Mbed OS Reference | serial_api.h Source File

 
 /** \addtogroup hal */
 /** @{*/
 /* mbed Microcontroller Library
  * Copyright (c) 2006-2013 ARM Limited
  * SPDX-License-Identifier: Apache-2.0
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *     http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
 #ifndef MBED_SERIAL_API_H
 #define MBED_SERIAL_API_H
 
 #include "device.h"
 #include "pinmap.h"
 #include "hal/buffer.h"
 #include "hal/dma_api.h"
 
 #if DEVICE_SERIAL
 
 #define SERIAL_EVENT_TX_SHIFT (2)
 #define SERIAL_EVENT_RX_SHIFT (8)
 
 #define SERIAL_EVENT_TX_MASK (0x00FC)
 #define SERIAL_EVENT_RX_MASK (0x3F00)
 
 #define SERIAL_EVENT_ERROR (1 << 1)
 
 /**
  * @defgroup SerialTXEvents Serial TX Events Macros
  *
  * @{
  */
 #define SERIAL_EVENT_TX_COMPLETE (1 << (SERIAL_EVENT_TX_SHIFT + 0))
 #define SERIAL_EVENT_TX_ALL      (SERIAL_EVENT_TX_COMPLETE)
 /**@}*/
 
 /**
  * @defgroup SerialRXEvents Serial RX Events Macros
  *
  * @{
  */
 #define SERIAL_EVENT_RX_COMPLETE        (1 << (SERIAL_EVENT_RX_SHIFT + 0))
 #define SERIAL_EVENT_RX_OVERRUN_ERROR   (1 << (SERIAL_EVENT_RX_SHIFT + 1))
 #define SERIAL_EVENT_RX_FRAMING_ERROR   (1 << (SERIAL_EVENT_RX_SHIFT + 2))
 #define SERIAL_EVENT_RX_PARITY_ERROR    (1 << (SERIAL_EVENT_RX_SHIFT + 3))
 #define SERIAL_EVENT_RX_OVERFLOW        (1 << (SERIAL_EVENT_RX_SHIFT + 4))
 #define SERIAL_EVENT_RX_CHARACTER_MATCH (1 << (SERIAL_EVENT_RX_SHIFT + 5))
 #define SERIAL_EVENT_RX_ALL             (SERIAL_EVENT_RX_OVERFLOW | SERIAL_EVENT_RX_PARITY_ERROR | \
                                          SERIAL_EVENT_RX_FRAMING_ERROR | SERIAL_EVENT_RX_OVERRUN_ERROR | \
                                          SERIAL_EVENT_RX_COMPLETE | SERIAL_EVENT_RX_CHARACTER_MATCH)
 /**@}*/
 
 #define SERIAL_RESERVED_CHAR_MATCH (255)
 
 typedef enum {
     ParityNone = 0,
     ParityOdd = 1,
     ParityEven = 2,
     ParityForced1 = 3,
     ParityForced0 = 4
 } SerialParity;
 
 /** Serial interrupt sources
  */
 typedef enum {
     RxIrq,      /**< Receive Data Register Full */
     TxIrq       /**< Transmit Data Register Empty */
 } SerialIrq;
 
 typedef enum {
     FlowControlNone,
     FlowControlRTS,
     FlowControlCTS,
     FlowControlRTSCTS
 } FlowControl;
 
 typedef void (*uart_irq_handler)(uint32_t id, SerialIrq event);
 
 #if DEVICE_SERIAL_ASYNCH
 /** Asynch serial HAL structure
  */
 typedef struct {
     struct serial_s serial;  /**< Target specific serial structure */
     struct buffer_s tx_buff; /**< TX buffer */
     struct buffer_s rx_buff; /**< RX buffer */
     uint8_t char_match;      /**< Character to be matched */
     uint8_t char_found;      /**< State of the matched character */
 } serial_t;
 
 #else
 /** Non-asynch serial HAL structure
  */
 typedef struct serial_s serial_t;
 
 #endif
 
 #ifdef __cplusplus
 extern "C" {
 #endif
 
 /**
  * \defgroup hal_GeneralSerial Serial Configuration Functions
  *
  * # Defined behavior
  * * ::serial_init initializes the ::serial_t
  * * ::serial_init sets the default parameters for serial peripheral (9600 bps, 8N1 format)
  * * ::serial_init configures the specified pins
  * * ::serial_free releases the serial peripheral
  * * ::serial_baud configures the baud rate
  * * at least 9600 bps the baud rate  must be supported
  * * ::serial_format configures the transmission format (number of bits, parity and the number of stop bits)
  * * at least 8N1 format must be supported
  * * ::serial_irq_handler registers the interrupt handler which will be invoked when the interrupt fires.
  * * ::serial_irq_set enables or disables the serial RX or TX IRQ.
  * * If `RxIrq` is enabled by ::serial_irq_set, ::serial_irq_handler will be invoked whenever
  * Receive Data Register Full IRQ is generated.
  * * If `TxIrq` is enabled by ::serial_irq_set, ::serial_irq_handler will be invoked whenever
  * Transmit Data Register Empty IRQ is generated.
  * * If the interrupt condition holds true, when the interrupt is enabled with ::serial_irq_set,
  * the ::serial_irq_handler is called instantly.
  * * ::serial_getc returns the character from serial buffer.
  * * ::serial_getc is a blocking call (waits for the character).
  * * ::serial_putc sends a character.
  * * ::serial_putc is a blocking call (waits for a peripheral to be available).
  * * ::serial_readable returns non-zero value if a character can be read, 0 otherwise.
  * * ::serial_writable returns non-zero value if a character can be written, 0 otherwise.
  * * ::serial_clear clears the ::serial_t RX/TX buffers
  * * ::serial_break_set sets the break signal.
  * * ::serial_break_clear clears the break signal.
  * * ::serial_pinout_tx configures the TX pin as an output (to be used in half-duplex mode).
  * * ::serial_set_flow_control configures serial flow control.
  * * ::serial_set_flow_control sets flow control in the hardware if a serial peripheral supports it,
  * otherwise software emulation is used.
  * * ::serial_tx_asynch starts the serial asynchronous transfer.
  * * ::serial_tx_asynch writes `tx_length` bytes from the `tx` to the bus.
  * * ::serial_tx_asynch must support 8 data bits
  * * The callback given to ::serial_tx_asynch is invoked when the transfer completes.
  * * ::serial_tx_asynch specifies the logical OR of events to be registered.
  * * The ::serial_tx_asynch function may use the `DMAUsage` hint to select the appropriate async algorithm.
  * * ::serial_rx_asynch starts the serial asynchronous transfer.
  * * ::serial_rx_asynch reads `rx_length` bytes to the `rx` buffer.
  * * ::serial_rx_asynch must support 8 data bits
  * * The callback given to ::serial_rx_asynch is invoked when the transfer completes.
  * * ::serial_rx_asynch specifies the logical OR of events to be registered.
  * * The ::serial_rx_asynch function may use the `DMAUsage` hint to select the appropriate async algorithm.
  * * ::serial_rx_asynch specifies a character in range 0-254 to be matched, 255 is a reserved value.
  * * If SERIAL_EVENT_RX_CHARACTER_MATCH event is not registered, the `char_match` is ignored.
  * * The SERIAL_EVENT_RX_CHARACTER_MATCH event is set in the callback when SERIAL_EVENT_RX_CHARACTER_MATCH event is
  * registered AND `char_match` is present in the received data.
  * * ::serial_tx_active returns non-zero if the TX transaction is ongoing, 0 otherwise.
  * * ::serial_rx_active returns non-zero if the RX transaction is ongoing, 0 otherwise.
  * * ::serial_irq_handler_asynch returns event flags if a transfer termination condition was met, otherwise returns 0.
  * * ::serial_irq_handler_asynch takes no longer than one packet transfer time (packet_bits / baudrate) to execute.
  * * ::serial_tx_abort_asynch aborts the ongoing TX transaction.
  * * ::serial_tx_abort_asynch disables the enabled interupt for TX.
  * * ::serial_tx_abort_asynch flushes the TX hardware buffer if TX FIFO is used.
  * * ::serial_rx_abort_asynch aborts the ongoing RX transaction.
  * * ::serial_rx_abort_asynch disables the enabled interupt for RX.
  * * ::serial_rx_abort_asynch flushes the TX hardware buffer if RX FIFO is used.
  * * Correct operation guaranteed when interrupt latency is shorter than one packet transfer time (packet_bits / baudrate)
  * if the flow control is not used.
  * * Correct operation guaranteed regardless of interrupt latency if the flow control is used.
  *
  * # Undefined behavior
  * * Calling ::serial_init multiple times on the same `serial_t` without ::serial_free.
  * * Passing invalid pin to ::serial_init, ::serial_pinout_tx.
  * * Calling any function other than ::serial_init on am uninitialized or freed `serial_t`.
  * * Passing an invalid pointer as `obj` to any function.
  * * Passing an invalid pointer as `handler` to ::serial_irq_handler, ::serial_tx_asynch, ::serial_rx_asynch.
  * * Calling ::serial_tx_abort while no async TX transfer is being processed.
  * * Calling ::serial_rx_abort while no async RX transfer is being processed.
  * * Devices behavior is undefined when the interrupt latency is longer than one packet transfer time
  * (packet_bits / baudrate) if the flow control is not used.
  * @{
  */
 
 /**
  * \defgroup hal_GeneralSerial_tests Serial hal tests
  * The Serial HAL tests ensure driver conformance to defined behavior.
  *
  * To run the Serial hal tests use the command:
  *
  *     mbed test -t <toolchain> -m <target> -n tests-mbed_hal_fpga_ci_test_shield-uart
  *
  */
 
 /** Initialize the serial peripheral. It sets the default parameters for serial
  *  peripheral, and configures its specifieds pins.
  *
  * @param obj The serial object
  * @param tx  The TX pin name
  * @param rx  The RX pin name
  */
 void serial_init(serial_t *obj, PinName tx, PinName rx);
 
 /** Release the serial peripheral, not currently invoked. It requires further
  *  resource management.
  *
  * @param obj The serial object
  */
 void serial_free(serial_t *obj);
 
 /** Configure the baud rate
  *
  * @param obj      The serial object
  * @param baudrate The baud rate to be configured
  */
 void serial_baud(serial_t *obj, int baudrate);
 
 /** Configure the format. Set the number of bits, parity and the number of stop bits
  *
  * @param obj       The serial object
  * @param data_bits The number of data bits
  * @param parity    The parity
  * @param stop_bits The number of stop bits
  */
 void serial_format(serial_t *obj, int data_bits, SerialParity parity, int stop_bits);
 
 /** The serial interrupt handler registration
  *
  * @param obj     The serial object
  * @param handler The interrupt handler which will be invoked when the interrupt fires
  * @param id      The SerialBase object
  */
 void serial_irq_handler(serial_t *obj, uart_irq_handler handler, uint32_t id);
 
 /** Configure serial interrupt. This function is used for word-approach
  *
  * @param obj    The serial object
  * @param irq    The serial IRQ type (RX or TX)
  * @param enable Set to non-zero to enable events, or zero to disable them
  */
 void serial_irq_set(serial_t *obj, SerialIrq irq, uint32_t enable);
 
 /** Get character. This is a blocking call, waiting for a character
  *
  * @param obj The serial object
  */
 int  serial_getc(serial_t *obj);
 
 /** Send a character. This is a blocking call, waiting for a peripheral to be available
  *  for writing
  *
  * @param obj The serial object
  * @param c   The character to be sent
  */
 void serial_putc(serial_t *obj, int c);
 
 /** Check if the serial peripheral is readable
  *
  * @param obj The serial object
  * @return Non-zero value if a character can be read, 0 if nothing to read
  */
 int  serial_readable(serial_t *obj);
 
 /** Check if the serial peripheral is writable
  *
  * @param obj The serial object
  * @return Non-zero value if a character can be written, 0 otherwise.
  */
 int  serial_writable(serial_t *obj);
 
 /** Clear the serial peripheral
  *
  * @param obj The serial object
  */
 void serial_clear(serial_t *obj);
 
 /** Set the break
  *
  * @param obj The serial object
  */
 void serial_break_set(serial_t *obj);
 
 /** Clear the break
  *
  * @param obj The serial object
  */
 void serial_break_clear(serial_t *obj);
 
 /** Configure the TX pin for UART function.
  *
  * @param tx The pin name used for TX
  */
 void serial_pinout_tx(PinName tx);
 
 #if DEVICE_SERIAL_FC
 /** Configure the serial for the flow control. It sets flow control in the hardware
  *  if a serial peripheral supports it, otherwise software emulation is used.
  *
  * @param obj    The serial object
  * @param type   The type of the flow control. Look at the available FlowControl types.
  * @param rxflow The TX pin name
  * @param txflow The RX pin name
  */
 void serial_set_flow_control(serial_t *obj, FlowControl type, PinName rxflow, PinName txflow);
 #endif
 
 /** Get the pins that support Serial TX
  *
  * Return a PinMap array of pins that support Serial TX. The
  * array is terminated with {NC, NC, 0}.
  *
  * @return PinMap array
  */
 const PinMap *serial_tx_pinmap(void);
 
 /** Get the pins that support Serial RX
  *
  * Return a PinMap array of pins that support Serial RX. The
  * array is terminated with {NC, NC, 0}.
  *
  * @return PinMap array
  */
 const PinMap *serial_rx_pinmap(void);
 
 #if DEVICE_SERIAL_FC
 /** Get the pins that support Serial CTS
  *
  * Return a PinMap array of pins that support Serial CTS. The
  * array is terminated with {NC, NC, 0}.
  *
  * @return PinMap array
  */
 const PinMap *serial_cts_pinmap(void);
 
 /** Get the pins that support Serial RTS
  *
  * Return a PinMap array of pins that support Serial RTS. The
  * array is terminated with {NC, NC, 0}.
  *
  * @return PinMap array
  */
 const PinMap *serial_rts_pinmap(void);
 #endif
 
 #if DEVICE_SERIAL_ASYNCH
 
 /**@}*/
 
 /**
  * \defgroup hal_AsynchSerial Asynchronous Serial Hardware Abstraction Layer
  * @{
  */
 
 /** Begin asynchronous TX transfer. The used buffer is specified in the serial object,
  *  tx_buff
  *
  * @param obj       The serial object
  * @param tx        The transmit buffer
  * @param tx_length The number of bytes to transmit
  * @param tx_width  Deprecated argument
  * @param handler   The serial handler
  * @param event     The logical OR of events to be registered
  * @param hint      A suggestion for how to use DMA with this transfer
  * @return Returns number of data transfered, otherwise returns 0
  */
 int serial_tx_asynch(serial_t *obj, const void *tx, size_t tx_length, uint8_t tx_width, uint32_t handler, uint32_t event, DMAUsage hint);
 
 /** Begin asynchronous RX transfer (enable interrupt for data collecting)
  *  The used buffer is specified in the serial object - rx_buff
  *
  * @param obj        The serial object
  * @param rx         The receive buffer
  * @param rx_length  The number of bytes to receive
  * @param rx_width   Deprecated argument
  * @param handler    The serial handler
  * @param event      The logical OR of events to be registered
  * @param char_match A character in range 0-254 to be matched
  * @param hint       A suggestion for how to use DMA with this transfer
  */
 void serial_rx_asynch(serial_t *obj, void *rx, size_t rx_length, uint8_t rx_width, uint32_t handler, uint32_t event, uint8_t char_match, DMAUsage hint);
 
 /** Attempts to determine if the serial peripheral is already in use for TX
  *
  * @param obj The serial object
  * @return Non-zero if the RX transaction is ongoing, 0 otherwise
  */
 uint8_t serial_tx_active(serial_t *obj);
 
 /** Attempts to determine if the serial peripheral is already in use for RX
  *
  * @param obj The serial object
  * @return Non-zero if the RX transaction is ongoing, 0 otherwise
  */
 uint8_t serial_rx_active(serial_t *obj);
 
 /** The asynchronous TX and RX handler.
  *
  * @param obj The serial object
  * @return Returns event flags if an RX transfer termination condition was met; otherwise returns 0
  */
 int serial_irq_handler_asynch(serial_t *obj);
 
 /** Abort the ongoing TX transaction. It disables the enabled interupt for TX and
  *  flushes the TX hardware buffer if TX FIFO is used
  *
  * @param obj The serial object
  */
 void serial_tx_abort_asynch(serial_t *obj);
 
 /** Abort the ongoing RX transaction. It disables the enabled interrupt for RX and
  *  flushes the RX hardware buffer if RX FIFO is used
  *
  * @param obj The serial object
  */
 void serial_rx_abort_asynch(serial_t *obj);
 
 /**@}*/
 
 #endif
 
 #ifdef __cplusplus
 }
 #endif
 
 #endif
 
 #endif
 
 /** @}*/
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