9.5 KiB
Arduino RS485 library
Methods
begin()
Initializes the RS485 object communication speed.
Syntax
RS485.begin(baudrate)
Parameters
- baudrate: communication speed in bits per second (baud).
Returns
None.
See also
- end()
- available()
- peek()
- read()
- write()
- flush()
- beginTransmission()
- endTransmission()
- receive()
- noReceive()
- sendBreak()
- sendBreakMicroseconds()
- setPins()
end()
Disables RS485 communication.
Syntax
RS485.end()
Parameters
None.
Returns
None.
See also
- begin()
- available()
- peek()
- read()
- write()
- flush()
- beginTransmission()
- endTransmission()
- receive()
- noReceive()
- sendBreak()
- sendBreakMicroseconds()
- setPins()
available()
Get the number of bytes (characters) available for reading from the RS485 port. This is data that already arrived and is stored in the serial receive buffer.
Syntax
RS485.available()
Parameters
None.
Returns
The number of bytes available to read.
See also
- begin()
- end()
- peek()
- read()
- write()
- flush()
- beginTransmission()
- endTransmission()
- receive()
- noReceive()
- sendBreak()
- sendBreakMicroseconds()
- setPins()
available()
Get the number of bytes (characters) available for reading from the RS485 port. This is data that already arrived and is stored in the serial receive buffer.
Syntax
RS485.available()
Parameters
None.
Returns
The number of bytes available to read.
See also
- begin()
- end()
- peek()
- read()
- write()
- flush()
- beginTransmission()
- endTransmission()
- receive()
- noReceive()
- sendBreak()
- sendBreakMicroseconds()
- setPins()
peek()
Returns the next byte (character) of the incoming serial data without removing it from the internal serial buffer. That is, successive calls to peek() will return the same character, as will the next call to read().
Syntax
RS485.peek()
Parameters
None.
Returns
The first byte of incoming serial data available or -1 if no data is available.
See also
- begin()
- end()
- available()
- read()
- write()
- flush()
- beginTransmission()
- endTransmission()
- receive()
- noReceive()
- sendBreak()
- sendBreakMicroseconds()
- setPins()
read()
Reads incoming serial data.
Syntax
RS485.read()
Parameters
None.
Returns
The first byte of incoming serial data available or -1 if no data is available.
See also
- begin()
- end()
- available()
- peak()
- write()
- flush()
- beginTransmission()
- endTransmission()
- receive()
- noReceive()
- sendBreak()
- sendBreakMicroseconds()
- setPins()
write()
Writes binary data to the serial port. This data is sent as a byte or series of bytes.
Syntax
RS485.write(uint8_t b)
Parameters
- b: unsigned char.
Returns
The number of bytes written.
See also
- begin()
- end()
- available()
- peak()
- read()
- flush()
- beginTransmission()
- endTransmission()
- receive()
- noReceive()
- sendBreak()
- sendBreakMicroseconds()
- setPins()
flush()
Waits for the transmission of outgoing serial data to complete.
Syntax
RS485.flush()
Parameters
None.
Returns
None.
See also
- begin()
- end()
- available()
- peak()
- read()
- write()
- beginTransmission()
- endTransmission()
- receive()
- noReceive()
- sendBreak()
- sendBreakMicroseconds()
- setPins()
beginTransmission()
Enables RS-485 transmission.
Syntax
RS485.beginTransmission()
Parameters
None.
Returns
None.
Example
#include <ArduinoRS485.h>
int counter = 0;
void setup() {
RS485.begin(9600);
}
void loop() {
RS485.beginTransmission();
RS485.print("Counter: ");
RS485.println(counter);
RS485.endTransmission();
counter++;
delay(1000);
}
See also
- begin()
- end()
- available()
- peak()
- read()
- write()
- flush()
- endTransmission()
- receive()
- noReceive()
- sendBreak()
- sendBreakMicroseconds()
- setPins()
endTransmission()
Disables RS-485 transmission.
Syntax
RS485.endTransmission()
Parameters
None.
Returns
None.
Example
#include <ArduinoRS485.h>
int counter = 0;
void setup() {
RS485.begin(9600);
}
void loop() {
RS485.beginTransmission();
RS485.print("Counter: ");
RS485.println(counter);
RS485.endTransmission();
counter++;
delay(1000);
}
See also
- begin()
- end()
- available()
- peak()
- read()
- write()
- flush()
- beginTransmission()
- receive()
- noReceive()
- sendBreak()
- sendBreakMicroseconds()
- setPins()
receive()
Enables reception.
Syntax
RS485.receive()
Parameters
None.
Returns
None.
Example
#include <ArduinoRS485.h>
void setup() {
Serial.begin(9600);
while (!Serial);
RS485.begin(9600);
// Enable data reception
RS485.receive();
}
void loop() {
if (RS485.available()) {
Serial.write(RS485.read());
}
}
See also
- begin()
- end()
- available()
- peak()
- read()
- write()
- flush()
- beginTransmission()
- endTransmission()
- noReceive()
- sendBreak()
- sendBreakMicroseconds()
- setPins()
noReceive()
Disables reception.
Syntax
RS485.noReceive()
Parameters
None.
Returns
None.
See also
- begin()
- end()
- available()
- peak()
- read()
- write()
- flush()
- beginTransmission()
- endTransmission()
- receive()
- sendBreak()
- sendBreakMicroseconds()
- setPins()
sendBreak()
Sends a serial break signal for the specified duration in milliseconds.
Syntax
RS485.sendBreak(unsigned int duration)
Parameters
- duration: Duration of the break signal in milliseconds.
Returns
None.
See also
- begin()
- end()
- available()
- peak()
- read()
- write()
- flush()
- beginTransmission()
- endTransmission()
- receive()
- noReceive()
- sendBreakMicroseconds()
- setPins()
sendBreakMicroseconds()
Sends a serial break signal for the specified duration in microseconds.
Syntax
RS485.sendBreak(unsigned int duration)
Parameters
- duration: Duration of the break signal in microseconds.
Returns
None.
See also
- begin()
- end()
- available()
- peak()
- read()
- write()
- flush()
- beginTransmission()
- endTransmission()
- receive()
- noReceive()
- sendBreak()
- setPins()
setPins()
Modify the pins used to communicate with the MAX3157 chipset. By default the library uses pin 14 for TX, pin A6 for drive output enable, and pin A5 for receiver output enable.
Syntax
RS485.setPins(int txPin, int dePin, int rePin)
Parameters
- txPin: transmission pin (used to send break signals).
- dePin: drive output enable pin.
- rePin: receiver output enable pin.
Returns
None.