Manchester
Manchester.h
- Committer:
- hudakz
- Date:
- 2017-05-22
- Revision:
- 6:7454ad91f714
- Parent:
- 5:3b2c7e9fda3f
- Child:
- 8:c1b5893191fe
File content as of revision 6:7454ad91f714:
/* ****************************************************************************** * @file Manchester.h * @author Zoltan Hudak * @version * @date 2017-May-16 * @brief Manchester code for mbed ****************************************************************************** * @attention * * <h2><center>© COPYRIGHT(c) 2017 Zoltan Hudak <hudakz@outlook.com> * * All rights reserved. This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program. If not, see <http://www.gnu.org/licenses/>. */ /* This library implements Manchester code according to both IEEE 802.3 and G.E. Thomas' conventions. • A '0' is expressed by a high-to-low transition, a '1' by low-to-high transition in the IEEE 802.3 convention. The reverse is true in the G.E. Thomas' convention. • The transitions which signify '0' or '1' occur at the midpoint of a period. • Transitions at the start of a period are overhead and don't signify data. • Least significant bit is sent first • There is one synchronization pulse at the begin of transmission The IEEE 802.3 convention is used by default. Select a convention to be used by commenting or uncommenting the line "#define G_E_THOMAS 1" below. */ #ifndef MANCHESTER_H #define MANCHESTER_H #include "mbed.h" #include "ManchesterMsg.h" //Uncomment the following line to use G.E.Thomas' convention //#define G_E_THOMAS 1 class Manchester { enum State { IDLE, SYNCH_START, SYNCH_NEXT, SYNCH_END, SETUP, TRANSITION, COMPLETE, LISTEN, DECODE, ERROR }; public: Manchester ( PinName txPin, /* transmitter pin name */ PinName rxPin, /* receiver pin name */ uint32_t speed = 1200, /* speed in bits per second */ uint8_t tol = 25 /* pulse width tolerance (+/-) in % */ ); ~Manchester(void) { } void transmit(ManchesterMsg& msg); bool receive(ManchesterMsg& msg); private: DigitalOut _tx; // transmitter line InterruptIn _rx; // receiver line Ticker _txTicker; // transmitter ticker Timeout _timeout; // timeout (watchdog) uint32_t _midBitTime; // mid-bit time [us] uint32_t _minPulseWidth; // minimum pulse width [us] uint32_t _maxPulseWidth; // maximum pulse width [us] State _state; // state char* _data; // data array size_t _len; // data length in bytes size_t _maxLen; // maximum length void transmission(void); void reception(void); void txTimeout(void); void rxTimeout(void); }; #endif // MANCHESTER_H