Timer Problem

Hi,

I ran into trouble on timer issue. My project includes a 4 pin Rotary Switch to select 4 different time inputs, 30, 60, 90 seconds, and an hour. However, I ran into trouble having the timer to stop the motion at 30 seconds through out all the pins. I know that arduino can run for 50 days till it overflow, but when I compile the program, it gave me overflow warning for anything bigger than 30 seconds. Please let me know if there is anyway to fix this issue. I use Arduino Uno.

SBSv5.9_Question.ino (1.1 KB)

All time variables should be unsigned long

long startTime;

long stopTime;

int k;

as that is what millis() returns.

These need to fixed

if (digitalRead(DOOR) == HIGH) {

if (HIGH == digitalRead(TIME1_PIN)) {

k= RUNTIME1;}

else if (HIGH == digitalRead(TIME2_PIN)) {

k= RUNTIME2;}

else if (HIGH == digitalRead(TIME3_PIN))

HIGH == is not how a comparison starts. The first if() is correct syntax.

I know that arduino can run for 50 days till it overflow,

It can run for ever without the millis() rollover to zero being a problem as long as it is programmed correctly.

when I compile the program, it gave me overflow warning for anything bigger than 30 seconds

Sorry, but I have no idea what you mean by this.

I get no errors reported when I compile the program, but that does not mean that the program will work as you want.

HIGH == is not how a comparison starts. The first if() is correct syntax.

There is nothing wrong with doing the comparison with HIGH == first. In fact it is a way of avoiding the use of a single equals sign instead of 2 as intended because the compiler will report an error if only 1 is used, but it always looks odd to me.

when I compile the program, it gave me overflow warning for anything bigger than 30 seconds

Sorry I didn’t explain it well. It gave me this warning:

C:\Documents and Settings\BAX\Desktop\SBS_5.9.2\SBS_5.9.2.ino:62:8: warning: overflow in implicit constant conversion [-Woverflow]

k= RUNTIME3;}

^
So the problem is, when I turn on the punching machine, it stop the motion at 30 seconds no matter if I put 40, 60, 100000 seconds at any RUNTIME_PIN

SBS_5.9.2.ino (2.94 KB)

All time variables should be unsigned long as that is what millis() returns.

long startTime;
long stopTime;
int k; << int can’t hold 32 bits!

#define RUNTIME1 30000 << fits in int

#define RUNTIME2 60000 << fits in int - limit is 65535, allows 2^16-1 max

#define RUNTIME3 90000 << does not fit in int, use 90000UL, allows 2^32-1 max

#define RUNTIME4 3600000 //forever << does not fit in int, use 3600000UL, allows 2^32-1 max