Low Level Functions

group group_smif_low_level_functions

The SMIF interface can be used to transmit different types of commands.

Each command has different phases: command, dummy cycles, and transmit and receive data which require separate APIs.

During the time that Slave Select line is active (LOW) the clock signal (CLK) is toggled while command information is first transferred on the data (IO) signals from the master to the slave. The clock continues to toggle during any period required for information access in the slave. The clock continues to toggle during the transfer of read data from the slave to the master or write data from the master to the slave. When the master has transferred the desired amount of data, the master drives the Slave Select line inactive (HIGH). Basic flow for read/write commands using Cy_SMIF_TransmitCommand, Cy_SMIF_TransmitData, Cy_SMIF_ReceiveData and Cy_SMIF_SendDummyCycles with a Quad SPI interface.

../../../_images/smif_1_0_p03_rw_cmd.png

The sequence of the PDL functions required in a read or write transaction is: Cy_SMIF_TransmitCommand() -> Cy_SMIF_SendDummyCycles() -> Cy_SMIF_ReceiveData() / Cy_SMIF_TransmitData() -> Cy_SMIF_BusyCheck(). The address is sent as part of the Cy_SMIF_TransmitCommand() function. No separate function call is required.

Functions

cy_en_smif_status_t Cy_SMIF_Init(SMIF_Type *base, cy_stc_smif_config_t const *config, uint32_t timeout, cy_stc_smif_context_t *context)

This function initializes the SMIF block as a communication block.

The user must ensure that the SMIF interrupt is disabled while this function is called. Enabling the interrupts can lead to triggering in the middle of the initialization operation, which can lead to erroneous initialization.

As parameters, this function takes the SMIF register base address and a context structure along with the configuration needed for the SMIF block, stored in a config

note

Make sure that the interrupts are initialized and disabled.

Return

Parameters
  • base: Holds the base address of the SMIF block registers.

  • config: Passes a configuration structure that configures the SMIF block for operation.

  • timeout: A timeout in microseconds for blocking APIs in use.

  • context: Passes a configuration structure that contains the transfer parameters of the SMIF block.

void Cy_SMIF_DeInit(SMIF_Type *base)

This function de-initializes the SMIF block to default values.

note

The SMIF must be disabled before calling the function. Call Cy_SMIF_Disable

Parameters
  • base: Holds the base address of the SMIF block registers.

void Cy_SMIF_SetDataSelect(SMIF_Type *base, cy_en_smif_slave_select_t slaveSelect, cy_en_smif_data_select_t dataSelect)

This function configures the data select option for a specific slave.

The selection provides pre-set combinations for connecting the SMIF data lines to the GPIOs.

Parameters
  • base: Holds the base address of the SMIF block registers.

  • slaveSelect: The slave device ID. This number is either CY_SMIF_SLAVE_SELECT_0 or CY_SMIF_SLAVE_SELECT_1 or CY_SMIF_SLAVE_SELECT_2 or CY_SMIF_SLAVE_SELECT_3 (cy_en_smif_slave_select_t). It defines the slave select line to be used during the transmission.

  • dataSelect: This parameter selects the data select option. cy_en_smif_data_select_t

void Cy_SMIF_SetMode(SMIF_Type *base, cy_en_smif_mode_t mode)

Sets the mode of operation for the SMIF.

The mode of operation can be the XIP mode where the slave devices are mapped as memories and are directly accessed from the PSoC register map. In the MMIO mode, the SMIF block acts as a simple SPI engine.

note

Interrupt and triggers and not working in XIP mode, see TRM for details

Parameters
  • base: Holds the base address of the SMIF block registers.

  • mode: The mode of the SMIF operation.

cy_en_smif_mode_t Cy_SMIF_GetMode(SMIF_Type const *base)

Reads the mode of operation for the SMIF.

The mode of operation can be the XIP mode where the slave devices are mapped as memories and are directly accessed from the PSoC register map. In the MMIO mode, the SMIF block acts as a simple SPI engine.

Return

The mode of SMIF operation (see cy_en_smif_mode_t).

Parameters
  • base: Holds the base address of the SMIF block registers.

cy_en_smif_status_t Cy_SMIF_TransmitCommand(SMIF_Type *base, uint8_t cmd, cy_en_smif_txfr_width_t cmdTxfrWidth, uint8_t const cmdParam[], uint32_t paramSize, cy_en_smif_txfr_width_t paramTxfrWidth, cy_en_smif_slave_select_t slaveSelect, uint32_t completeTxfr, cy_stc_smif_context_t const *context)

This function transmits a command byte followed by a parameter which is typically an address field.

The transfer is implemented using the TX FIFO. This function also asserts the slave select line. A command to a memory device generally starts with a command byte transmission. This function sets up the slave lines for the rest of the command structure. The Cy_SMIF_TransmitCommand is called before Cy_SMIF_TransmitData or Cy_SMIF_ReceiveData is called. When enabled, the completeTxfr parameter in the function will de-assert the slave select line at the end of the function execution.

note

This function blocks until all the command and associated parameters have been transmitted over the SMIF block or timeout expire.

note

Check Rules for PSoC6 QSPI/SMIF Block Usage for any usage restriction

Return

A status of the command transmit.

Parameters
  • base: Holds the base address of the SMIF block registers.

  • cmd: The command byte to be transmitted.

  • cmdTxfrWidth: The width of command byte transfer cy_en_smif_txfr_width_t.

  • cmdParam: This is the pointer to an array that has bytes to be transmitted after the command byte. Typically, this field has the address bytes associated with the memory command.

  • paramSize: The size of the cmdParam array.

  • paramTxfrWidth: The width of parameter transfer cy_en_smif_txfr_width_t.

  • slaveSelect: Denotes the number of the slave device to which the transfer is made. (0, 1, 2 or 4 - the bit defines which slave to enable) Two-bit enable is possible only for the double quad SPI mode.

  • completeTxfr: Specifies if the slave select line must be de-asserted after transferring the last byte in the parameter array. Typically, this field is set to 0 when this function succeed through Cy_SMIF_TransmitData or Cy_SMIF_ReceiveData.

  • context: Passes a configuration structure that contains the transfer parameters of the SMIF block.

cy_en_smif_status_t Cy_SMIF_TransmitData(SMIF_Type *base, uint8_t const *txBuffer, uint32_t size, cy_en_smif_txfr_width_t transferWidth, cy_smif_event_cb_t TxCompleteCb, cy_stc_smif_context_t *context)

This function is used to transmit data using the SMIF interface.

This function uses the TX Data FIFO to implement the transmit functionality. The function sets up an interrupt to trigger the TX Data FIFO and uses that interrupt to fill the TX Data FIFO until all the data is transmitted. At the end of the transmission, the TxCompleteCb is executed.

note

This function is to be preceded by Cy_SMIF_TransmitCommand where the slave select is selected. The slave is de-asserted at the end of a transmit. The function triggers the transfer and the transfer itself utilizes the interrupt for FIFO operations in the background. Thus, frequent interrupts will be executed after this function is triggered. Since this API is non-blocking and sets up the interrupt to act on the data FIFO, ensure there will be no another instance of the function called before the current instance has completed execution.

note

If the user provides a NULL pointer in this function and does not handle the FIFO transaction, this could either stall or timeout the operation. The transfer statuses returned by Cy_SMIF_GetTransferStatus are no longer valid.

Return

A status of a transmission.

Parameters
  • base: Holds the base address of the SMIF block registers.

  • txBuffer: The pointer to the data to be transferred. If this pointer is a NULL, then the function does not enable the interrupt. This use case is typically used when the FIFO is handled outside the interrupt and is managed in either a polling-based code or a DMA. The user would handle the FIFO management in a DMA or a polling-based code.

Parameters
  • size: The size of txBuffer. Must be > 0 and not greater than 65536.

  • transferWidth: The width of transfer cy_en_smif_txfr_width_t.

  • TxCompleteCb: The callback executed at the end of a transmission. NULL interpreted as no callback.

  • context: Passes a configuration structure that contains the transfer parameters of the SMIF block.

cy_en_smif_status_t Cy_SMIF_TransmitDataBlocking(SMIF_Type *base, uint8_t const *txBuffer, uint32_t size, cy_en_smif_txfr_width_t transferWidth, cy_stc_smif_context_t const *context)

This function implements the transmit data phase in the memory command.

The data is transmitted using the Tx Data FIFO and the TX_COUNT command. This function blocks until completion. The function does not use the interrupts and will use CPU to monitor the FIFO status and move data accordingly. The function returns only on completion.

note

Since this API is blocking, ensure that other transfers finished and it will not be called during non-blocking transfer.

note

If the user provides a NULL pointer in this function and does not handle the FIFO transaction, this could either stall or timeout the operation. The transfer statuses returned by Cy_SMIF_GetTransferStatus are no longer valid.

Return

A status of a transmission.

Parameters
  • base: Holds the base address of the SMIF block registers.

  • txBuffer: The pointer to the data to be transferred. If this pointer is a NULL, then the function does not fill TX_FIFO. The user would handle the FIFO management in a DMA or a polling-based code.

Parameters
  • size: The size of txBuffer. Must be > 0 and not greater than 65536.

  • transferWidth: The width of transfer cy_en_smif_txfr_width_t.

  • context: Passes a configuration structure that contains the transfer parameters of the SMIF block.

cy_en_smif_status_t Cy_SMIF_ReceiveData(SMIF_Type *base, uint8_t *rxBuffer, uint32_t size, cy_en_smif_txfr_width_t transferWidth, cy_smif_event_cb_t RxCompleteCb, cy_stc_smif_context_t *context)

This function implements the receive data phase in the memory command.

The data is received into the RX Data FIFO using the RX_COUNT command. This function sets up the interrupt to trigger on the RX Data FIFO level, and the data is fetched from the RX Data FIFO to the rxBuffer as it gets filled. This function does not block until completion. The completion will trigger the call back function.

note

This function is to be preceded by Cy_SMIF_TransmitCommand. The slave select is de-asserted at the end of the receive. The function triggers the transfer and the transfer itself utilizes the interrupt for FIFO operations in the background. Thus, frequent interrupts will be executed after this function is triggered. This API is non-blocking and sets up the interrupt to act on the data FIFO, ensure there will be no another instance of the function called before the current instance has completed execution.

note

If the user provides a NULL pointer in this function and does not handle the FIFO transaction, this could either stall or timeout the operation. The transfer statuses returned by Cy_SMIF_GetTransferStatus are no longer valid.

note

Check Rules for PSoC6 QSPI/SMIF Block Usage for any usage restriction

Return

A status of a reception.

Parameters
  • base: Holds the base address of the SMIF block registers.

  • rxBuffer: The pointer to the variable where the receive data is stored. If this pointer is a NULL, then the function does not enable the interrupt. This use case is typically used when the FIFO is handled outside the interrupt and is managed in either a polling-based code or a DMA. The user would handle the FIFO management in a DMA or a polling-based code.

Parameters
  • size: The size of data to be received. Must be > 0 and not greater than 65536.

  • transferWidth: The width of transfer cy_en_smif_txfr_width_t.

  • RxCompleteCb: The callback executed at the end of a reception. NULL interpreted as no callback.

  • context: Passes a configuration structure that contains the transfer parameters of the SMIF block.

cy_en_smif_status_t Cy_SMIF_ReceiveDataBlocking(SMIF_Type *base, uint8_t *rxBuffer, uint32_t size, cy_en_smif_txfr_width_t transferWidth, cy_stc_smif_context_t const *context)

This function implements the receive data phase in the memory command.

The data is received into the RX Data FIFO using the RX_COUNT command. This function blocks until completion. The function does not use the interrupts and will use CPU to monitor the FIFO status and move data accordingly. The function returns only on completion.

note

This function is to be preceded by Cy_SMIF_TransmitCommand. The slave select is de-asserted at the end of the receive. Ensure there is no another transfers.

note

If the user provides a NULL pointer in this function and does not handle the FIFO transaction, this could either stall or timeout the operation. The transfer statuses returned by Cy_SMIF_GetTransferStatus are no longer valid.

note

Check Rules for PSoC6 QSPI/SMIF Block Usage for any usage restriction

Return

A status of a reception.

Parameters
  • base: Holds the base address of the SMIF block registers.

  • rxBuffer: The pointer to the variable where the receive data is stored. If this pointer is a NULL, then the function does not enable the interrupt. This use case is typically used when the FIFO is handled outside the interrupt and is managed in either a polling-based code or a DMA. The user would handle the FIFO management in a DMA or a polling-based code.

Parameters
  • size: The size of data to be received. Must be > 0 and not greater than 65536.

  • transferWidth: The width of transfer cy_en_smif_txfr_width_t.

  • context: Passes a configuration structure that contains the transfer parameters of the SMIF block.

cy_en_smif_status_t Cy_SMIF_SendDummyCycles(SMIF_Type *base, uint32_t cycles)

This function sends dummy-clock cycles.

The data lines are tri-stated during the dummy cycles.

note

This function is to be preceded by Cy_SMIF_TransmitCommand.

Return

A status of dummy cycles sending.

Parameters
  • base: Holds the base address of the SMIF block registers.

  • cycles: The number of dummy cycles. Must be > 0 and not greater than 65536.

uint32_t Cy_SMIF_GetTransferStatus(SMIF_Type const *base, cy_stc_smif_context_t const *context)

This function provides the status of the transfer.

This function is used to poll for the status of the TransmitData or receiveData function. When this function is called to determine the status of ongoing Cy_SMIF_ReceiveData() or Cy_SMIF_TransmitData(), the returned status is only valid if the functions passed a non-NULL buffer to transmit or receive respectively. If the pointer passed to Cy_SMIF_ReceiveData() or Cy_SMIF_TransmitData() is a NULL, then the code/DMA outside this driver will take care of the transfer and the Cy_GetTxfrStatus() will return an erroneous result.

Return

Returns the transfer status. cy_en_smif_txfr_status_t

Parameters
  • base: Holds the base address of the SMIF block registers.

  • context: Passes a configuration structure that contains the transfer parameters of the SMIF block.

void Cy_SMIF_Enable(SMIF_Type *base, cy_stc_smif_context_t *context)

Enables the operation of the SMIF block.

note

This function only enables the SMIF IP. The interrupts associated with the SMIF will need to be separately enabled using the interrupt driver.

Parameters
  • base: Holds the base address of the SMIF block registers.

  • context: Passes a configuration structure that contains the transfer parameters of the SMIF block.

cy_en_smif_status_t Cy_SMIF_TransmitCommand_Ext(SMIF_Type *base, uint16_t cmd, bool isCommand2byte, cy_en_smif_txfr_width_t cmdTxfrWidth, cy_en_smif_data_rate_t cmdDataRate, uint8_t const cmdParam[], uint32_t paramSize, cy_en_smif_txfr_width_t paramTxfrWidth, cy_en_smif_data_rate_t paramDataRate, cy_en_smif_slave_select_t slaveSelect, uint32_t cmpltTxfr, cy_stc_smif_context_t const *context)

This function transmits a command byte followed by a parameter which is typically an address field.

The transfer is implemented using the TX FIFO. This function also asserts the slave select line. A command to a memory device generally starts with a command byte transmission. This function sets up the slave lines for the rest of the command structure. The Cy_SMIF_TransmitCommand_Ext is called before Cy_SMIF_TransmitData_Ext or Cy_SMIF_ReceiveData_Ext is called. When enabled, the completeTxfr parameter in the function will de-assert the slave select line at the end of the function execution.

note

This function blocks until all the command and associated parameters have been transmitted over the SMIF block or timeout expire.

note

This API is available for CAT1B devices.

Return

A status of the command transmit.

Parameters
  • base: Holds the base address of the SMIF block registers.

  • cmd: The command byte to be transmitted.

  • isCommand2byte: isCommand2byte

  • cmdTxfrWidth: The width of command byte transfer cy_en_smif_txfr_width_t.

  • cmdDataRate: cmdDataRate

  • cmdParam: This is the pointer to an array that has bytes to be transmitted after the command byte. Typically, this field has the address bytes associated with the memory command.

  • paramSize: The size of the cmdParam array.

  • paramTxfrWidth: The width of parameter transfer cy_en_smif_txfr_width_t.

  • paramDataRate: paramDataRate

  • slaveSelect: Denotes the number of the slave device to which the transfer is made. (0, 1, 2 or 4 - the bit defines which slave to enable) Two-bit enable is possible only for the Double Quad SPI mode.

  • completeTxfr: Specifies if the slave select line must be de-asserted after transferring the last byte in the parameter array. Typically, this field is set to 0 when this function succeed through Cy_SMIF_TransmitData_Ext or Cy_SMIF_ReceiveData_Ext.

  • context: Passes a configuration structure that contains the transfer parameters of the SMIF block.

cy_en_smif_status_t Cy_SMIF_TransmitData_Ext(SMIF_Type *base, uint8_t const *txBuffer, uint32_t size, cy_en_smif_txfr_width_t transferWidth, cy_en_smif_data_rate_t dataDataRate, cy_smif_event_cb_t TxCmpltCb, cy_stc_smif_context_t *context)

This function is used to transmit data using the SMIF interface.

This function uses the TX Data FIFO to implement the transmit functionality. The function sets up an interrupt to trigger the TX Data FIFO and uses that interrupt to fill the TX Data FIFO until all the data is transmitted. At the end of the transmission, the TxCmpltCb is executed.

note

This function is to be preceded by Cy_SMIF_TransmitCommand_Ext where the slave select is selected. The slave is de-asserted at the end of a transmit. The function triggers the transfer and the transfer itself utilizes the interrupt for FIFO operations in the background. Thus, frequent interrupts will be executed after this function is triggered. Since this API is non-blocking and sets up the interrupt to act on the data FIFO, ensure there will be no another instance of the function called before the current instance has completed execution.

note

If the user provides a NULL pointer in this function and does not handle the FIFO transaction, this could either stall or timeout the operation. The transfer statuses returned by Cy_SMIF_GetTransferStatus are no longer valid.

note

This API is available for CAT1B devices.

Return

A status of a transmission.

Parameters
  • base: Holds the base address of the SMIF block registers.

  • txBuffer: The pointer to the data to be transferred. If this pointer is a NULL, then the function does not enable the interrupt. This use case is typically used when the FIFO is handled outside the interrupt and is managed in either a polling-based code or a DMA. The user would handle the FIFO management in a DMA or a polling-based code.

Parameters
  • size: The size of txBuffer. Must be > 0 and not greater than 65536.

  • transferWidth: The width of transfer cy_en_smif_txfr_width_t.

  • dataDataRate: dataDataRate

  • TxCmpltCb: The callback executed at the end of a transmission. NULL interpreted as no callback.

  • context: Passes a configuration structure that contains the transfer parameters of the SMIF block.

cy_en_smif_status_t Cy_SMIF_TransmitDataBlocking_Ext(SMIF_Type *base, uint8_t const *txBuffer, uint32_t size, cy_en_smif_txfr_width_t transferWidth, cy_en_smif_data_rate_t dataRate, cy_stc_smif_context_t const *context)

This function implements the transmit data phase in the memory command.

The data is transmitted using the Tx Data FIFO and the TX_COUNT command. This function blocks until completion. The function does not use the interrupts and will use CPU to monitor the FIFO status and move data accordingly. The function returns only on completion.

note

Since this API is blocking, ensure that other transfers finished and it will not be called during non-blocking transfer.

note

If the user provides a NULL pointer in this function and does not handle the FIFO transaction, this could either stall or timeout the operation. The transfer statuses returned by Cy_SMIF_GetTransferStatus are no longer valid.

note

This API is available for CAT1B devices.

Return

A status of a transmission.

Parameters
  • base: Holds the base address of the SMIF block registers.

  • txBuffer: The pointer to the data to be transferred. If this pointer is a NULL, then the function does not fill TX_FIFO. The user would handle the FIFO management in a DMA or a polling-based code.

Parameters
  • size: The size of txBuffer. Must be > 0 and not greater than 65536.

  • transferWidth: The width of transfer cy_en_smif_txfr_width_t.

  • dataDataRate: dataDataRate

  • context: Passes a configuration structure that contains the transfer parameters of the SMIF block.

cy_en_smif_status_t Cy_SMIF_ReceiveData_Ext(SMIF_Type *base, uint8_t *rxBuffer, uint32_t size, cy_en_smif_txfr_width_t transferWidth, cy_en_smif_data_rate_t dataRate, cy_smif_event_cb_t RxCmpltCb, cy_stc_smif_context_t *context)

This function implements the receive data phase in the memory command.

The data is received into the RX Data FIFO using the RX_COUNT command. This function sets up the interrupt to trigger on the RX Data FIFO level, and the data is fetched from the RX Data FIFO to the rxBuffer as it gets filled. This function does not block until completion. The completion will trigger the call back function.

note

This function is to be preceded by Cy_SMIF_TransmitCommand. The slave select is de-asserted at the end of the receive. The function triggers the transfer and the transfer itself utilizes the interrupt for FIFO operations in the background. Thus, frequent interrupts will be executed after this function is triggered. This API is non-blocking and sets up the interrupt to act on the data FIFO, ensure there will be no another instance of the function called before the current instance has completed execution.

note

If the user provides a NULL pointer in this function and does not handle the FIFO transaction, this could either stall or timeout the operation. The transfer statuses returned by Cy_SMIF_GetTransferStatus are no longer valid.

note

Check Rules for PSoC6 QSPI/SMIF Block Usage for any usage restriction

note

This API is available for CAT1B devices.

Return

A status of a reception.

Parameters
  • base: Holds the base address of the SMIF block registers.

  • rxBuffer: The pointer to the variable where the receive data is stored. If this pointer is a NULL, then the function does not enable the interrupt. This use case is typically used when the FIFO is handled outside the interrupt and is managed in either a polling-based code or a DMA. The user would handle the FIFO management in a DMA or a polling-based code.

Parameters
  • size: The size of data to be received. Must be > 0 and not greater than 65536.

  • transferWidth: The width of transfer cy_en_smif_txfr_width_t.

  • dataRate: dataRate

  • RxCmpltCb: The callback executed at the end of a reception. NULL interpreted as no callback.

  • context: Passes a configuration structure that contains the transfer parameters of the SMIF block.

cy_en_smif_status_t Cy_SMIF_ReceiveDataBlocking_Ext(SMIF_Type *base, uint8_t *rxBuffer, uint32_t size, cy_en_smif_txfr_width_t transferWidth, cy_en_smif_data_rate_t dataRate, cy_stc_smif_context_t const *context)

This function implements the receive data phase in the memory command.

The data is received into the RX Data FIFO using the RX_COUNT command. This function blocks until completion. The function does not use the interrupts and will use CPU to monitor the FIFO status and move data accordingly. The function returns only on completion.

note

This function is to be preceded by Cy_SMIF_TransmitCommand. The slave select is de-asserted at the end of the receive. Ensure there is no another transfers.

note

If the user provides a NULL pointer in this function and does not handle the FIFO transaction, this could either stall or timeout the operation. The transfer statuses returned by Cy_SMIF_GetTransferStatus are no longer valid.

note

Check Rules for PSoC6 QSPI/SMIF Block Usage for any usage restriction

note

This API is available for CAT1B devices.

Return

A status of a reception.

Parameters
  • base: Holds the base address of the SMIF block registers.

  • rxBuffer: The pointer to the variable where the receive data is stored. If this pointer is a NULL, then the function does not enable the interrupt. This use case is typically used when the FIFO is handled outside the interrupt and is managed in either a polling-based code or a DMA. The user would handle the FIFO management in a DMA or a polling-based code.

Parameters
  • size: The size of data to be received. Must be > 0 and not greater than 65536.

  • transferWidth: The width of transfer cy_en_smif_txfr_width_t.

  • dataRate: dataRate

  • context: Passes a configuration structure that contains the transfer parameters of the SMIF block.

cy_en_smif_status_t Cy_SMIF_SendDummyCycles_Ext(SMIF_Type *base, cy_en_smif_txfr_width_t transferWidth, cy_en_smif_data_rate_t dataRate, uint32_t cycles)

This function sends dummy-clock cycles.

The data lines are tri-stated during the dummy cycles.

note

This function is to be preceded by Cy_SMIF_TransmitCommand.

note

This API is available for CAT1B devices.

Return

A status of dummy cycles sending.

Parameters
  • base: Holds the base address of the SMIF block registers.

  • transferWidth:

  • dataRate:

  • cycles: The number of dummy cycles. Must be > 0 and not greater than 65536.

__STATIC_INLINE void Cy_SMIF_Disable (SMIF_Type *base)

Disables the operation of the SMIF block.

The SMIF block can be disabled only when it is not in the active state. Use the Cy_SMIF_BusyCheck() API to check it before calling this API.

Parameters
  • base: Holds the base address of the SMIF block registers.

__STATIC_INLINE void Cy_SMIF_SetInterruptMask (SMIF_Type *base, uint32_t interrupt)

This function is used to set an interrupt mask for the SMIF Interrupt.

Parameters
  • base: Holds the base address of the SMIF block registers.

  • interrupt: This is the mask for different source options that can be masked. See Interrupt Macros for possible values.

__STATIC_INLINE uint32_t Cy_SMIF_GetInterruptMask (SMIF_Type const *base)

This function is used to read an interrupt mask for the SMIF Interrupt.

Return

Returns the mask set for the SMIF interrupt.

Parameters
  • base: Holds the base address of the SMIF block registers.

__STATIC_INLINE uint32_t Cy_SMIF_GetInterruptStatusMasked (SMIF_Type const *base)

This function is used to read an active masked interrupt.

This function can be used in the interrupt service-routine to find which source triggered the interrupt.

Return

Returns a word with bits set at positions corresponding to the interrupts triggered in the system.

Parameters
  • base: Holds the base address of the SMIF block registers.

__STATIC_INLINE uint32_t Cy_SMIF_GetInterruptStatus (SMIF_Type const *base)

This function is used to read an active interrupt.

This status is the unmasked result, so will also show interrupts that will not generate active interrupts.

Return

Returns a word with bits set at positions corresponding to the interrupts triggered in the system.

Parameters
  • base: Holds the base address of the SMIF block registers.

__STATIC_INLINE void Cy_SMIF_SetInterrupt (SMIF_Type *base, uint32_t interrupt)

This function is used to set an interrupt source.

This function can be used to activate interrupts through the software.

note

Interrupt sources set using this interrupt will generate interrupts only if they are not masked.

Parameters
  • base: Holds the base address of the SMIF block registers.

  • interrupt: An encoded integer with a bit set corresponding to the interrupt to be triggered. See Interrupt Macros for possible values.

__STATIC_INLINE void Cy_SMIF_ClearInterrupt (SMIF_Type *base, uint32_t interrupt)

This function is used to clear an interrupt source.

This function can be used in the user code to clear all pending interrupts.

Parameters
  • base: Holds the base address of the SMIF block registers.

  • interrupt: An encoded integer with a bit set corresponding to the interrupt that must be cleared. See Interrupt Macros for possible values.

__STATIC_INLINE void Cy_SMIF_SetTxFifoTriggerLevel (SMIF_Type *base, uint32_t level)

This function is used to set a trigger level for the TX FIFO.

This value must be an integer between 0 and 7. For the normal mode only. The triggering is active when TX_DATA_FIFO_STATUS <= level.

Parameters
  • base: Holds the base address of the SMIF block registers.

  • level: The trigger level to set (0-8).

__STATIC_INLINE void Cy_SMIF_SetRxFifoTriggerLevel (SMIF_Type *base, uint32_t level)

This function is used to set a trigger level for the RX FIFO.

This value must be an integer between 0 and 7. For the normal mode only. The triggering is active when RX_DATA_FIFOSTATUS > level.

Parameters
  • base: Holds the base address of the SMIF block registers.

  • level: The trigger level to set(0-8).

__STATIC_INLINE uint32_t Cy_SMIF_GetCmdFifoStatus (SMIF_Type const *base)

This function is used to read the status of the CMD FIFO.

Return

Returns the number of the entries in the CMD FIFO.

Parameters
  • base: Holds the base address of the SMIF block registers.

__STATIC_INLINE uint32_t Cy_SMIF_GetTxFifoStatus (SMIF_Type const *base)

This function is used to read the status of the TX FIFO.

Return

Returns the number of the entries in the TX FIFO.

Parameters
  • base: Holds the base address of the SMIF block registers.

__STATIC_INLINE uint32_t Cy_SMIF_GetRxFifoStatus (SMIF_Type const *base)

This function is used to read the status of the RX FIFO.

Return

Returns the number of the entries in the RX FIFO.

Parameters
  • base: Holds the base address of the SMIF block registers.

cy_en_smif_status_t Cy_SMIF_Encrypt(SMIF_Type *base, uint32_t address, uint8_t data[], uint32_t size, cy_stc_smif_context_t const *context)

Uses the Encryption engine to create an encrypted result when the input, key and data arrays are provided.

The AES-128 encryption of the address with the key, fetching the result and XOR with the data array are all done in the function. The operational scheme is the following: data = XOR(AES128(address, key), data) Decryption is done using the input data-array identically to the encryption. In the XIP mode, encryption and decryption are done without calling this function. The operational scheme in the XIP mode is the same. The address parameter in the XIP mode equals the actual address in the PSoC memory map. The SMIF encryption engine is designed for code storage. For data storage, the encryption key can be changed. For sensitive data, the Crypto block is used.

note

The API does not have access to the encryption key. The key must be placed in the register before calling this API. The crypto routine that can access the key storage area is recommended. This crypto routine is typically a protection context 0 function.

note

This is a blocking API. The API waits for encryption completion. Will exit if a timeout is set (not equal to 0) and expired.

Return

A status of the command transmit.

Function Usage

    /* Scenario:  Encrypt data in the txBuffer[] before writing data into the memory at the address=0x2000. */

    cy_stc_smif_context_t SMIF_context;  /* This is a shared context structure.
                                          * It must be global
                                          */

    #define MEMTEST_AES_KEY_SIZE (16U)   /* The AES key length */
    #define PACKET_SIZE          (32U)   /* The memory Read/Write packet */

    /* Data to encrypt */
    uint8_t txBuffer[PACKET_SIZE] = {1U, 2U, 3U, 4U, 5U, 6U, 7U, 8U,
                                     9U, 10U, 11U, 12U, 13U, 14U, 15U, 16U,
                                     17U, 18U, 19U, 20U, 21U, 22U, 23U, 24U,
                                     25U, 26U, 27U, 28U, 29U, 30U, 31U, 32U};
    uint32_t address = 0x2000UL;  /* The address to write data to  */

    /* The AES key.
    * Writing of the AES key should be from secure area of the code   
    */
    uint8_t key[MEMTEST_AES_KEY_SIZE] = {0x54U, 0x68U, 0x61U, 0x74U, 0x73U, 0x20U, 0x6DU, 0x79U,
                                         0x20U, 0x4BU, 0x75U, 0x6EU, 0x67U, 0x20U, 0x46U, 0x75U};

    /* Fill the key field in secure area of the code. */
    SMIF->CRYPTO_KEY0 = Cy_SMIF_PackBytesArray(&key[CY_SMIF_CRYPTO_FIRST_WORD], true);
    SMIF->CRYPTO_KEY1 = Cy_SMIF_PackBytesArray(&key[CY_SMIF_CRYPTO_SECOND_WORD], true);
    SMIF->CRYPTO_KEY2 = Cy_SMIF_PackBytesArray(&key[CY_SMIF_CRYPTO_THIRD_WORD], true);
    SMIF->CRYPTO_KEY3 = Cy_SMIF_PackBytesArray(&key[CY_SMIF_CRYPTO_FOURTH_WORD], true);

    /* Encrypt data in txBuffer */
    if (CY_SMIF_SUCCESS != Cy_SMIF_Encrypt(SMIF, address, txBuffer, sizeof(txBuffer), &SMIF_context))
    {
        /* Insert error handling */
    }
    
    /* The second call of Cy_SMIF_Encrypt() decrypts data in txBuffer */
    if (CY_SMIF_SUCCESS != Cy_SMIF_Encrypt(SMIF, address, txBuffer, sizeof(txBuffer), &SMIF_context))
    {
        /* Insert error handling */
    }
    

Parameters
  • base: Holds the base address of the SMIF block registers.

  • address: The address that gets encrypted is a masked 16-byte block address. The 32-bit address with the last 4 bits masked is placed as the last 4 bytes in the 128-bit input. The rest of the higher bit for the 128 bits are padded zeros. PA[127:0]: PA[3:0] = 0 PA[7:4] = ADDR[7:4]. PA[15:8] = ADDR[15:8]. PA[23:16] = ADDR[23:16]. PA[31:24] = ADDR[31:24]. The other twelve of the sixteen plain text address bytes of PA[127:0] are “0”: PA[127:32] = “0”.

  • data: This is the location where the input data-array is passed while the function is called. This array gets populated with the result after encryption is completed.

  • size: Provides a size of the array.

  • context: Passes a configuration structure that contains the transfer parameters of the SMIF block.

__STATIC_INLINE bool Cy_SMIF_BusyCheck (SMIF_Type const *base)

This function provides the status of the IP block (False - not busy, True - busy).

Return

Returns an IP block status.

Parameters
  • base: Holds the base address of the SMIF block registers.

__STATIC_INLINE void Cy_SMIF_Interrupt (SMIF_Type *base, cy_stc_smif_context_t *context)

The Interrupt Service Routine for the SMIF.

The interrupt code will be responsible for the FIFO operations on FIFO interrupts during ongoing transfers. The user must place a call to this interrupt function in the interrupt routine corresponding to the interrupt attached to the SMIF. If the user does not do this, will break: the functionality of all the API functions in the SMIF driver that use SMIF interrupts to affect transfers.

All the Global variables described above are used when the Software Buffer is used.

Global Variables

  • context->txBufferAddress - The pointer to the data to be transferred.

  • context->txBufferSize - The size of txBuffer.

  • context->txBufferCounter - The number of data entries left to be transferred.

Parameters
  • base: Holds the base address of the SMIF block registers.

  • context: Passes a configuration structure that contains the transfer parameters of the SMIF block.

cy_en_smif_status_t Cy_SMIF_CacheEnable(SMIF_Type *base, cy_en_smif_cache_t cacheType)

This function is used to enable the fast cache, the slow cache or both.

Return

A status of function completion.

Parameters
  • base: Holds the base address of the SMIF block registers.

  • cacheType: Holds the type of the cache to be modified. cy_en_smif_cache_t

cy_en_smif_status_t Cy_SMIF_CacheDisable(SMIF_Type *base, cy_en_smif_cache_t cacheType)

This function is used to disable the fast cache, the slow cache or both.

Return

A status of function completion.

Parameters
  • base: Holds the base address of the SMIF block registers.

  • cacheType: Holds the type of the cache to be modified. cy_en_smif_cache_t

cy_en_smif_status_t Cy_SMIF_CachePrefetchingEnable(SMIF_Type *base, cy_en_smif_cache_t cacheType)

This function is used to enable pre-fetching for the fast cache, the slow cache or both.

Return

A status of function completion.

Parameters
  • base: Holds the base address of the SMIF block registers.

  • cacheType: Holds the type of the cache to be modified. cy_en_smif_cache_t

cy_en_smif_status_t Cy_SMIF_CachePrefetchingDisable(SMIF_Type *base, cy_en_smif_cache_t cacheType)

This function is used to disable pre-fetching for the fast cache, the slow cache or both.

Return

A status of function completion.

Parameters
  • base: Holds the base address of the SMIF block registers.

  • cacheType: Holds the type of the cache to be modified. cy_en_smif_cache_t

cy_en_smif_status_t Cy_SMIF_CacheInvalidate(SMIF_Type *base, cy_en_smif_cache_t cacheType)

This function is used to invalidate/clear the fast cache, the slow cache or both.

Return

A status of function completion.

Parameters
  • base: Holds the base address of the SMIF block registers.

  • cacheType: Holds the type of the cache to be modified. cy_en_smif_cache_t