PIXELRZ - Serial Pixel Interface#

Introduction#

PIXELRZ relays on external addressable LED to be configured correctly. In this example we will use WS2812B LEDS. Check datasheet of WS2812B for timing. To configure the timing, user must call @sl_hal_pixelrz_get_symbol_configuration().

Example#

{
  #define PIXELRZ_GPIO         PB0
  #define PIXELRZ_PIXEL_COUNT  60  // 60 pixels
  #define PIXELRZ_PIXEL_WIDTH  24  // 24 bits per pixel
  #define PIXELRZ_PIXEL_TRAIL  0   // no trail data

  // WS2812B timing values in microseconds. Check datasheet.
  #define WS2812B_T0_HIGH    0.4f
  #define WS2812B_T0_LOW     0.85f
  #define WS2812B_T1_HIGH    0.8f
  #define WS2812B_T1_LOW     0.45f
  #define WS2812B_TRST_HIGH  0.0f
  #define WS2812B_TRST_LOW   60.0f

  sl_hal_pixelrz_init_t init_serial = SL_HAL_PIXELRZ_CONFIG_SEQUENTIAL_DEFAULT;
  uint32_t freq;

  sl_clock_manager_enable_bus_clock(SL_BUS_CLOCK_PIXELRZ0);
  sl_clock_manager_get_clock_branch_frequency(SL_CLOCK_BRANCH_PIXELRZCLK, &freq);

  init_serial.pixel_number = PIXELRZ_PIXEL_COUNT;
  init_serial.pixel_width = PIXELRZ_PIXEL_WIDTH;
  init_serial.trail_data_width = PIXELRZ_PIXEL_TRAIL;

  init_serial.zero_symbol = sl_hal_pixelrz_get_symbol_configuration(WS2812B_T0_HIGH, WS2812B_T0_LOW, freq);
  init_serial.one_symbol = sl_hal_pixelrz_get_symbol_configuration(WS2812B_T1_HIGH, WS2812B_T1_LOW, freq);
  init_serial.reset_symbol = sl_hal_pixelrz_get_symbol_configuration(WS2812B_TRST_HIGH, WS2812B_TRST_LOW, freq);

  // Configure the GPIO.
  sl_gpio_set_pin_mode(PIXELRZ_GPIO, SL_GPIO_MODE_PUSH_PULL, 0);
  GPIO->PIXELRZROUTE[PIXELRZ_NUM(PIXELRZ0)].RZTXOUTROUTE = (PIXELRZ_GPIO->port << _GPIO_PIXELRZ_RZTXOUTROUTE_PORT_SHIFT)
                                                         | (PIXELRZ_GPIO->pin << _GPIO_PIXELRZ_RZTXOUTROUTE_PIN_SHIFT);
  GPIO->PIXELRZROUTE[PIXELRZ_NUM(PIXELRZ0)].ROUTEEN = GPIO_PIXELRZ_ROUTEEN_RZTXOUTPEN;

  sl_hal_pixelrz_init(PIXELRZ0, &init_serial);
  sl_hal_pixelrz_enable(PIXELRZ0);
  sl_hal_pixelrz_enable_tx(PIXELRZ0);
  sl_hal_pixelrz_wait_sync(PIXELRZ0);

  // User can start transmitting data directly or using LDMA.
}

Modules#

sl_hal_pixelrz_symbol_t

sl_hal_pixelrz_init_t

Enumerations#

enum

sl_hal_pixelrz_mode_t {

SL_HAL_PIXELRZ_MODE_SEQUENTIAL = _PIXELRZ_CFG_MODE_SEQUENTIAL

SL_HAL_PIXELRZ_MODE_PARALLEL = _PIXELRZ_CFG_MODE_PARALLEL

}

PIXELRZ mode. Serial or parallel.

enum

sl_hal_pixelrz_trigger_t {

SL_HAL_PIXELRZ_TRIG_SW = _PIXELRZ_CFG_TRIGSEL_SW

SL_HAL_PIXELRZ_TRIG_AUTO = _PIXELRZ_CFG_TRIGSEL_AUTO

SL_HAL_PIXELRZ_TRIG_PRS = _PIXELRZ_CFG_TRIGSEL_PRS

}

The frame trigger source.

Functions#

void

sl_hal_pixelrz_init(PIXELRZ_TypeDef *pixelrz, const sl_hal_pixelrz_init_t *init)

Initialize PIXELRZ.

sl_hal_pixelrz_symbol_t

sl_hal_pixelrz_get_symbol_configuration(float time_high_us, float time_low_us, uint32_t freq)

Get symbol from time settings.

void

sl_hal_pixelrz_wait_sync(PIXELRZ_TypeDef *pixelrz)

Wait for ongoing sync of register(s) to the low-frequency domain to complete.

void

sl_hal_pixelrz_wait_ready(PIXELRZ_TypeDef *pixelrz)

Wait for disabling to finish.

void

sl_hal_pixelrz_enable(PIXELRZ_TypeDef *pixelrz)

Enable PIXELRZ.

void

sl_hal_pixelrz_disable(PIXELRZ_TypeDef *pixelrz)

Disable PIXELRZ.

void

sl_hal_pixelrz_tx(PIXELRZ_TypeDef *pixelrz, uint32_t data)

Transmits one data word.

void

sl_hal_pixelrz_enable_tx(PIXELRZ_TypeDef *pixelrz)

Enable PIXELRZ transmitter.

void

sl_hal_pixelrz_disable_tx(PIXELRZ_TypeDef *pixelrz)

Disable PIXELRZ transmitter.

void

sl_hal_pixelrz_clear_tx(PIXELRZ_TypeDef *pixelrz)

Clear TX FIFO.

void

sl_hal_pixelrz_reset(PIXELRZ_TypeDef *pixelrz)

Reset the PIXELRZ.

uint32_t

sl_hal_pixelrz_get_status(PIXELRZ_TypeDef *pixelrz)

Gets PIXELRZ STATUS register value.

void

sl_hal_pixelrz_clear_interrupts(PIXELRZ_TypeDef *pixelrz, uint32_t flags)

Clear one or more pending PIXELRZ interrupts.

void

sl_hal_pixelrz_set_interrupts(PIXELRZ_TypeDef *pixelrz, uint32_t flags)

Set one or more pending PIXELRZ interrupts from Software.

void

sl_hal_pixelrz_disable_interrupts(PIXELRZ_TypeDef *pixelrz, uint32_t flags)

Disable one or more PIXELRZ interrupts.

void

sl_hal_pixelrz_enable_interrupts(PIXELRZ_TypeDef *pixelrz, uint32_t flags)

Enable one or more PIXELRZ interrupts.

uint32_t

sl_hal_pixelrz_get_pending_interrupts(PIXELRZ_TypeDef *pixelrz)

Get pending PIXELRZ interrupt flags.

uint32_t

sl_hal_pixelrz_get_enabled_interrupts(PIXELRZ_TypeDef *pixelrz)

Get enabled PIXELRZ interrupt flags.

uint32_t

sl_hal_pixelrz_get_enabled_pending_interrupts(PIXELRZ_TypeDef *pixelrz)

Get enabled and pending PIXELRZ interrupt flags.

Macros#

#define

SL_HAL_PIXELRZ_REF_VALID (pixelrz_ref)

Check if PIXELRZ instance is valid.

#define

SL_HAL_PIXELRZ_SEQUENTIAL_INIT_DEFAULT undefined

Default sequential configuration.

#define

SL_HAL_PIXELRZ_PARALLEL_INIT_DEFAULT undefined

Default parallel configuration.

Enumeration Documentation#

sl_hal_pixelrz_mode_t#

sl_hal_pixelrz_mode_t

PIXELRZ mode. Serial or parallel.

Enumerator
SL_HAL_PIXELRZ_MODE_SEQUENTIAL	Sequential mode.
SL_HAL_PIXELRZ_MODE_PARALLEL	Parallel mode.

sl_hal_pixelrz_trigger_t#

sl_hal_pixelrz_trigger_t

The frame trigger source.

Enumerator
SL_HAL_PIXELRZ_TRIG_SW	Software trigger mode.
SL_HAL_PIXELRZ_TRIG_AUTO	Auto trigger mode.
SL_HAL_PIXELRZ_TRIG_PRS	Software trigger mode.

Function Documentation#

sl_hal_pixelrz_init#

void sl_hal_pixelrz_init (PIXELRZ_TypeDef * pixelrz, const sl_hal_pixelrz_init_t * init)

Initialize PIXELRZ.

Parameters

Type	Direction	Argument Name	Description
PIXELRZ_TypeDef *	[in]	pixelrz	A pointer to the PIXELRZ peripheral register block.
const sl_hal_pixelrz_init_t *	[in]	init	A pointer to the PIXELRZ initialization structure.

sl_hal_pixelrz_get_symbol_configuration#

sl_hal_pixelrz_symbol_t sl_hal_pixelrz_get_symbol_configuration (float time_high_us, float time_low_us, uint32_t freq)

Get symbol from time settings.

Parameters

Type	Direction	Argument Name	Description
float	[in]	time_high_us	High time in microseconds.
float	[in]	time_low_us	Low time in microseconds.
uint32_t	[in]	freq	PIXELRZ source clock frequency.

Check the datasheet for timing configuration.

Returns

Symbol high/low time values in clock cycles.

sl_hal_pixelrz_wait_sync#

void sl_hal_pixelrz_wait_sync (PIXELRZ_TypeDef * pixelrz)

Wait for ongoing sync of register(s) to the low-frequency domain to complete.

Parameters

Type	Direction	Argument Name	Description
PIXELRZ_TypeDef *	[in]	pixelrz	Pointer to the PIXELRZ peripheral register block.

sl_hal_pixelrz_wait_ready#

void sl_hal_pixelrz_wait_ready (PIXELRZ_TypeDef * pixelrz)

Wait for disabling to finish.

Parameters

Type	Direction	Argument Name	Description
PIXELRZ_TypeDef *	[in]	pixelrz	Pointer to the PIXELRZ peripheral register block.

sl_hal_pixelrz_enable#

void sl_hal_pixelrz_enable (PIXELRZ_TypeDef * pixelrz)

Enable PIXELRZ.

Parameters

Type	Direction	Argument Name	Description
PIXELRZ_TypeDef *	[in]	pixelrz	Pointer to the PIXELRZ peripheral register block.

sl_hal_pixelrz_disable#

void sl_hal_pixelrz_disable (PIXELRZ_TypeDef * pixelrz)

Disable PIXELRZ.

Parameters

Type	Direction	Argument Name	Description
PIXELRZ_TypeDef *	[in]	pixelrz	Pointer to the PIXELRZ peripheral register block.

sl_hal_pixelrz_tx#

void sl_hal_pixelrz_tx (PIXELRZ_TypeDef * pixelrz, uint32_t data)

Transmits one data word.

Parameters

Type	Direction	Argument Name	Description
PIXELRZ_TypeDef *	[in]	pixelrz	Pointer to the PIXELRZ peripheral register block.
uint32_t	[in]	data	Data to transmit.

Data will be written into FIFO.

sl_hal_pixelrz_enable_tx#

void sl_hal_pixelrz_enable_tx (PIXELRZ_TypeDef * pixelrz)

Enable PIXELRZ transmitter.

Parameters

Type	Direction	Argument Name	Description
PIXELRZ_TypeDef *	[in]	pixelrz	Pointer to the PIXELRZ peripheral register block.

The behaviour of this command will depend on the trigger configuration. If trigger is set to Software mode, this command will trigger transmission of one frame and stop, user must run this command for every frame. If trigger is set to Auto mode, the data will be transmitted whenever there's data in the FIFO and it will trigger transmission of all frames.

sl_hal_pixelrz_disable_tx#

void sl_hal_pixelrz_disable_tx (PIXELRZ_TypeDef * pixelrz)

Disable PIXELRZ transmitter.

Parameters

Type	Direction	Argument Name	Description
PIXELRZ_TypeDef *	[in]	pixelrz	Pointer to the PIXELRZ peripheral register block.

sl_hal_pixelrz_clear_tx#

void sl_hal_pixelrz_clear_tx (PIXELRZ_TypeDef * pixelrz)

Clear TX FIFO.

Parameters

Type	Direction	Argument Name	Description
PIXELRZ_TypeDef *	[in]	pixelrz	Pointer to the PIXELRZ peripheral register block.

sl_hal_pixelrz_reset#

void sl_hal_pixelrz_reset (PIXELRZ_TypeDef * pixelrz)

Reset the PIXELRZ.

Parameters

Type	Direction	Argument Name	Description
PIXELRZ_TypeDef *	[in]	pixelrz	A pixelrz peripheral module.

sl_hal_pixelrz_get_status#

uint32_t sl_hal_pixelrz_get_status (PIXELRZ_TypeDef * pixelrz)

Gets PIXELRZ STATUS register value.

Parameters

Type	Direction	Argument Name	Description
PIXELRZ_TypeDef *	[in]	pixelrz	A PIXELRZ peripheral module.

Returns

Current STATUS register value.

sl_hal_pixelrz_clear_interrupts#

void sl_hal_pixelrz_clear_interrupts (PIXELRZ_TypeDef * pixelrz, uint32_t flags)

Clear one or more pending PIXELRZ interrupts.

Parameters

Type	Direction	Argument Name	Description
PIXELRZ_TypeDef *	[in]	pixelrz	Pointer to the PIXELRZ peripheral register block.
uint32_t	[in]	flags	Pending PIXELRZ interrupt source(s) to clear. Use one or more valid interrupt flags for the PIXELRZ module (PIXELRZ_IF_nnn) OR'ed together.

sl_hal_pixelrz_set_interrupts#

void sl_hal_pixelrz_set_interrupts (PIXELRZ_TypeDef * pixelrz, uint32_t flags)

Set one or more pending PIXELRZ interrupts from Software.

Parameters

Type	Direction	Argument Name	Description
PIXELRZ_TypeDef *	[in]	pixelrz	Pointer to the PIXELRZ peripheral register block.
uint32_t	[in]	flags	PIXELRZ interrupt source(s) to set to pending. Use one or more valid interrupt flags for the PIXELRZ module (PIXELRZ_IF_nnn) OR'ed together.

sl_hal_pixelrz_disable_interrupts#

void sl_hal_pixelrz_disable_interrupts (PIXELRZ_TypeDef * pixelrz, uint32_t flags)

Disable one or more PIXELRZ interrupts.

Parameters

Type	Direction	Argument Name	Description
PIXELRZ_TypeDef *	[in]	pixelrz	Pointer to the PIXELRZ peripheral register block.
uint32_t	[in]	flags	PIXELRZ interrupt source(s) to disable. Use one or more valid interrupt flags for the PIXELRZ module (PIXELRZ_IEN_nnn) OR'ed together.

sl_hal_pixelrz_enable_interrupts#

void sl_hal_pixelrz_enable_interrupts (PIXELRZ_TypeDef * pixelrz, uint32_t flags)

Enable one or more PIXELRZ interrupts.

Parameters

Type	Direction	Argument Name	Description
PIXELRZ_TypeDef *	[in]	pixelrz	Pointer to the PIXELRZ peripheral register block.
uint32_t	[in]	flags	PIXELRZ interrupt source(s) to enable. Use one or more valid interrupt flags for the PIXELRZ module (PIXELRZ_IEN_nnn) OR'ed together.

Note

Depending on the use, a pending interrupt may already be set prior to enabling the interrupt. To ignore a pending interrupt, consider using sl_hal_pixelrz_clear_interrupts() prior to enabling the interrupt.

sl_hal_pixelrz_get_pending_interrupts#

uint32_t sl_hal_pixelrz_get_pending_interrupts (PIXELRZ_TypeDef * pixelrz)

Get pending PIXELRZ interrupt flags.

Parameters

Type	Direction	Argument Name	Description
PIXELRZ_TypeDef *	[in]	pixelrz	Pointer to the PIXELRZ peripheral register block.

Note

Event bits are not cleared by this function.

Returns

PIXELRZ interrupt source(s) pending. Returns one or more valid interrupt flags for the PIXELRZ module (PIXELRZ_IF_nnn) OR'ed together.

sl_hal_pixelrz_get_enabled_interrupts#

uint32_t sl_hal_pixelrz_get_enabled_interrupts (PIXELRZ_TypeDef * pixelrz)

Get enabled PIXELRZ interrupt flags.

Parameters

Type	Direction	Argument Name	Description
PIXELRZ_TypeDef *	[in]	pixelrz	Pointer to the PIXELRZ peripheral register block.

Note

Event bits are not cleared by this function.

Returns

PIXELRZ interrupt source(s) enabled. Returns one or more valid enabled interrupt sources in PIXELRZx_IEN_nnn.

sl_hal_pixelrz_get_enabled_pending_interrupts#

uint32_t sl_hal_pixelrz_get_enabled_pending_interrupts (PIXELRZ_TypeDef * pixelrz)

Get enabled and pending PIXELRZ interrupt flags.

Parameters

Type	Direction	Argument Name	Description
PIXELRZ_TypeDef *	[in]	pixelrz	Pointer to the PIXELRZ peripheral register block.

Useful for handling more interrupt sources in the same interrupt handler.

Note

Interrupt flags are not cleared by this function.

Returns

Pending and enabled PIXELRZ interrupt sources. The return value is the bitwise AND combination of
- the OR combination of enabled interrupt sources in PIXELRZx_IEN_nnn register (PIXELRZx_IEN_nnn) and
- the OR combination of valid interrupt flags of the PIXELRZ module (PIXELRZx_IF_nnn).