

hal_irtx_status_t hal_irtx_get_running_status

(

hal_irtx_running_status_t *

running_status

)

This function gets the current state of the IRTX.

Parameters

[out]

running_status

is the current running status. HAL_IRTX_BUSY means the IRTX is in busy state. HAL_IRTX_IDLE means the IRTX is in idle state, which can be used to transfer data immediately.

Returns

Indicates whether this function call is successful or not. If the return value is HAL_IRTX_STATUS_OK, the operation completed successfully. If the return value is HAL_IRTX_STATUS_ERROR, the operation failed.

Example

Sample code, please refer to How to use this driver.

hal_irtx_status_t hal_irtx_init

(

void

)

This function initializes the IRTX hardware clock.

Returns

Indicates whether this function call is successful or not. If the return value is HAL_IRTX_STATUS_OK, the operation completed successfully. If the return value is HAL_IRTX_STATUS_ERROR, the operation failed.

Example

Sample code please refer to How to use this driver.

See also

hal_irtx_deinit()

hal_irtx_status_t hal_irtx_register_pulse_data_callback	(	hal_irtx_pulse_data_callback_t	callback,
		void *	user_data
	)

This function registers the PWD encoding format data callback.

Call it after the transmission is complete.

Parameters

[in]	callback	user defined callback function.
[in]	user_data	a user defined extension data.

Returns

Indicates whether this function call is successful or not. If the return value is HAL_IRTX_STATUS_OK, the operation completed successfully. If the return value is HAL_IRTX_STATUS_ERROR, the operation failed.

Example

Sample code, please refer to How to use this driver.

hal_irtx_status_t hal_irtx_send_nec_data	(	hal_irtx_repeat_code_t	repeat_code,
		const uint8_t	data[(12)],
		uint32_t	bit_length
	)

This function sends the data in the NEC encoding format.

Parameters

[in]	repeat_code	repeat code for the NEC IRTX.
[in]	data	data to be sent.
[in]	bit_length	the number of bits in the message.

Returns

Indicates whether this function call is successful or not. If the return value is HAL_IRTX_STATUS_OK, the operation completed successfully. If the return value is HAL_IRTX_STATUS_ERROR, the operation failed.

Example

Sample code, please refer to How to use this driver.

hal_irtx_status_t hal_irtx_send_pulse_data	(	uint32_t	base_period,
		uint8_t *	data,
		uint32_t	length
	)

This function sends the data in the PWD encoded format.

Parameters

[in]	base_period	the base period for sending data.
[in]	data	the data content to be sent.
[in]	length	data length in bytes.

Returns

Indicates whether this function call is successful or not. If the return value is HAL_IRTX_STATUS_OK, the operation completed successfully. If the return value is HAL_IRTX_STATUS_ERROR, the operation failed.

Example

Sample code, please refer to How to use this driver.

hal_irtx_status_t hal_irtx_send_rc5_data	(	hal_irtx_repeat_code_t	repeat_code,
		const uint8_t	data[(12)],
		uint32_t	bit_length
	)

This function sends the data in the RC5 encoding format.

Parameters

[in]	repeat_code	repeat code for the RC5 IRTX.
[in]	data	the data content to be sent.
[in]	bit_length	the number of bits in the message.

Returns

Indicates whether this function call is successful or not. If the return value is HAL_IRTX_STATUS_OK, the operation completed successfully. If the return value is HAL_IRTX_STATUS_ERROR, the operation failed.

Example

Sample code, please refer to How to use this driver.

hal_irtx_status_t hal_irtx_send_rc6_data	(	hal_irtx_repeat_code_t	repeat_code,
		const uint8_t	data[(12)],
		uint32_t	bit_length
	)

This function sends the data in the RC6 encoding format.

Parameters

[in]	repeat_code	repeat code for the RC6 IRTX.
[in]	data	the data content to be sent.
[in]	bit_length	the number of bits in the message.

Returns

Indicates whether this function call is successful or not. If the return value is HAL_IRTX_STATUS_OK, the operation completed successfully. If the return value is HAL_IRTX_STATUS_ERROR, the operation failed.

Example

Sample code, please refer to How to use this driver.