Thomas Cauwelier / Mbed 2 deprecated visible_light_communication

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Dependencies:   SoftSerial SDFileSystem mbed wave_player

MySoftSerial.cpp@19:822d93e0bf34, 2017-05-10 (annotated)

Committer:
Thomas Cauwelier
Date:
Wed May 10 18:21:14 2017 +0200
Revision:
19:822d93e0bf34
Parent:
17:8683abdc1912
Child:
20:d2a8daeb6eb7
add dc correction

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Thomas Cauwelier 15:75f9bd5d7659 1 //
Thomas Cauwelier 15:75f9bd5d7659 2 // Created by thoma on 10-May-17.
Thomas Cauwelier 15:75f9bd5d7659 3 //
Thomas Cauwelier 15:75f9bd5d7659 4
Thomas Cauwelier 15:75f9bd5d7659 5 #include "MySoftSerial.h"
Thomas Cauwelier 17:8683abdc1912 6 #include "Manchester.h"
Thomas Cauwelier 15:75f9bd5d7659 7
Desertification 16:1a0589d846bf 8 MySoftSerial::MySoftSerial(PinName TX, PinName RX, const char *name) : SoftSerial(TX, RX, name) {
Thomas Cauwelier 17:8683abdc1912 9 format(16, SoftSerial::None, 1);
Thomas Cauwelier 19:822d93e0bf34 10 timer.reset();
Thomas Cauwelier 19:822d93e0bf34 11 timer.start();
Thomas Cauwelier 15:75f9bd5d7659 12 }
Thomas Cauwelier 15:75f9bd5d7659 13
Thomas Cauwelier 15:75f9bd5d7659 14 MySoftSerial::~MySoftSerial() {
Thomas Cauwelier 15:75f9bd5d7659 15
Thomas Cauwelier 15:75f9bd5d7659 16 }
Thomas Cauwelier 15:75f9bd5d7659 17
Thomas Cauwelier 15:75f9bd5d7659 18 int MySoftSerial::putc(int c) {
Thomas Cauwelier 17:8683abdc1912 19 c = Manchester::encode(c);
Thomas Cauwelier 19:822d93e0bf34 20 timer.stop();
Thomas Cauwelier 19:822d93e0bf34 21 if(timer.read_us() > max_time_between_transmission_us){
Thomas Cauwelier 19:822d93e0bf34 22 correct_dc_offset();
Thomas Cauwelier 19:822d93e0bf34 23 }
Thomas Cauwelier 15:75f9bd5d7659 24 return _putc(c);
Thomas Cauwelier 15:75f9bd5d7659 25 }
Thomas Cauwelier 15:75f9bd5d7659 26
Thomas Cauwelier 15:75f9bd5d7659 27 int MySoftSerial::getc() {
Thomas Cauwelier 19:822d93e0bf34 28 int character = _getc();
Thomas Cauwelier 19:822d93e0bf34 29 timer.reset();
Thomas Cauwelier 19:822d93e0bf34 30 timer.start();
Thomas Cauwelier 19:822d93e0bf34 31 return Manchester::decode(character);
Thomas Cauwelier 17:8683abdc1912 32 }
Thomas Cauwelier 17:8683abdc1912 33
Thomas Cauwelier 17:8683abdc1912 34 void MySoftSerial::prepare_tx(int c) {
Thomas Cauwelier 17:8683abdc1912 35
Thomas Cauwelier 17:8683abdc1912 36 SoftSerial::prepare_tx(c);
Thomas Cauwelier 15:75f9bd5d7659 37 }
Thomas Cauwelier 17:8683abdc1912 38
Thomas Cauwelier 17:8683abdc1912 39 void MySoftSerial::baud(int baudrate) {
Thomas Cauwelier 17:8683abdc1912 40 SoftSerial::baud(baudrate);
Thomas Cauwelier 17:8683abdc1912 41 }
Thomas Cauwelier 17:8683abdc1912 42
Thomas Cauwelier 17:8683abdc1912 43 int MySoftSerial::readable() {
Thomas Cauwelier 17:8683abdc1912 44 return SoftSerial::readable();
Thomas Cauwelier 17:8683abdc1912 45 }
Thomas Cauwelier 17:8683abdc1912 46
Thomas Cauwelier 17:8683abdc1912 47 int MySoftSerial::writeable() {
Thomas Cauwelier 17:8683abdc1912 48 return SoftSerial::writeable();
Thomas Cauwelier 17:8683abdc1912 49 }
Thomas Cauwelier 19:822d93e0bf34 50
Thomas Cauwelier 19:822d93e0bf34 51 void MySoftSerial::correct_dc_offset() {
Thomas Cauwelier 19:822d93e0bf34 52 for (int i = 0; i < 1; ++i) {
Thomas Cauwelier 19:822d93e0bf34 53 tx->write(0);
Thomas Cauwelier 19:822d93e0bf34 54 wait_us(bit_period * 12); // send 12 zeros
Thomas Cauwelier 19:822d93e0bf34 55 tx->write(1);
Thomas Cauwelier 19:822d93e0bf34 56 wait_us(bit_period * 4); // send 4 ones
Thomas Cauwelier 19:822d93e0bf34 57 }
Thomas Cauwelier 19:822d93e0bf34 58 }