Avnet / BufferedSerial-Avnet

Inherit from Serial and use software buffers for TX and RX. This allows the UART peripherals to operate in a IRQ driven mode. Overrides most (but not all) stdio functions as Serial did

Dependencies:   Buffer

Fork of BufferedSerial by Sam Grove

BufferedSerial.h@5:4d6a311fc8bf, 2014-03-24 (annotated)

Committer:
sam_grove
Date:
Mon Mar 24 19:56:57 2014 +0000
Revision:
5:4d6a311fc8bf
Parent:
3:6b76fcf27545
Child:
6:8287e83943f0
Updated example in documentation. Tested with mbed.bld 81 and works with LPC1768, LPC11U24, KL25Z, KL46Z, KL05Z

Who changed what in which revision?

UserRevisionLine numberNew contents of line
sam_grove 0:a977d0a3d81e 1
sam_grove 0:a977d0a3d81e 2 /**
sam_grove 0:a977d0a3d81e 3 * @file BufferedSerial.h
sam_grove 0:a977d0a3d81e 4 * @brief Software Buffer - Extends mbed Serial functionallity adding irq driven TX and RX
sam_grove 0:a977d0a3d81e 5 * @author sam grove
sam_grove 0:a977d0a3d81e 6 * @version 1.0
sam_grove 0:a977d0a3d81e 7 * @see
sam_grove 0:a977d0a3d81e 8 *
sam_grove 0:a977d0a3d81e 9 * Copyright (c) 2013
sam_grove 0:a977d0a3d81e 10 *
sam_grove 0:a977d0a3d81e 11 * Licensed under the Apache License, Version 2.0 (the "License");
sam_grove 0:a977d0a3d81e 12 * you may not use this file except in compliance with the License.
sam_grove 0:a977d0a3d81e 13 * You may obtain a copy of the License at
sam_grove 0:a977d0a3d81e 14 *
sam_grove 0:a977d0a3d81e 15 * http://www.apache.org/licenses/LICENSE-2.0
sam_grove 0:a977d0a3d81e 16 *
sam_grove 0:a977d0a3d81e 17 * Unless required by applicable law or agreed to in writing, software
sam_grove 0:a977d0a3d81e 18 * distributed under the License is distributed on an "AS IS" BASIS,
sam_grove 0:a977d0a3d81e 19 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
sam_grove 0:a977d0a3d81e 20 * See the License for the specific language governing permissions and
sam_grove 0:a977d0a3d81e 21 * limitations under the License.
sam_grove 0:a977d0a3d81e 22 */
sam_grove 0:a977d0a3d81e 23
sam_grove 0:a977d0a3d81e 24 #ifndef BUFFEREDSERIAL_H
sam_grove 0:a977d0a3d81e 25 #define BUFFEREDSERIAL_H
sam_grove 0:a977d0a3d81e 26
sam_grove 0:a977d0a3d81e 27 #include "mbed.h"
sam_grove 0:a977d0a3d81e 28 #include "Buffer.h"
sam_grove 0:a977d0a3d81e 29
sam_grove 0:a977d0a3d81e 30 /** A serial port (UART) for communication with other serial devices
sam_grove 0:a977d0a3d81e 31 *
sam_grove 0:a977d0a3d81e 32 * Can be used for Full Duplex communication, or Simplex by specifying
sam_grove 0:a977d0a3d81e 33 * one pin as NC (Not Connected)
sam_grove 0:a977d0a3d81e 34 *
sam_grove 0:a977d0a3d81e 35 * Example:
sam_grove 0:a977d0a3d81e 36 * @code
sam_grove 0:a977d0a3d81e 37 * #include "mbed.h"
sam_grove 0:a977d0a3d81e 38 * #include "BufferedSerial.h"
sam_grove 0:a977d0a3d81e 39 *
sam_grove 0:a977d0a3d81e 40 * BufferedSerial pc(USBTX, USBRX);
sam_grove 0:a977d0a3d81e 41 *
sam_grove 0:a977d0a3d81e 42 * int main()
sam_grove 5:4d6a311fc8bf 43 * {
sam_grove 0:a977d0a3d81e 44 * while(1)
sam_grove 0:a977d0a3d81e 45 * {
sam_grove 0:a977d0a3d81e 46 * Timer s;
sam_grove 0:a977d0a3d81e 47 *
sam_grove 0:a977d0a3d81e 48 * s.start();
sam_grove 5:4d6a311fc8bf 49 * pc.printf("Hello World - buffered\n");
sam_grove 0:a977d0a3d81e 50 * int buffered_time = s.read_us();
sam_grove 0:a977d0a3d81e 51 * wait(0.1f); // give time for the buffer to empty
sam_grove 0:a977d0a3d81e 52 *
sam_grove 0:a977d0a3d81e 53 * s.reset();
sam_grove 5:4d6a311fc8bf 54 * printf("Hello World - blocking\n");
sam_grove 0:a977d0a3d81e 55 * int polled_time = s.read_us();
sam_grove 0:a977d0a3d81e 56 * s.stop();
sam_grove 0:a977d0a3d81e 57 * wait(0.1f); // give time for the buffer to empty
sam_grove 0:a977d0a3d81e 58 *
sam_grove 0:a977d0a3d81e 59 * pc.printf("printf buffered took %d us\n", buffered_time);
sam_grove 5:4d6a311fc8bf 60 * pc.printf("printf blocking took %d us\n", polled_time);
sam_grove 0:a977d0a3d81e 61 * wait(0.5f);
sam_grove 0:a977d0a3d81e 62 * }
sam_grove 0:a977d0a3d81e 63 * }
sam_grove 0:a977d0a3d81e 64 * @endcode
sam_grove 0:a977d0a3d81e 65 */
sam_grove 0:a977d0a3d81e 66
sam_grove 0:a977d0a3d81e 67 /**
sam_grove 0:a977d0a3d81e 68 * @class BufferedSerial
sam_grove 0:a977d0a3d81e 69 * @brief Software buffers and interrupt driven tx and rx for Serial
sam_grove 0:a977d0a3d81e 70 */
sam_grove 0:a977d0a3d81e 71 class BufferedSerial : public Serial
sam_grove 0:a977d0a3d81e 72 {
sam_grove 0:a977d0a3d81e 73 private:
sam_grove 3:6b76fcf27545 74 Buffer <char> _rxbuf;
sam_grove 3:6b76fcf27545 75 Buffer <char> _txbuf;
sam_grove 0:a977d0a3d81e 76
sam_grove 0:a977d0a3d81e 77 void rxIrq(void);
sam_grove 0:a977d0a3d81e 78 void txIrq(void);
sam_grove 1:57a11fb5d529 79 void prime(void);
sam_grove 0:a977d0a3d81e 80
sam_grove 0:a977d0a3d81e 81 public:
sam_grove 0:a977d0a3d81e 82 /** Create a BufferedSerial port, connected to the specified transmit and receive pins
sam_grove 0:a977d0a3d81e 83 * @param tx Transmit pin
sam_grove 0:a977d0a3d81e 84 * @param rx Receive pin
sam_grove 0:a977d0a3d81e 85 * @note Either tx or rx may be specified as NC if unused
sam_grove 0:a977d0a3d81e 86 */
sam_grove 0:a977d0a3d81e 87 BufferedSerial(PinName tx, PinName rx, const char* name=NULL);
sam_grove 0:a977d0a3d81e 88
sam_grove 0:a977d0a3d81e 89 /** Destroy a BufferedSerial port
sam_grove 0:a977d0a3d81e 90 */
sam_grove 0:a977d0a3d81e 91 virtual ~BufferedSerial(void);
sam_grove 0:a977d0a3d81e 92
sam_grove 0:a977d0a3d81e 93 /** Check on how many bytes are in the rx buffer
sam_grove 0:a977d0a3d81e 94 * @return 1 if something exists, 0 otherwise
sam_grove 0:a977d0a3d81e 95 */
sam_grove 0:a977d0a3d81e 96 virtual int readable(void);
sam_grove 0:a977d0a3d81e 97
sam_grove 0:a977d0a3d81e 98 /** Check to see if the tx buffer has room
sam_grove 0:a977d0a3d81e 99 * @return 1 always has room and can overwrite previous content if too small / slow
sam_grove 0:a977d0a3d81e 100 */
sam_grove 0:a977d0a3d81e 101 virtual int writeable(void);
sam_grove 0:a977d0a3d81e 102
sam_grove 0:a977d0a3d81e 103 /** Get a single byte from the BufferedSerial Port.
sam_grove 0:a977d0a3d81e 104 * Should check readable() before calling this.
sam_grove 0:a977d0a3d81e 105 * @return A byte that came in on the Serial Port
sam_grove 0:a977d0a3d81e 106 */
sam_grove 0:a977d0a3d81e 107 virtual int getc(void);
sam_grove 0:a977d0a3d81e 108
sam_grove 0:a977d0a3d81e 109 /** Write a single byte to the BufferedSerial Port.
sam_grove 0:a977d0a3d81e 110 * @param c The byte to write to the Serial Port
sam_grove 2:7e8a450a9101 111 * @return The byte that was written to the Serial Port Buffer
sam_grove 0:a977d0a3d81e 112 */
sam_grove 0:a977d0a3d81e 113 virtual int putc(int c);
sam_grove 0:a977d0a3d81e 114
sam_grove 0:a977d0a3d81e 115 /** Write a string to the BufferedSerial Port. Must be NULL terminated
sam_grove 0:a977d0a3d81e 116 * @param s The string to write to the Serial Port
sam_grove 2:7e8a450a9101 117 * @return The number of bytes written to the Serial Port Buffer
sam_grove 0:a977d0a3d81e 118 */
sam_grove 0:a977d0a3d81e 119 virtual int puts(const char *s);
sam_grove 0:a977d0a3d81e 120
sam_grove 0:a977d0a3d81e 121 /** Write a formatted string to the BufferedSerial Port.
sam_grove 0:a977d0a3d81e 122 * @param format The string + format specifiers to write to the Serial Port
sam_grove 2:7e8a450a9101 123 * @return The number of bytes written to the Serial Port Buffer
sam_grove 0:a977d0a3d81e 124 */
sam_grove 0:a977d0a3d81e 125 virtual int printf(const char* format, ...);
sam_grove 0:a977d0a3d81e 126
sam_grove 2:7e8a450a9101 127 /** Write data to the Buffered Serial Port
sam_grove 2:7e8a450a9101 128 * @param s A pointer to data to send
sam_grove 2:7e8a450a9101 129 * @param length The amount of data being pointed to
sam_grove 2:7e8a450a9101 130 * @return The number of bytes written to the Serial Port Buffer
sam_grove 2:7e8a450a9101 131 */
sam_grove 2:7e8a450a9101 132 virtual ssize_t write(const void *s, std::size_t length);
sam_grove 0:a977d0a3d81e 133 };
sam_grove 0:a977d0a3d81e 134
sam_grove 0:a977d0a3d81e 135 #endif