Benjamin Hepp / BufferedSerial

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Dependencies:   Buffer

Fork of BufferedSerial by Sam Grove

BufferedSerial.cpp@12:c7947d444267, 2016-02-13 (annotated)

Committer:
bhepp
Date:
Sat Feb 13 14:14:50 2016 +0000
Revision:
12:c7947d444267
Parent:
11:779304f9c5d2
Child:
13:b4080afc8cd5
Added blocking when write buffer is full

Who changed what in which revision?

UserRevisionLine numberNew contents of line
sam_grove 0:a977d0a3d81e 1 /**
bhepp 12:c7947d444267 2 * Adapted by Benjamin Hepp (benjamin.hepp@inf.ethz.ch) to include blocking when write-buffer is full.
bhepp 12:c7947d444267 3 *
sam_grove 0:a977d0a3d81e 4 * @file BufferedSerial.cpp
sam_grove 0:a977d0a3d81e 5 * @brief Software Buffer - Extends mbed Serial functionallity adding irq driven TX and RX
sam_grove 0:a977d0a3d81e 6 * @author sam grove
sam_grove 0:a977d0a3d81e 7 * @version 1.0
sam_grove 4:2ba4d2e1f05d 8 * @see
sam_grove 0:a977d0a3d81e 9 *
sam_grove 0:a977d0a3d81e 10 * Copyright (c) 2013
sam_grove 0:a977d0a3d81e 11 *
sam_grove 0:a977d0a3d81e 12 * Licensed under the Apache License, Version 2.0 (the "License");
sam_grove 0:a977d0a3d81e 13 * you may not use this file except in compliance with the License.
sam_grove 0:a977d0a3d81e 14 * You may obtain a copy of the License at
sam_grove 0:a977d0a3d81e 15 *
sam_grove 0:a977d0a3d81e 16 * http://www.apache.org/licenses/LICENSE-2.0
sam_grove 0:a977d0a3d81e 17 *
sam_grove 0:a977d0a3d81e 18 * Unless required by applicable law or agreed to in writing, software
sam_grove 0:a977d0a3d81e 19 * distributed under the License is distributed on an "AS IS" BASIS,
sam_grove 0:a977d0a3d81e 20 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
sam_grove 0:a977d0a3d81e 21 * See the License for the specific language governing permissions and
sam_grove 0:a977d0a3d81e 22 * limitations under the License.
sam_grove 0:a977d0a3d81e 23 */
sam_grove 0:a977d0a3d81e 24
sam_grove 0:a977d0a3d81e 25 #include "BufferedSerial.h"
sam_grove 0:a977d0a3d81e 26 #include <stdarg.h>
sam_grove 0:a977d0a3d81e 27
bhepp 12:c7947d444267 28 BufferedSerial::BufferedSerial(PinName tx, PinName rx, uint32_t buf_size)
bhepp 12:c7947d444267 29 : RawSerial(tx, rx) , _rxbuf(buf_size), _txbuf(buf_size), _buffered_bytes(0)
sam_grove 0:a977d0a3d81e 30 {
sam_grove 11:779304f9c5d2 31 RawSerial::attach(this, &BufferedSerial::rxIrq, Serial::RxIrq);
ansond 10:9ee15ae3d1a3 32 this->_buf_size = buf_size;
bhepp 12:c7947d444267 33 }
bhepp 12:c7947d444267 34
bhepp 12:c7947d444267 35 BufferedSerial::BufferedSerial(PinName tx, PinName rx, int baud_rate, uint32_t buf_size)
bhepp 12:c7947d444267 36 : RawSerial(tx, rx) , _rxbuf(buf_size), _txbuf(buf_size), _buffered_bytes(0)
bhepp 12:c7947d444267 37 {
bhepp 12:c7947d444267 38 baud(baud_rate);
bhepp 12:c7947d444267 39 RawSerial::attach(this, &BufferedSerial::rxIrq, Serial::RxIrq);
bhepp 12:c7947d444267 40 this->_buf_size = buf_size;
sam_grove 0:a977d0a3d81e 41 }
sam_grove 0:a977d0a3d81e 42
sam_grove 0:a977d0a3d81e 43 BufferedSerial::~BufferedSerial(void)
sam_grove 0:a977d0a3d81e 44 {
sam_grove 11:779304f9c5d2 45 RawSerial::attach(NULL, RawSerial::RxIrq);
sam_grove 11:779304f9c5d2 46 RawSerial::attach(NULL, RawSerial::TxIrq);
sam_grove 0:a977d0a3d81e 47 }
sam_grove 0:a977d0a3d81e 48
sam_grove 0:a977d0a3d81e 49 int BufferedSerial::readable(void)
sam_grove 0:a977d0a3d81e 50 {
sam_grove 0:a977d0a3d81e 51 return _rxbuf.available(); // note: look if things are in the buffer
sam_grove 0:a977d0a3d81e 52 }
sam_grove 0:a977d0a3d81e 53
sam_grove 0:a977d0a3d81e 54 int BufferedSerial::writeable(void)
sam_grove 0:a977d0a3d81e 55 {
bhepp 12:c7947d444267 56 _buffered_bytes < this->_buf_size;
sam_grove 0:a977d0a3d81e 57 }
sam_grove 0:a977d0a3d81e 58
sam_grove 0:a977d0a3d81e 59 int BufferedSerial::getc(void)
sam_grove 0:a977d0a3d81e 60 {
sam_grove 3:6b76fcf27545 61 return _rxbuf;
sam_grove 0:a977d0a3d81e 62 }
sam_grove 0:a977d0a3d81e 63
sam_grove 0:a977d0a3d81e 64 int BufferedSerial::putc(int c)
sam_grove 0:a977d0a3d81e 65 {
bhepp 12:c7947d444267 66 // Wait for free space in buffer
bhepp 12:c7947d444267 67 while (_buffered_bytes >= this->_buf_size) {}
sam_grove 0:a977d0a3d81e 68 _txbuf = (char)c;
bhepp 12:c7947d444267 69 ++_buffered_bytes;
sam_grove 1:57a11fb5d529 70 BufferedSerial::prime();
sam_grove 4:2ba4d2e1f05d 71
sam_grove 0:a977d0a3d81e 72 return c;
sam_grove 0:a977d0a3d81e 73 }
sam_grove 0:a977d0a3d81e 74
sam_grove 0:a977d0a3d81e 75 int BufferedSerial::puts(const char *s)
sam_grove 0:a977d0a3d81e 76 {
ansond 7:6fa214b41d73 77 if (s != NULL) {
ansond 7:6fa214b41d73 78 const char* ptr = s;
bhepp 12:c7947d444267 79
bhepp 12:c7947d444267 80 while (*(ptr) != 0) {
bhepp 12:c7947d444267 81 // Wait for free space in buffer
bhepp 12:c7947d444267 82 while (_buffered_bytes >= this->_buf_size) {}
ansond 7:6fa214b41d73 83 _txbuf = *(ptr++);
bhepp 12:c7947d444267 84 ++_buffered_bytes;
ansond 7:6fa214b41d73 85 }
ansond 7:6fa214b41d73 86 _txbuf = '\n'; // done per puts definition
ansond 7:6fa214b41d73 87 BufferedSerial::prime();
bhepp 12:c7947d444267 88
ansond 7:6fa214b41d73 89 return (ptr - s) + 1;
sam_grove 0:a977d0a3d81e 90 }
ansond 7:6fa214b41d73 91 return 0;
sam_grove 0:a977d0a3d81e 92 }
sam_grove 0:a977d0a3d81e 93
sam_grove 0:a977d0a3d81e 94 int BufferedSerial::printf(const char* format, ...)
sam_grove 0:a977d0a3d81e 95 {
ansond 10:9ee15ae3d1a3 96 char buffer[this->_buf_size];
bhepp 12:c7947d444267 97 memset(buffer, 0, this->_buf_size);
sam_grove 0:a977d0a3d81e 98 int r = 0;
sam_grove 4:2ba4d2e1f05d 99
sam_grove 0:a977d0a3d81e 100 va_list arg;
sam_grove 0:a977d0a3d81e 101 va_start(arg, format);
bhepp 12:c7947d444267 102 r = vsnprintf(buffer, this->_buf_size, format, arg);
sam_grove 0:a977d0a3d81e 103 // this may not hit the heap but should alert the user anyways
ansond 10:9ee15ae3d1a3 104 if(r > this->_buf_size) {
bhepp 12:c7947d444267 105 error("%s %d buffer to small (buf_size: %d, required: %d)!\r\n", __FILE__, __LINE__, this->_buf_size, r);
ansond 7:6fa214b41d73 106 va_end(arg);
ansond 7:6fa214b41d73 107 return 0;
sam_grove 0:a977d0a3d81e 108 }
sam_grove 4:2ba4d2e1f05d 109 va_end(arg);
ansond 10:9ee15ae3d1a3 110 r = BufferedSerial::write(buffer, r);
sam_grove 4:2ba4d2e1f05d 111
sam_grove 0:a977d0a3d81e 112 return r;
sam_grove 0:a977d0a3d81e 113 }
sam_grove 0:a977d0a3d81e 114
sam_grove 2:7e8a450a9101 115 ssize_t BufferedSerial::write(const void *s, size_t length)
sam_grove 2:7e8a450a9101 116 {
ansond 7:6fa214b41d73 117 if (s != NULL && length > 0) {
ansond 7:6fa214b41d73 118 const char* ptr = (const char*)s;
ansond 7:6fa214b41d73 119 const char* end = ptr + length;
bhepp 12:c7947d444267 120
ansond 7:6fa214b41d73 121 while (ptr != end) {
bhepp 12:c7947d444267 122 // Wait for free space in buffer
bhepp 12:c7947d444267 123 while (_buffered_bytes >= this->_buf_size) {}
ansond 7:6fa214b41d73 124 _txbuf = *(ptr++);
bhepp 12:c7947d444267 125 ++_buffered_bytes;
ansond 7:6fa214b41d73 126 }
ansond 7:6fa214b41d73 127 BufferedSerial::prime();
bhepp 12:c7947d444267 128
ansond 7:6fa214b41d73 129 return ptr - (const char*)s;
sam_grove 2:7e8a450a9101 130 }
ansond 7:6fa214b41d73 131 return 0;
sam_grove 2:7e8a450a9101 132 }
sam_grove 2:7e8a450a9101 133
sam_grove 2:7e8a450a9101 134
sam_grove 0:a977d0a3d81e 135 void BufferedSerial::rxIrq(void)
sam_grove 0:a977d0a3d81e 136 {
sam_grove 3:6b76fcf27545 137 // read from the peripheral and make sure something is available
bhepp 12:c7947d444267 138 if (serial_readable(&_serial)) {
sam_grove 0:a977d0a3d81e 139 _rxbuf = serial_getc(&_serial); // if so load them into a buffer
sam_grove 0:a977d0a3d81e 140 }
sam_grove 0:a977d0a3d81e 141 }
sam_grove 0:a977d0a3d81e 142
sam_grove 0:a977d0a3d81e 143 void BufferedSerial::txIrq(void)
sam_grove 0:a977d0a3d81e 144 {
sam_grove 3:6b76fcf27545 145 // see if there is room in the hardware fifo and if something is in the software fifo
bhepp 12:c7947d444267 146 while (serial_writable(&_serial)) {
bhepp 12:c7947d444267 147 if (_txbuf.available()) {
sam_grove 4:2ba4d2e1f05d 148 serial_putc(&_serial, (int)_txbuf.get());
bhepp 12:c7947d444267 149 --_buffered_bytes;
sam_grove 4:2ba4d2e1f05d 150 }
sam_grove 0:a977d0a3d81e 151 }
sam_grove 0:a977d0a3d81e 152 }
sam_grove 0:a977d0a3d81e 153
sam_grove 1:57a11fb5d529 154 void BufferedSerial::prime(void)
sam_grove 1:57a11fb5d529 155 {
sam_grove 2:7e8a450a9101 156 // if already busy then the irq will pick this up
bhepp 12:c7947d444267 157 if (serial_writable(&_serial)) {
sam_grove 11:779304f9c5d2 158 RawSerial::attach(NULL, RawSerial::TxIrq); // make sure not to cause contention in the irq
sam_grove 3:6b76fcf27545 159 BufferedSerial::txIrq(); // only write to hardware in one place
sam_grove 11:779304f9c5d2 160 RawSerial::attach(this, &BufferedSerial::txIrq, RawSerial::TxIrq);
sam_grove 2:7e8a450a9101 161 }
sam_grove 1:57a11fb5d529 162 }
sam_grove 0:a977d0a3d81e 163
sam_grove 0:a977d0a3d81e 164