Difference between revisions of "RS-485 Breakout"
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(Created page with "==Overview== This is a breakout board for the RS-485 transceiver IC, which will convert a UART serial signal to RS-485. This chip is a half-duplex transceiver, so it can only ...") |
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==Usage== | ==Usage== | ||
Here is an example below illustrates how to transimit and receive data via RS-485 signal. | Here is an example below illustrates how to transimit and receive data via RS-485 signal. | ||
| + | |||
| + | ===RS485 Transmitter=== | ||
| + | |||
| + | int EN = 2; | ||
| + | void setup() | ||
| + | { | ||
| + | pinMode(EN, OUTPUT); | ||
| + | Serial.begin(19200); | ||
| + | } | ||
| + | void loop() | ||
| + | { | ||
| + | // send data | ||
| + | digitalWrite(EN, HIGH);/ | ||
| + | Serial.print('A'); | ||
| + | Serial.print('B'); | ||
| + | delay(1000); | ||
| + | } | ||
| + | |||
| + | |||
| + | ===RS485 Receiver=== | ||
| + | |||
| + | int ledPin = 13; | ||
| + | int EN = 2; | ||
| + | int val; | ||
| + | void setup() | ||
| + | { | ||
| + | pinMode(ledPin, OUTPUT); | ||
| + | pinMode(EN, OUTPUT); | ||
| + | Serial.begin(19200); | ||
| + | } | ||
| + | void loop() | ||
| + | { | ||
| + | // receive data | ||
| + | digitalWrite(EN, LOW);//使能接收 | ||
| + | val = Serial.read(); | ||
| + | if (-1 != val) { | ||
| + | if ('A' == val) { | ||
| + | digitalWrite(ledPin, HIGH); | ||
| + | delay(500); | ||
| + | digitalWrite(ledPin, LOW); | ||
| + | delay(500); | ||
| + | } | ||
| + | } | ||
| + | } | ||
Revision as of 09:11, 14 January 2013
Overview
This is a breakout board for the RS-485 transceiver IC, which will convert a UART serial signal to RS-485. This chip is a half-duplex transceiver, so it can only communicate one way at a time, but it can reach transmission speeds of up to 2.5Mbps. This board requires a very low amount of power and can operate from a single +5VDC supply.
This breakout board includes the SP3485 RS-485 transceiver, filter capacitor. We've broken out the RS-485 output to three different connections: (1) an RJ-45 connector, (2) a 3-pin 3.55mm screw terminal, and (3) a 3-pin 0.1" pitch header
Features
- Fully equipped with SP3485 RS-485 transceiver and supporting components
- Operates from a single +5V supply
- Interoperable with +5.0V logic
- RS-485 input/output broken out to RJ-45 connector, 3.5mm screw terminal, and 0.1" pitch header
- Driver/Receiver Enable connected to RTS line
- -7V to +12V Common-Mode Input Voltage Range
- Allows up to 32 transceivers on the serial bus
- Driver Output Short-Circuit Protection
Usage
Here is an example below illustrates how to transimit and receive data via RS-485 signal.
RS485 Transmitter
int EN = 2;
void setup()
{
pinMode(EN, OUTPUT);
Serial.begin(19200);
}
void loop()
{
// send data
digitalWrite(EN, HIGH);/
Serial.print('A');
Serial.print('B');
delay(1000);
}
RS485 Receiver
int ledPin = 13;
int EN = 2;
int val;
void setup()
{
pinMode(ledPin, OUTPUT);
pinMode(EN, OUTPUT);
Serial.begin(19200);
}
void loop()
{
// receive data
digitalWrite(EN, LOW);//使能接收
val = Serial.read();
if (-1 != val) {
if ('A' == val) {
digitalWrite(ledPin, HIGH);
delay(500);
digitalWrite(ledPin, LOW);
delay(500);
}
}
}
