I discovered AS7 and VM about two months ago. I went from Arduino IDE straight to AS7/VM at the same time. After much futzing I am at the point where I have used the free version to set breakpoints in the code and run the simulator and debugger. 

I have a JTAGICE MKII connected to the ISP port and can read and program the fuses as well as load the bootloader onto an unprogrammed ATMEGA328P.

I am pretty confused about where any one of the above items end and where the next begins.

I have a simple traffic light VS7/VM solution. It uses a hardware interrupt Int0 on Pin3.

I can set breakpoints , see I/O pin states, and watch my target arduino LED tree hardware track right along with where the breakpoints are set in my sketch. Sweet. 

At one point I was able to use Int0 and increment a counter inside of the Interrupt Service Routing and see it change on the serial.print when I went back into the loop. 

I had the JTAGICE in SPI mode when it did not crash (above). Now I can not seem to get it to react like that, incrementing the counter in the interrupt service routine. Now when I push the interrupt button the serial monitor prints a "VM" and I have to recompile without debug and then recompile with debug to get the program to work in breakpoint mode. 

I would appreciate any insight into what is going on above.

Here is my test sketch. 



int isr_ctr =0;    //debug how many times the ISR runs
int stop = 2;
int yellow = 2;
int go = 7;

void setup() {       // put your setup code here, to run once:
     Serial.begin(9600);
     pinMode(8,OUTPUT);          //Red LED
     pinMode(9,OUTPUT);          //Yellow LED
     pinMode(10,OUTPUT);         //green LED
     pinMode (11,OUTPUT);        // OUTSIDE GREEN LED --BUTTON PUSHED
     
     // pinMode(5,INPUT_PULLUP);    //input red switch  flapping input
     // pinMode(6,INPUT );          //input red switch with 5k pullup
     digitalWrite(8,HIGH);   
     Serial.println ("traffic-- int_ctr INITIALIZING" );
     Serial.print ("Stop Variable is  ");
     Serial.println ( stop );
     digitalWrite(9,HIGH);
     Serial.print ("Yellow Variable is  ");
     Serial.println ( yellow );
     digitalWrite(10,HIGH);
     Serial.print ("Go Variable is  ");
     Serial.println ( go);
     digitalWrite (11, HIGH);
     attachInterrupt (0, changeTime,RISING); // FALLING EDGE, INT0-PIN3 (D2) isr= changeTime
delay( 1000);
}

void loop() {                              // put your main code here, to run repeatedly:
     
     golight(go);
     yieldlight(yellow);
     stoplight (stop);
}

void golight (int time) {
     digitalWrite(8,LOW);
     digitalWrite(9,LOW);
     digitalWrite(10,HIGH);
     Serial.println ("time - go  - ISR   ");
     Serial.print (time);
     Serial.print  ("   -- ");
     Serial.print (go);            // debug
     Serial.print  ("   --  ");
     Serial.println( isr_ctr);
     Serial.println("");
     delay(time * 500 );
     digitalWrite(11,LOW);
     go = 2;
}

void yieldlight (int time) {
     digitalWrite(8,LOW);
     digitalWrite(9,HIGH);
     digitalWrite(10,LOW);
     delay(time * 500 );
     }


void stoplight (int time) {
     digitalWrite(8,HIGH);
     digitalWrite(9,LOW);
     digitalWrite(10,LOW);
     delay(time * 500 );
}


void changeTime(){   // interrupt service routine - IO D3 momentary switch closed.
     isr_ctr++;       // debug count
     go = 5;
     digitalWrite(11,HIGH);

Good to know there are still kind folks like you Tim. 

So I guess I should be able to get the dWire interface to the arduino with the free version. I have not been very successful at this step. .....yet. 

I really want to see this do everything I see it doing on the internet.....like stepping into code and manupulating registers from AS7. 

Thanks.