Monkey3:
Exactly the same. Still HIGH.
Is the MAX485 module in RX or TX mode when you take the readings?
EDIT:
Using the simple test program below on a Mega
#define DE 2
#define RE 3
#define TEST 4
#define DELAY 100
void setup()
{
Serial.begin(115200);
Serial1.begin(9600);
pinMode(DE, OUTPUT);
pinMode(RE, OUTPUT);
pinMode(TEST, OUTPUT);
Serial.println("Setup End");
}
void loop()
{
Serial.println("DE/RE High");
digitalWrite(DE, HIGH);
digitalWrite(RE, HIGH);
digitalWrite(TEST, HIGH);
delay(10);
Serial1.print("Hello World");
delay(DELAY);
Serial.println("DE/RE Low");
digitalWrite(DE, LOW);
digitalWrite(RE, LOW);
digitalWrite(TEST, LOW);
delay(DELAY);
}
I get the below image on my LA. You need to put the MAX481 into receive mode to release the lines.