Synchronous Serial Interface#

ssi_event_typedef_t#

ssi_event_typedef_t

Enumeration for different SSI callback events.

ssi_peripheral_clock_mode_t#

ssi_peripheral_clock_mode_t

Enumeration for different SSI peripheral clock modes.

sl_ssi_instance_t#

sl_ssi_instance_t

Enumeration for different SSI peripheral device modes.

sl_ssi_slave_number_t#

sl_ssi_slave_number_t

Enumeration for SSI Secondary numbers.

sl_ssi_power_state_t#

typedef ARM_POWER_STATE sl_ssi_power_state_t

renaming arm power state structure

sl_ssi_status_t#

typedef ARM_SPI_STATUS sl_ssi_status_t

renaming arm SPI status

sl_ssi_driver_t#

typedef ARM_DRIVER_SPI sl_ssi_driver_t

Renaming SSI driver structure.

sl_ssi_handle_t#

typedef const void* sl_ssi_handle_t

SSI Handle to be passed into APIs.

sl_ssi_signal_event_t#

typedef ARM_SPI_SignalEvent_t sl_ssi_signal_event_t

Callback typedef for SSI.

release#

uint8_t sl_ssi_version_t::release

Release version number.

major#

uint8_t sl_ssi_version_t::major

SQA version number.

minor#

uint8_t sl_ssi_version_t::minor

DEV version number.

bit_width#

uint8_t sl_ssi_control_config_t::bit_width

bit width either 8 or 16 bit

device_mode#

uint32_t sl_ssi_control_config_t::device_mode

mode such as Master or Slave mode

clock_mode#

uint32_t sl_ssi_control_config_t::clock_mode

clock mode such as CPOL0 CPHA1

baud_rate#

uint32_t sl_ssi_control_config_t::baud_rate

baud rate for SSI

receive_sample_delay#

uint32_t sl_ssi_control_config_t::receive_sample_delay

Delay for receive input signal.

division_factor#

uint16_t sl_ssi_clock_config_t::division_factor

Clock Division Factor.

intf_pll_500_control_value#

uint16_t sl_ssi_clock_config_t::intf_pll_500_control_value

intf PLL control value

intf_pll_clock#

uint32_t sl_ssi_clock_config_t::intf_pll_clock

intf PLL clock frequency

intf_pll_reference_clock#

uint32_t sl_ssi_clock_config_t::intf_pll_reference_clock

intf PLL reference clock frequency

soc_pll_clock#

uint32_t sl_ssi_clock_config_t::soc_pll_clock

SoC PLL Clock frequency.

soc_pll_reference_clock#

uint32_t sl_ssi_clock_config_t::soc_pll_reference_clock

SoC PLL reference clock frequency.

soc_pll_mm_count_value#

uint8_t sl_ssi_clock_config_t::soc_pll_mm_count_value

SoC PLL count value.

sl_si91x_ssi_configure_clock#

sl_status_t sl_si91x_ssi_configure_clock (sl_ssi_clock_config_t * clock_config)

This API will configures the SSI clock.

To set the clock for the SSI peripheral, Configures the PLL clock and SOC clock with the value set by user in the clock configuration structure.

Returns

• status 0 if successful, else error code as follow.

  • SL_STATUS_OK (0x0000) - Success, timer clock-source parameters configured properly

  • SL_STATUS_NULL_POINTER (0x0022) - The parameter is null pointer

  • SL_STATUS_INVALID_PARAMETER (0x0021) - Parameters are invalid

  • SL_STATUS_FAIL (0x0001) - The function is failed

  • SL_STATUS_NOT_INITIALIZED (0x0011) - Clock is not initialized

sl_si91x_ssi_init#

sl_status_t sl_si91x_ssi_init (sl_ssi_instance_t instance, sl_ssi_handle_t * ssi_handle)

This API will initialize the SSI.

This will initialize the SSI and if the DMA is enabled, it also initializes the DMA module. Pass the address of the pointer for storing the SSI Primary/Secondary/ULP Primary handle, which can be used in future for other function calls.

Returns

• status 0 if successful, else error code as follow.

  • SL_STATUS_OK (0x0000) - Success, otherwise fail error code as follow

  • SL_STATUS_INVALID_PARAMETER (0x0021) - Parameters are invalid

  • SL_STATUS_BUSY (0x0004) - Driver is busy

sl_si91x_ssi_deinit#

sl_status_t sl_si91x_ssi_deinit (sl_ssi_handle_t ssi_handle)

This API will uninitialize the SSI.

This will uninitialize the SSI and also if the DMA is enabled, it also uninitializes the DMA module.

Returns

• status 0 if successful, else error code as follow.

  • SL_STATUS_OK (0x0000) - Success, otherwise fail error code as follow

  • SL_STATUS_NULL_POINTER (0x0022) - The parameter is null pointer

Note

• When the SSI module is used in combination with other peripherals, while de-initializing in the application, refer to the notes below:

  1. Whenever sl_si91x_ssi_deinit() gets called it will power down the domain(PERI_EFUSE) which contains different peripherals mentioned below. USART, UART, I2C, SSI Master, SSI Slave, Generic-SPI Master, I2S Master, I2S Slave, Micro-DMA Controller, Config Timer, Random-Number Generator, CRC Accelerator, SIO, QEI, MCPWM and EFUSE. Since deinit power downs the PERI_EFUSE doamin, it's recommended to call the sl_si91x_ssi_deinit() API at the end of the application.

  2. Few peripherals (ULP Peripherals, UULP Peripherals, GPDMA and SDIO-SPI) have seperate domains that can be powered down indepedently. For additional details, refer to the Power architecture section in the Hardware Reference Manual e.g., To power down ULP SSI, use the API below: RSI_PS_M4ssPeriPowerDown(ULPSS_PWRGATE_ULP_SSI); Here, ULP_SSI has seperate power domain ULPSS_PWRGATE_ULP_SSI, which can be powered down indepedently. Refer to the rsi_power_save.h file for all power gates definitions.

sl_si91x_ssi_set_configuration#

sl_status_t sl_si91x_ssi_set_configuration (sl_ssi_handle_t ssi_handle, sl_ssi_control_config_t * control_configuration, sl_ssi_slave_number_t slave_number)

This API will control and configure the SSI.

This will control and configure the SSI. As part of that, following parameters are configured:

• Mode (Primary/Secondary/ULP Primary)

• bit_width (4 bit to 16 bit)

• clock_mode/Frame format (mode0 to mode3, TI and Microwire)

• bitrate (10 Mbps to 40 Mbps)

• Rx sample delay (0 to 63).

Returns

• status 0 if successful, else error code as follow.

  • SL_STATUS_OK (0x0000) - Success

  • SL_STATUS_NULL_POINTER (0x0022) - The parameter is null pointer

  • SL_STATUS_INVALID_PARAMETER (0x0021) - Parameters are invalid

  • SL_STATUS_FAIL (0x0001) - The function is failed

  • SL_STATUS_NOT_SUPPORTED (0x000F) - Parameter is not supported

  • SL_STATUS_BUSY (0x0004) - Driver is busy

  • SL_STATUS_INVALID_MODE (0x0024) - Slave select Mode is invalid

  • SL_STATUS_INVALID_TYPE (0x0026) - SPI frame format is not valid

  • SL_STATUS_INVALID_RANGE (0x0028) - Data bits (frame length) is not in range

sl_si91x_ssi_receive_data#

sl_status_t sl_si91x_ssi_receive_data (sl_ssi_handle_t ssi_handle, void * data, uint32_t data_length)

This API will receive data from the secondary device.

This will receive data from the secondary device. If DMA is enabled, it configures the DMA channel and required parameters. When the received data is equal to data_length passed in this function, a callback event is generated which can be registered using sl_si91x_ssi_register_event_callback.

• Pre-conditions:

  • sl_si91x_ssi_configure_clock

  • sl_si91x_ssi_init

  • sl_si91x_ssi_set_configuration

  • sl_si91x_ssi_set_slave_number

Returns

• status 0 if successful, else error code as follow.

  • SL_STATUS_OK (0x0000) - Success

  • SL_STATUS_NULL_POINTER (0x0022) - The parameter is null pointer

  • SL_STATUS_INVALID_PARAMETER (0x0021) - Parameters are invalid

  • SL_STATUS_FAIL (0x0001) - The function is failed

  • SL_STATUS_BUSY (0x0004) - Driver is busy

sl_si91x_ssi_send_data#

sl_status_t sl_si91x_ssi_send_data (sl_ssi_handle_t ssi_handle, const void * data, uint32_t data_length)

This API will send data to the secondary device.

If DMA is enabled, it configures the DMA channel and required parameters. When the send data is equal to data_length passed in this function, a callback event is generated which can be registered using sl_si91x_ssi_register_event_callback.

• Pre-conditions:

  • sl_si91x_ssi_configure_clock

  • sl_si91x_ssi_init

  • sl_si91x_ssi_set_configuration

  • sl_si91x_ssi_set_slave_number

Returns

• status 0 if successful, else error code as follow.

  • SL_STATUS_OK (0x0000) - Success

  • SL_STATUS_NULL_POINTER (0x0022) - The parameter is null pointer

  • SL_STATUS_INVALID_PARAMETER (0x0021) - Parameters are invalid

  • SL_STATUS_FAIL (0x0001) - The function is failed

  • SL_STATUS_BUSY (0x0004) - Driver is busy

sl_si91x_ssi_transfer_data#

sl_status_t sl_si91x_ssi_transfer_data (sl_ssi_handle_t ssi_handle, const void * data_out, void * data_in, uint32_t data_length)

Send and receive data to the secondary device simultaneously.

If DMA is enabled, it configures the DMA channel and required parameters. When the received data and send data is equal to data_length passed in this function, a callback event is generated which can be registered using sl_si91x_ssi_register_event_callback.

• Pre-conditions:

  • sl_si91x_ssi_configure_clock

  • sl_si91x_ssi_init

  • sl_si91x_ssi_set_configuration

  • sl_si91x_ssi_set_slave_number

Returns

• status 0 if successful, else error code

  • SL_STATUS_OK (0x0000) - Success

  • SL_STATUS_NULL_POINTER (0x0022) - The parameter is null pointer

  • SL_STATUS_INVALID_PARAMETER (0x0021) - Parameters are invalid

  • SL_STATUS_FAIL (0x0001) - The function is failed

  • SL_STATUS_BUSY (0x0004) - Driver is busy

sl_si91x_ssi_get_version#

sl_ssi_version_t sl_si91x_ssi_get_version (void )

This API will get the SSI version.

This will get the SSI version. It returns the API version of SSI.

Returns

• driver version.

sl_si91x_ssi_get_status#

sl_ssi_status_t sl_si91x_ssi_get_status (sl_ssi_handle_t ssi_handle)

This API will get the transfer status SSI.

This will get the transfer status SSI. It returns the sl_ssi_status_t type structure. -The members are:

• Busy

• Data Lost

• Mode Fault It is generally used to poll the busy status of SSI Master/ULP Master.

  • Pre-conditions:

sl_si91x_ssi_configure_clock

• sl_si91x_ssi_init

• sl_si91x_ssi_set_configurationReturns

  • ( sl_ssi_status_t) type structure

sl_si91x_ssi_get_rx_data_count#

uint32_t sl_si91x_ssi_get_rx_data_count (sl_ssi_handle_t ssi_handle)

This API will get data receive count of the SSI.

This will get data receive count of the SSI and it returns the number of data received at the time of function call.

• Pre-conditions:

  • sl_si91x_ssi_configure_clock

  • sl_si91x_ssi_init

  • sl_si91x_ssi_set_configuration

Returns

• uint32_t value of the RX data count

sl_si91x_ssi_get_tx_data_count#

uint32_t sl_si91x_ssi_get_tx_data_count (sl_ssi_handle_t ssi_handle)

This API will get the transmit data count of SSI.

This will get the transmit data count of SSI. It returns the number of data transmit at the time of function call.

• Pre-conditions:

  • sl_si91x_ssi_configure_clock

  • sl_si91x_ssi_init

  • sl_si91x_ssi_set_configuration

Returns

• uint32_t value of the tx data count

sl_si91x_ssi_register_event_callback#

sl_status_t sl_si91x_ssi_register_event_callback (sl_ssi_handle_t ssi_handle, sl_ssi_signal_event_t callback_event)

This API will register the user event callback.

It registers the callback, i.e., stores the callback function address and pass to the variable that is called in Interrupt Handler. If another callback is registered without unregistering previous callback then, it returns an error code as follow, so it is mandatory to unregister the callback before registering another callback.

Returns

• status 0 if successful, else error code as follow.

  • SL_STATUS_BUSY (0x0004) - The callback is already registered, unregister previous callback before registering new one.

  • SL_STATUS_OK (0x0000) - Success

  • SL_STATUS_NULL_POINTER (0x0022) - The parameter is null pointer

sl_si91x_ssi_unregister_event_callback#

void sl_si91x_ssi_unregister_event_callback (void )

This API will unregister the user event callback.

It unregisters the callback, i.e., clears the callback function address and passes a NULL value to the variable.

• Pre-conditions:

  • sl_si91x_ssi_register_event_callback

sl_si91x_ssi_get_clock_division_factor#

uint32_t sl_si91x_ssi_get_clock_division_factor (sl_ssi_handle_t ssi_handle)

This API will fetch the clock division factor.

The clock division factor is calculated based on the peripheral clock configured. It decides the baud rate of SSI.

Returns

• factor(int32_t) The value of clock division fac

sl_si91x_ssi_get_frame_length#

uint32_t sl_si91x_ssi_get_frame_length (sl_ssi_handle_t ssi_handle)

This API will fetch the frame length i.e., bit width and also.

The frame length ranges between 4 and 16.

Returns

• frame_length (uint32_t) The value of frame length

sl_si91x_ssi_get_tx_fifo_threshold#

uint32_t sl_si91x_ssi_get_tx_fifo_threshold (sl_ssi_handle_t ssi_handle)

This API will fetch the transmit FIFO threshold value, this value controls the level of entries at which the transmit FIFO controller triggers an interrupt.

Returns

• Transmit fifo threshold (uint32_t) The value of transmit fifo threshold

sl_si91x_ssi_get_rx_fifo_threshold#

uint32_t sl_si91x_ssi_get_rx_fifo_threshold (sl_ssi_handle_t ssi_handle)

This API is to fetch the receiver FIFO threshold value, this value controls the level of entries at which the receive FIFO controller triggers an interrupt.

Returns

• Receiver fifo threshold (uint32_t) The value of receiver fifo threshold

sl_si91x_ssi_get_receiver_sample_delay#

uint32_t sl_si91x_ssi_get_receiver_sample_delay (sl_ssi_handle_t ssi_handle)

This API is to fetch the receiver sample delay value, it used to delay the sample of the RX input signal.

Each value represents a single ssi_clk delay on the sample of the rxd signal.

Returns

• Receiver sample delay (uint32_t) The value of receiver sample delay

sl_si91x_ssi_set_slave_number#

__STATIC_INLINE sl_status_t sl_si91x_ssi_set_slave_number (uint8_t number)

This API will set the secondary number in multi-secondary operation.

For single secondary also, this API needs to be called before transferring the data.

Returns

• none