Erik - / SoftSerial

Software serial, for when you are out of serial pins

Dependents:   BufferedSoftSerial neurGAI_Seeed_BLUETOOTH LPC-SD-35 ESP-WROOM-02_test ... more

SoftSerial_rx.cpp@4:c010265ed202, 2014-04-26 (annotated)

Committer:
Sissors
Date:
Sat Apr 26 20:04:49 2014 +0000
Revision:
4:c010265ed202
Parent:
3:7238e9bb74d2
Child:
6:517082212c00
IRQs added

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Sissors 0:8edaa7abe724 1 #include "SoftSerial.h"
Sissors 0:8edaa7abe724 2
Sissors 0:8edaa7abe724 3 int SoftSerial::_getc( void ) {
Sissors 1:f8b4b764ace7 4 while(!readable());
Sissors 1:f8b4b764ace7 5 out_valid = false;
Sissors 1:f8b4b764ace7 6 return out_buffer;
Sissors 1:f8b4b764ace7 7 }
Sissors 0:8edaa7abe724 8
Sissors 1:f8b4b764ace7 9 int SoftSerial::readable(void) {
Sissors 1:f8b4b764ace7 10 return out_valid;
Sissors 1:f8b4b764ace7 11 }
Sissors 1:f8b4b764ace7 12
Sissors 1:f8b4b764ace7 13 //Start receiving byte
Sissors 0:8edaa7abe724 14 void SoftSerial::rx_gpio_irq_handler(void) {
Sissors 3:7238e9bb74d2 15 rxout.attach_us(this, &SoftSerial::rx_handler, bit_period + (bit_period >> 1)); //Start reading first data byte
Sissors 1:f8b4b764ace7 16 rx->fall(NULL);
Sissors 1:f8b4b764ace7 17 rx_bit = 0;
Sissors 1:f8b4b764ace7 18 rx_error = false;
Sissors 0:8edaa7abe724 19 };
Sissors 1:f8b4b764ace7 20
Sissors 1:f8b4b764ace7 21 void SoftSerial::rx_handler(void) {
Sissors 3:7238e9bb74d2 22 if (!rx_bit)
Sissors 3:7238e9bb74d2 23 rxticker.attach_us(this, &SoftSerial::rx_handler, bit_period);
Sissors 3:7238e9bb74d2 24
Sissors 1:f8b4b764ace7 25 rx_bit++;
Sissors 1:f8b4b764ace7 26
Sissors 1:f8b4b764ace7 27 //Receive data
Sissors 1:f8b4b764ace7 28 int val = rx->read();
Sissors 1:f8b4b764ace7 29 if (rx_bit <= _bits) {
Sissors 1:f8b4b764ace7 30 read_buffer |= val << (rx_bit - 1);
Sissors 1:f8b4b764ace7 31 return;
Sissors 1:f8b4b764ace7 32 }
Sissors 1:f8b4b764ace7 33
Sissors 1:f8b4b764ace7 34 //Receive parity
Sissors 1:f8b4b764ace7 35 bool parity_count;
Sissors 1:f8b4b764ace7 36 if (rx_bit == _bits + 1) {
Sissors 1:f8b4b764ace7 37 switch (_parity) {
Sissors 1:f8b4b764ace7 38 case Forced1:
Sissors 1:f8b4b764ace7 39 if (val == 0)
Sissors 1:f8b4b764ace7 40 rx_error = true;
Sissors 1:f8b4b764ace7 41 return;
Sissors 1:f8b4b764ace7 42 case Forced0:
Sissors 1:f8b4b764ace7 43 if (val == 1)
Sissors 1:f8b4b764ace7 44 rx_error = true;
Sissors 1:f8b4b764ace7 45 return;
Sissors 1:f8b4b764ace7 46 case Even:
Sissors 1:f8b4b764ace7 47 case Odd:
Sissors 1:f8b4b764ace7 48 parity_count = val;
Sissors 1:f8b4b764ace7 49 for (int i = 0; i<_bits; i++) {
Sissors 1:f8b4b764ace7 50 if (((read_buffer >> i) & 0x01) == 1)
Sissors 1:f8b4b764ace7 51 parity_count = !parity_count;
Sissors 1:f8b4b764ace7 52 }
Sissors 1:f8b4b764ace7 53 if ((parity_count) && (_parity == Even))
Sissors 1:f8b4b764ace7 54 rx_error = true;
Sissors 1:f8b4b764ace7 55 if ((!parity_count) && (_parity == Odd))
Sissors 1:f8b4b764ace7 56 rx_error = true;
Sissors 1:f8b4b764ace7 57 return;
Sissors 1:f8b4b764ace7 58 }
Sissors 1:f8b4b764ace7 59 }
Sissors 1:f8b4b764ace7 60
Sissors 1:f8b4b764ace7 61 //Receive stop
Sissors 1:f8b4b764ace7 62 if (rx_bit < _bits + (bool)_parity + _stop_bits) {
Sissors 1:f8b4b764ace7 63 if (!val)
Sissors 1:f8b4b764ace7 64 rx_error = true;
Sissors 1:f8b4b764ace7 65 return;
Sissors 1:f8b4b764ace7 66 }
Sissors 1:f8b4b764ace7 67
Sissors 1:f8b4b764ace7 68 //The last stop bit
Sissors 1:f8b4b764ace7 69 if (!val)
Sissors 1:f8b4b764ace7 70 rx_error = true;
Sissors 1:f8b4b764ace7 71
Sissors 1:f8b4b764ace7 72 if (!rx_error) {
Sissors 1:f8b4b764ace7 73 out_valid = true;
Sissors 1:f8b4b764ace7 74 out_buffer = read_buffer;
Sissors 4:c010265ed202 75 fpointer[RxIrq].call();
Sissors 1:f8b4b764ace7 76 }
Sissors 1:f8b4b764ace7 77 read_buffer = 0;
Sissors 3:7238e9bb74d2 78 rxticker.detach();
Sissors 1:f8b4b764ace7 79 rx->fall(this, &SoftSerial::rx_gpio_irq_handler);
Sissors 1:f8b4b764ace7 80 }
Sissors 1:f8b4b764ace7 81