Mega 2560 no voltage output

No output from Arduino Mega 2560. Running Windows 10, Arduino 1.8.10, the following sketch:

#define MEGA_VIXEN
//#define UNO_VIXEN

#ifdef MEGA_VIXEN
#define MAX_CHANNELS 16
int channels[MAX_CHANNELS] = {2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 17, 18};
#endif

#ifdef UNO_VIXEN
#define MAX_CHANNELS 18
int channels[MAX_CHANNELS] = {2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, A0, A1, A2, A3, A4, A5};
#endif

int incomingByte[MAX_CHANNELS];

void setup()
{
int i;

Serial.begin(9600); // set up Serial at 9600 bps

for ( i = 0; i < MAX_CHANNELS; i ++ ) pinMode(channels*, OUTPUT);*
}
void loop()
{

  • int i;*
  • if (Serial.available() >= MAX_CHANNELS)*
  • {*
    for (i = 0; i < MAX_CHANNELS; i ++) incomingByte = Serial.read();
    * }*
    for (i = 0; i < MAX_CHANNELS; i ++ ) analogWrite(channels_, incomingByte*);
    }*

    My board powers up (ON LED lights up), L LED flashes on connect, sketch compiles and up loads. RX LED on continually, L LED flashes when I try to run a Vixen 3 sequence through USB to Arduino. No measurable voltage out from any pin 1-13, and obviously no action on the Sainsmart 8 relays attached.
    Last year I just downloaded the code, and the sketch, and it worked. No idea what changes may have been made to the computer in the interim.
    *I keep thinking I’m going to find a legend to tell me if these LED’s do this and those do that, what the problem is. *_

Now what could possibly be wrong in these 2 lines of code:

[i]for (i = 0; i < MAX_CHANNELS; i ++)      incomingByte[i] = Serial.read();[/i][/i]
[i][/i][i][i]for (i = 0; i < MAX_CHANNELS; i ++ )    analogWrite(channels[i], incomingByte[i]);[/i][/i][/i][/i]
[i][i][i][i][/i][/i][/i][/i]
[i][i][i][i]

empac99:
when I try to run a Vixen 3 sequence through USB to Arduino.

It would help if you were to tell us what aVixen 3 sequence is, what is sending it and give us an example of it.

It would also be a useful debugging aid if you have a Serial.print() statement to show what values the Mega actually receives.

Maybe have a look at the examples in Serial Input Basics - simple reliable ways to receive data.

...R

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