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
Fork of BufferedSerial by
BufferedSerial.cpp@1:57a11fb5d529, 2013-05-23 (annotated)
- Committer:
- sam_grove
- Date:
- Thu May 23 23:47:04 2013 +0000
- Revision:
- 1:57a11fb5d529
- Parent:
- 0:a977d0a3d81e
- Child:
- 2:7e8a450a9101
Added prime (private member).Only want to pull from the buffer and write in one spot. prime stops irq's and call the member txIrq to put the oldest buffered byte in the transmitter. IRQ will pull the rest out once enabled again.
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
sam_grove | 0:a977d0a3d81e | 1 | /** |
sam_grove | 0:a977d0a3d81e | 2 | * @file BufferedSerial.cpp |
sam_grove | 0:a977d0a3d81e | 3 | * @brief Software Buffer - Extends mbed Serial functionallity adding irq driven TX and RX |
sam_grove | 0:a977d0a3d81e | 4 | * @author sam grove |
sam_grove | 0:a977d0a3d81e | 5 | * @version 1.0 |
sam_grove | 0:a977d0a3d81e | 6 | * @see |
sam_grove | 0:a977d0a3d81e | 7 | * |
sam_grove | 0:a977d0a3d81e | 8 | * Copyright (c) 2013 |
sam_grove | 0:a977d0a3d81e | 9 | * |
sam_grove | 0:a977d0a3d81e | 10 | * Licensed under the Apache License, Version 2.0 (the "License"); |
sam_grove | 0:a977d0a3d81e | 11 | * you may not use this file except in compliance with the License. |
sam_grove | 0:a977d0a3d81e | 12 | * You may obtain a copy of the License at |
sam_grove | 0:a977d0a3d81e | 13 | * |
sam_grove | 0:a977d0a3d81e | 14 | * http://www.apache.org/licenses/LICENSE-2.0 |
sam_grove | 0:a977d0a3d81e | 15 | * |
sam_grove | 0:a977d0a3d81e | 16 | * Unless required by applicable law or agreed to in writing, software |
sam_grove | 0:a977d0a3d81e | 17 | * distributed under the License is distributed on an "AS IS" BASIS, |
sam_grove | 0:a977d0a3d81e | 18 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
sam_grove | 0:a977d0a3d81e | 19 | * See the License for the specific language governing permissions and |
sam_grove | 0:a977d0a3d81e | 20 | * limitations under the License. |
sam_grove | 0:a977d0a3d81e | 21 | */ |
sam_grove | 0:a977d0a3d81e | 22 | |
sam_grove | 0:a977d0a3d81e | 23 | #include "BufferedSerial.h" |
sam_grove | 0:a977d0a3d81e | 24 | #include "LogUtil.h" |
sam_grove | 0:a977d0a3d81e | 25 | #include <stdarg.h> |
sam_grove | 0:a977d0a3d81e | 26 | |
sam_grove | 0:a977d0a3d81e | 27 | BufferedSerial::BufferedSerial(PinName tx, PinName rx, const char* name) |
sam_grove | 0:a977d0a3d81e | 28 | : Serial(tx, rx, name) |
sam_grove | 0:a977d0a3d81e | 29 | { |
sam_grove | 0:a977d0a3d81e | 30 | Serial::attach(this, &BufferedSerial::rxIrq, Serial::RxIrq); |
sam_grove | 0:a977d0a3d81e | 31 | Serial::attach(this, &BufferedSerial::txIrq, Serial::TxIrq); |
sam_grove | 0:a977d0a3d81e | 32 | |
sam_grove | 0:a977d0a3d81e | 33 | return; |
sam_grove | 0:a977d0a3d81e | 34 | } |
sam_grove | 0:a977d0a3d81e | 35 | |
sam_grove | 0:a977d0a3d81e | 36 | BufferedSerial::~BufferedSerial(void) |
sam_grove | 0:a977d0a3d81e | 37 | { |
sam_grove | 0:a977d0a3d81e | 38 | Serial::attach(NULL, Serial::RxIrq); |
sam_grove | 0:a977d0a3d81e | 39 | Serial::attach(NULL, Serial::TxIrq); |
sam_grove | 0:a977d0a3d81e | 40 | |
sam_grove | 0:a977d0a3d81e | 41 | return; |
sam_grove | 0:a977d0a3d81e | 42 | } |
sam_grove | 0:a977d0a3d81e | 43 | |
sam_grove | 0:a977d0a3d81e | 44 | int BufferedSerial::readable(void) |
sam_grove | 0:a977d0a3d81e | 45 | { |
sam_grove | 0:a977d0a3d81e | 46 | return _rxbuf.available(); // note: look if things are in the buffer |
sam_grove | 0:a977d0a3d81e | 47 | } |
sam_grove | 0:a977d0a3d81e | 48 | |
sam_grove | 0:a977d0a3d81e | 49 | int BufferedSerial::writeable(void) |
sam_grove | 0:a977d0a3d81e | 50 | { |
sam_grove | 0:a977d0a3d81e | 51 | return 1; // buffer allows overwriting by design, always true |
sam_grove | 0:a977d0a3d81e | 52 | } |
sam_grove | 0:a977d0a3d81e | 53 | |
sam_grove | 0:a977d0a3d81e | 54 | int BufferedSerial::getc(void) |
sam_grove | 0:a977d0a3d81e | 55 | { |
sam_grove | 0:a977d0a3d81e | 56 | return _rxbuf; // note: pulling from the buffer |
sam_grove | 0:a977d0a3d81e | 57 | } |
sam_grove | 0:a977d0a3d81e | 58 | |
sam_grove | 0:a977d0a3d81e | 59 | int BufferedSerial::putc(int c) |
sam_grove | 0:a977d0a3d81e | 60 | { |
sam_grove | 0:a977d0a3d81e | 61 | _txbuf = (char)c; |
sam_grove | 1:57a11fb5d529 | 62 | BufferedSerial::prime(); |
sam_grove | 0:a977d0a3d81e | 63 | |
sam_grove | 0:a977d0a3d81e | 64 | return c; |
sam_grove | 0:a977d0a3d81e | 65 | } |
sam_grove | 0:a977d0a3d81e | 66 | |
sam_grove | 0:a977d0a3d81e | 67 | int BufferedSerial::puts(const char *s) |
sam_grove | 0:a977d0a3d81e | 68 | { |
sam_grove | 0:a977d0a3d81e | 69 | const char *size = s; |
sam_grove | 0:a977d0a3d81e | 70 | |
sam_grove | 0:a977d0a3d81e | 71 | while(*(s) != 0) |
sam_grove | 0:a977d0a3d81e | 72 | { |
sam_grove | 0:a977d0a3d81e | 73 | _txbuf = *(s++); |
sam_grove | 0:a977d0a3d81e | 74 | } |
sam_grove | 1:57a11fb5d529 | 75 | BufferedSerial::prime(); |
sam_grove | 0:a977d0a3d81e | 76 | |
sam_grove | 0:a977d0a3d81e | 77 | return s - size; |
sam_grove | 0:a977d0a3d81e | 78 | } |
sam_grove | 0:a977d0a3d81e | 79 | |
sam_grove | 0:a977d0a3d81e | 80 | int BufferedSerial::printf(const char* format, ...) |
sam_grove | 0:a977d0a3d81e | 81 | { |
sam_grove | 0:a977d0a3d81e | 82 | char buf[256] = {0}; |
sam_grove | 0:a977d0a3d81e | 83 | int r = 0; |
sam_grove | 0:a977d0a3d81e | 84 | |
sam_grove | 0:a977d0a3d81e | 85 | va_list arg; |
sam_grove | 0:a977d0a3d81e | 86 | va_start(arg, format); |
sam_grove | 0:a977d0a3d81e | 87 | r = vsprintf(buf, format, arg); |
sam_grove | 0:a977d0a3d81e | 88 | // this may not hit the heap but should alert the user anyways |
sam_grove | 0:a977d0a3d81e | 89 | if(r > sizeof(buf)) |
sam_grove | 0:a977d0a3d81e | 90 | { |
sam_grove | 0:a977d0a3d81e | 91 | ERROR("Buffer Overwrite Occured!\n"); |
sam_grove | 0:a977d0a3d81e | 92 | } |
sam_grove | 0:a977d0a3d81e | 93 | r = BufferedSerial::puts(buf); |
sam_grove | 0:a977d0a3d81e | 94 | va_end(arg); |
sam_grove | 0:a977d0a3d81e | 95 | |
sam_grove | 0:a977d0a3d81e | 96 | return r; |
sam_grove | 0:a977d0a3d81e | 97 | } |
sam_grove | 0:a977d0a3d81e | 98 | |
sam_grove | 0:a977d0a3d81e | 99 | void BufferedSerial::rxIrq(void) |
sam_grove | 0:a977d0a3d81e | 100 | { |
sam_grove | 0:a977d0a3d81e | 101 | // read from the peripheral and see if things are available |
sam_grove | 0:a977d0a3d81e | 102 | while(serial_readable(&_serial)) |
sam_grove | 0:a977d0a3d81e | 103 | { |
sam_grove | 0:a977d0a3d81e | 104 | _rxbuf = serial_getc(&_serial); // if so load them into a buffer |
sam_grove | 0:a977d0a3d81e | 105 | } |
sam_grove | 0:a977d0a3d81e | 106 | |
sam_grove | 0:a977d0a3d81e | 107 | return; |
sam_grove | 0:a977d0a3d81e | 108 | } |
sam_grove | 0:a977d0a3d81e | 109 | |
sam_grove | 0:a977d0a3d81e | 110 | void BufferedSerial::txIrq(void) |
sam_grove | 0:a977d0a3d81e | 111 | { |
sam_grove | 0:a977d0a3d81e | 112 | // see if there is room in the hardware buffer and something is in the software buffer |
sam_grove | 0:a977d0a3d81e | 113 | while(serial_writable(&_serial) && _txbuf.available()) |
sam_grove | 0:a977d0a3d81e | 114 | { |
sam_grove | 0:a977d0a3d81e | 115 | serial_putc(&_serial, (int)_txbuf.get()); |
sam_grove | 0:a977d0a3d81e | 116 | } |
sam_grove | 0:a977d0a3d81e | 117 | |
sam_grove | 0:a977d0a3d81e | 118 | return; |
sam_grove | 0:a977d0a3d81e | 119 | } |
sam_grove | 0:a977d0a3d81e | 120 | |
sam_grove | 1:57a11fb5d529 | 121 | void BufferedSerial::prime(void) |
sam_grove | 1:57a11fb5d529 | 122 | { |
sam_grove | 1:57a11fb5d529 | 123 | __disable_irq(); // make sure not to cause contention in the irq |
sam_grove | 1:57a11fb5d529 | 124 | BufferedSerial::txIrq(); // prime the txirq to stoke transmit |
sam_grove | 1:57a11fb5d529 | 125 | __enable_irq(); |
sam_grove | 1:57a11fb5d529 | 126 | |
sam_grove | 1:57a11fb5d529 | 127 | return; |
sam_grove | 1:57a11fb5d529 | 128 | } |
sam_grove | 0:a977d0a3d81e | 129 | |
sam_grove | 0:a977d0a3d81e | 130 | |
sam_grove | 1:57a11fb5d529 | 131 |