Around here those time frames are considerably smaller. I'm lucky if things I did yesterday make sense tomorrow, or even late enough today. 
a7
3 Likes
LarryD, was I right on my answer to your question below?
-
We use Macros to help document our code, HIGH/LOW mean nothing.
Hence#define LEDon HIGHmakes more sense when we read our code.
.
digitalWrite(testLED, LEDon);is all we need to document our code. -
The following lines of code are already documented:
-
When the switch on D02 closes . . .
//make this TIMER 2 seconds
commonTIMER.setInterval(2000ul); //i.e. we are setting a TIMER object called commonTIMER to 2 seconds
//start this TIMER
commonTIMER.enableRestartTIMER(); //i.e. we now start the commonTIMER object
//next state
mState = STATE1; //i.e. we now set out mState (State Machine variabel) to STATE1 (which is actually equal to 1)
- Yes you are right
it simply is there to make the LED go to the opposite state.
On this topic (C++ Enumeration), I have not been exposed to this. Will need to take some time to read, absorb and put into practice.
- We always write our sketches so they are non blocking.
i.e. we avoid using delay( ) and avoid while( . . . ) as much as possible.
-
We are telling the heartbeat LED to toggle (flash) every 500ms.
Look at your LED, you should observe this happening. -
Let's say we update out sketch with new code and now the heartbeat LED stutters or flashes once per 3 seconds.
-
The LED can give us a rough indication things are working properly.
-
Stuttering or or not flashing at 1Hz means our new code has a problem.
-
Do you understand what we are doing is creating a C++ TIMER object ?
-
It has the name heartbeatTIMER, it is a millis based TIMER, its time-out is 500ms (1/2 sec), the TIMER is enabled and it auto-restarts.
The TIMER is now set to expire every 200ms
//========================
makeTIMER heartbeatTIMER =
{
//.TimerType, .Interval, .TimerFlag, .Restart, .SpeedAdjustPin
MILLIS, 200ul, ENABLED, YES, 0
};
- Excellent !
So, are you saying that instead of coding this:
if (mySwitch.lastState == CLOSED)
{digitalWrite(testLED, HIGH);
We should code it this way:
if (mySwitch.lastState == CLOSED)
{digitalWrite(testLED, LEDon);
because we earlier did this:
#define LEDon HIGH
- We can still carry on, I will be revisiting this later.
-
Yes
-
BTW always place { and } on lines by themselves and always format your sketch with <CTRL><T> or <CMD><T>.
I like the idea of a millis based sketch.
So, it appears that when we create an object called heartbeatTIMER, it has 5 parameters that you list as:
MILLIS, 500ul, ENABLED, YES, 0
Is that correct?
Meaning,
- it is MILLIS based
- The time period is 500 milliseconds
- The timer is ENABLED for now
- YES meaning it is to reset after timing out?
- 0 means ???
-
Every now and then we need to speed up our code so we don't have to wait for things to happen.
-
Let's say a LED was to toggle every hour.
There is no way I am going to stay and wait for an hour. (only at the doctors office) -
The 5th member can be added so a potentiometer can be used to tune/speedup a TIMER.
//========================
makeTIMER heartbeatTIMER =
{
//.TimerType, .Interval, .TimerFlag, .Restart, .SpeedAdjustPin
MILLIS, 500ul, ENABLED, YES, A4
};
- Above, a potentiometer connected to GPIO A4 can be turned to increase the speed that that TIMER runs at.
It's a debugging feature.
1 Like
Got it!
- How many TIMER objects are we making here ?
//========================
makeTIMER heartbeatTIMER =
{
//.TimerType, .Interval, .TimerFlag, .Restart, .SpeedAdjustPin
MILLIS, 500ul, ENABLED, YES, 0
};
//======================== (5ms * s_filter) i.e. 5ms * 10 = 50ms for checking a valid switch operation
makeTIMER switchesTIMER =
{
//.TimerType, .Interval, .TimerFlag, .Restart, .SpeedAdjustPin
MILLIS, 5ul, ENABLED, YES, 0
};
//========================
makeTIMER machineTIMER =
{
//.TimerType, .Interval, .TimerFlag, .Restart, .SpeedAdjustPin
MICROS, 1000ul, ENABLED, YES, 0
};
//========================
makeTIMER commonTIMER =
{
//.TimerType, .Interval, .TimerFlag, .Restart, .SpeedAdjustPin
MILLIS, 1000ul, DISABLED, NO, 0
};
1 Like
4 timers: heartbeatTIMER, switchesTIMER, machineTIMER and commonTIMER
-
Take a look at the loop( ) code in the sketch offered you in Post #17.
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You should see there are 3 TIMERs that are being examined.
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Every 500ms we toggle the heartbeat LED.
Every 5ms we check our switches.
Every 1ms we service our state machine. -
Once we service the State Machine, we start things all over again.
-
This all happens in ~28us, the time it takes loop( ) to execute.
- Yes !
i.e. 4 TIMER objects.
- Looking at page 3 in the flow chart and at the sketch offered in Post #17 correlate between them.
Is there anything that you would like explained ?
There is but I need to run an errand. Let's pick this up again later. Thank you so much for all you have shared thus far! I have already learned alot today!!
-
Correlate between the two images below and the code from Post #17.
-
let’s say we push the switch on GPIO D02.
The code that monitors the switch sees the switch is closed, it turns ON the testLED and initializes the commonTIMER object.
.
i.e. it sets the commonTIMER to 2000ms and it starts the TIMER.
.
We then make our State Machine go from the STARTUP state to STATE1 -
In STATE1, we check to see if the commonTIMER object has expired, if not, we just leave the State Machine.
.
If the commonTIMER object is expired, we disable the commonTIMER object, turn off the testLED and make our State Machine go back to the STARTUP state.
