Hello guys,
I have been working for a while to trigger an Arduino stopwatch from a video card with RS4222 port.
To do so, I have developed a tool (a plug) in order to get an easy access to the RS422 port of my video card (see picture).
Afterward, I have been working on sending an easy message from my video card through the RS422 port (see oscilloscope picture).
Then, I have been developing my Arduino StopWatch with 7 leds. It works in a binary code. I am going to 99 (1100100) and then starting from 0 again.
I am now trying to drive the bytes from the video card (RS422 port) to the Arduino I/O in order to trigger my stopwatch.
I've got a GND and a T+ (or T-) with 3V3 signal from the video card (RS422).
It seems to suit well the Arduino digital I/O.
The goal is to plug the T+ to the pin 2 (or 3) of the Arduino Uno, and then to plug the GND to the GND of the Arduino. Then, once the message from the video card is sent, the stopwatch could be triggered using the following code :
const byte numPins = 8; // how many leds
int state; // used for HIGH or LOW
// pins to connect leds
byte pins[] = {5, 6, 7, 8, 9, 10, 11, 12};
const byte interruptPin = 3; // pin which would trigger the Arduino StopWatch from the RS422 of the video card
unsigned long t0Micro = 0; // Time recording
unsigned long CurrentMicro = 0; //Time recording
const long interval = 1000; // Time step for the increment of the leds in microsecond
unsigned long error = 3 ;
//int saveTime [60];
int l =0;
int k = 0;
int data =0;
int What =0;
int trigger =0;
void setup()
{
Serial.begin(38400); // RS422 video card
/* we setup all led pins as OUTPUT */
for(int i = 0; i < numPins; i++) {
pinMode(pins[i], OUTPUT);
digitalWrite(pins[i], LOW);
}
pinMode(13,OUTPUT); // Just to check if the code will run through
digitalWrite(13, LOW);
pinMode(interruptPin,INPUT_PULLUP);
attachInterrupt(digitalPinToInterrupt(interruptPin), blink, LOW);
}
void loop()
{
if(trigger=1)
{
digitalWrite(13, HIGH);
t0Micro = micros();
for (k = 1; k<600; k++) // 600 times 0.1 second = 1 minute running
{
for(int i = 0; i < numPins; i++) // All the led r turned off
{
digitalWrite(pins[i], LOW);
}
for (l = 1; l<101 ; l++)
{
CurrentMicro = micros();
//if (l==1 && k==0){Serial.println(CurrentMicro - t0Micro);}
error = CurrentMicro-t0Micro - (k-1)*100*interval-l*interval;
if (CurrentMicro-t0Micro >= (k-1)*100*interval+l*interval) // if the duration between two numbers is more than 1 millisecond
{
if (l==100 && k%10==0){Serial.println(error);}//saveTime[k/10] = error; // print the error between the starting time and now
//Serial.print(l);
String binNumber = String(l, BIN); // convert the number is binary
/* get the length of the string */
int binLength = binNumber.length();
for(int i = 0, x = 1; i < binLength; i++, x+=2) // turn the led ON and OFF according to the binary of the current number
{
if(binNumber[i] == '0') state = LOW;
if(binNumber[i] == '1') state = HIGH;
digitalWrite(pins[i] + binLength - x, state);
}
}
else { l--;}
}
}
}
trigger=0;
}
void blink()
{
trigger=1;
}
However, as soon as I teletransmit the code, the Arduino stopwatch start.
I have no idea where it would come from.
Thank you in advance for any help/feedback.
David
