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Grogster

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Joined: 31/12/2012
Location: New Zealand
Posts: 9308

Posted: 04:20pm 16 Mar 2014

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I am having issues restarting the tick timers.

In a routine, I stop all the tick timers, which just add to a counter for a screen-saver, and draw the clock and pulse and external WDT.

Stopping them is fine, but then they won't restart for me.

So, at the very top of the code, I start the timers thus:

settick 250,DAT,1:SEttick 500,WDT,2:settick 1000,SST,3

...then in the processing routine, I turn them all off to stop them interferring with the processing:

settick 0,0,1:SEttick 0,0,2:settick 0,0,3

This is all fine, but when I exit from the routine back the main menu when the timers need to be restarted, just before I go to the main menu, I try to re-enable the tick timers with:

settick 250,DAT,1:SEttick 500,WDT,2:settick 1000,SST,3

...but they don't start - they stay off.

Any ideas what I am doing wrong?

Smoke makes things work. When the smoke gets out, it stops!

Grogster

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Joined: 31/12/2012
Location: New Zealand
Posts: 9308

Posted: 04:35pm 16 Mar 2014

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Well, I wrote a basic testing code thus:

settick 250,DAT,1:SEttick 500,WDT,2:settick 1000,SST,3

cls

print "Timers running..."
pause 2000
print "Stopping timers..."
settick 0,0,1:settick 0,0,2:settick 0,0,3
print "Timers stopped."
pause 2000
print "Restarting timers..."
settick 250,DAT,1:SEttick 500,WDT,2:settick 1000,SST,3

DO:LOOP

end

DAT:
A=A+1
print @(50,100); A
ireturn

WDT:
B=B+1
print @(50,115); B
ireturn

SST:
C=C+1
print @(50,130); C
ireturn

...and they stop and start fine, so there must be some kind of bug in my code somewhere - perhaps I am stopping them somewhere else.

Hunt, hunt, hunt.........

Smoke makes things work. When the smoke gets out, it stops!

Grogster

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Location: New Zealand
Posts: 9308

Posted: 05:41pm 16 Mar 2014

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I can't find any other place where I might have stopped the timers.
I do stop them in the screensaver, but they are re-enabled when you press a key, and those ones DO re-enable.

Smoke makes things work. When the smoke gets out, it stops!

Geoffg

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Joined: 06/06/2011
Location: Australia
Posts: 3196

Posted: 07:44pm 16 Mar 2014

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I have just had a look through the source and I cannot see anything that would stop you from re enabling them.

Geoff

Geoff Graham - http://geoffg.net

Grogster

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Location: New Zealand
Posts: 9308

Posted: 07:48pm 16 Mar 2014

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Yeah, I don't get it - I am about to print out all the code, then lay it all out on the table and examine it line by line - there must be a bug in there somewhere.

I thought that perhaps MMBasic did not like having the tick timers stopped and started more then once or twice, so I wrote this test code:

settick 250,DAT,1:SEttick 500,WDT,2:settick 1000,SST,3

mode 4:cls

print @(20,20)"Timers running..."
pause 3500
print @(20,40)"Stopping timers..."
settick 0,0,1:settick 0,0,2:settick 0,0,3
print @(20,60)"Timers stopped. "
pause 3500:gosub clines
print @(20,20)"Restarting timers...(1)"
settick 250,DAT,1:SEttick 500,WDT,2:settick 1000,SST,3
pause 3500:gosub clines
print @(20,40)"Stopping timers...(1) "
settick 0,0,1:settick 0,0,2:settick 0,0,3
print @(20,60)"Timers stopped.(1) "
pause 3500:gosub clines
print @(20,20)"Restarting timers...(2)"
settick 250,DAT,1:SEttick 500,WDT,2:settick 1000,SST,3
pause 3500:gosub clines
print @(20,40)"Stopping timers...(2) "
settick 0,0,1:settick 0,0,2:settick 0,0,3
print @(20,60)"Timers stopped.(2) "
pause 3500:gosub clines
print @(20,20)"Restarting timers...(3)"
settick 250,DAT,1:SEttick 500,WDT,2:settick 1000,SST,3
pause 3500
print @(20,60)"Test finished. "

DO:LOOP

clines:
print @(20,20)" "
print @(20,40)" "
print @(20,60)" "
return

end

DAT:
A=A+1
print @(50,120); A
ireturn

WDT:
B=B+1
print @(50,140); B
ireturn

SST:
C=C+1
print @(50,160); C
ireturn

But they(the timers) all stopped and started fine to the end of the test code.

Smoke makes things work. When the smoke gets out, it stops!

Grogster

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Location: New Zealand
Posts: 9308

Posted: 08:34pm 16 Mar 2014

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FIXED IT!

I am still learning interrupts, and made the same mistake twice.

I was calling the processing routine from within the interrupt(thinking I was being clever), and thus that interrupt, once called, never got returned, and so the tick timers could never be set again.

The fix was easy - set a flag within the interrupt, and check that OUTSIDE of the interrupt, once it had been returned. Once I did that, everything is working fine.

Perhaps an entry in the MMBasic Bible: "Thou shalt ALWAYS return interrupts."

Edited by Grogster 2014-03-18

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Lou

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Joined: 01/02/2014
Location: United States
Posts: 229

Posted: 07:47am 17 Mar 2014

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"Thou shalt ALWAYS return interrupts."

Grog,

I don't have enough fingers and toes (and maybe hairs left) to count the times I've done that. I usually find it after the program crashes in a big WTF.

Usually good for a couple of chuckles...

Lou

Microcontrollers - the other white meat

MicroBlocks

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Joined: 12/05/2012
Location: Thailand
Posts: 2209

Posted: 08:31am 17 Mar 2014

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Grog,

I would suggest using defined subroutines for your interrupt handlers (and other subroutines).
You would then not need a label and a specific ireturn/return.
Also the change of 'falling through' from another label is then impossibe.
Your program will be more robust.
Using it is simple (Ain't everything! :) )

isntead of using this:
[code]
WDT:
B=B+1
print @(50,140); B
ireturn
[/code]
you use this:
[code]
SUB WDT
B=B+1
print @(50,140); B
END SUB
[/code]

Have fun!

Microblocks. Build with logic.

Grogster

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Joined: 31/12/2012
Location: New Zealand
Posts: 9308

Posted: 11:26am 17 Mar 2014

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@ Lou - Yeah, all fun and games until something goes wrong, and you spend hours scratching your head trying to find the bug! Some bugs can hide themselves VERY well.

@ TZA - Yeah, that is an idea. I thought that an interrupt HAS to return with an IRETURN. However, reading the manual a bit more, I found that with the tick timers, you can call a sub as an interrupt, and just have the END SUB, as you show in your example. Sounds like a good idea - will check it out.

Smoke makes things work. When the smoke gets out, it stops!

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