NQC: Not Quite C (last updated 9/14/05 2:24pm) Each NQC program has a task main () The program is contained within curly braces { ….. } task main() { SetSensor(SENSOR_1, SENSOR_TOUCH); OnFwd(OUT_A); until(SENSOR_1 == 1); Off(OUT_A); }

task main() { SetSensor(SENSOR_1, SENSOR_TOUCH); OnFwd(OUT_A); until(SENSOR_1 == 1); Off(OUT_A); } Statements are separated by ; The language is case sensitive OnFwd(OUT_A) is different from onfwd(OUT_A)

task main() { SetSensor(SENSOR_1, SENSOR_TOUCH); OnFwd(OUT_A); until(SENSOR_1 == 1); Off(OUT_A); } SENSOR_1 refers to the sensor on sensor port 1 SetSensor defines SENSOR_1 to be a touch sensor OUT_A refers to the output port A OnFwd(OUT_A) turns on port A in forward direction OnFwd(OUT_A+OUT_B) turns on port A & port B in forward direction

The until statement until(condition) body ; Executes the body zero or more times until the condition is true. Assignment operator: x=5 assigns the value 5 to the variable x. Relational operator: x==5 has a value true if the value of x is 5 false if the value of x is not 5

until(SENSOR_1 == 1) ; sensor 1 is a touch sensor The output of a touch sensor is binary when the switch is open the output is 0 when the switch is closed the output is 1 When the sensor is open, what statement is executed? The null statement You don’t have to leave any spaces The ; indicates the end of this statement. When the sensor is open, the null statement is executed over and over again. It is like the program holds on this statement until the switch is closed.

Several forms of the until statement until(SENSOR_1 == 1) ; until(SENSOR_1 == 1) OnFwd(OUT_B); until(SENSOR_1 == 1) note: no ; here { On(OUT_A); On(OUT_B); } note: no ; here

Comments task main() { SetSensor(SENSOR_1, SENSOR_TOUCH); // Execution of the following statement turns // on output port A to full value. OnFwd(OUT_A); until(SENSOR_1 == 1); Off(OUT_A); } All characters following // until the end of a line are treated as comment.

What do the following statements do? Float(Out_B); Rev(Out_B); Toggle(Out_A + Out_B); OnFwd(Out_A); // turn on A in forward direction OnRev(Out_A); On(Out_A); Turns A on. If the last state was reverse, it will now be in reverse.

Controlling Timing OnFor(OUT_A, 100); Turns A on for 1 second Note OnFor(outputs, duration); Is different from OnFwd(outputs);

Controlling Power Output SetPower(OUT_A+OUT_B, 0); Sets the power to A & B to it’s lowest value SetPower(OUT_A+OUT_B, 7); Sets the power of A & B to it’s highest value SetPower(OUT_A+OUT_B, OUT_FULL); Same as the preceeding statement How many output levels are there?

Using #define You can name various motors and sensors #define LEFT_TREAD OUT_A note below On(LEFT_TREAD); Allows you to remember what is attached to different ports. Note: Statements which begin with # are directives for the preprocessor they do not have semicolons following them.