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OA47

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Joined: 11/04/2012
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Posted: 07:22pm 28 Jan 2013

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I have been testing some code that I wrote that operates outputs at preset times. The code ran happily for about 5 days operating outputs until midnight that night when the code had to do some housekeeping (day of week etc)it crashed with the Error "Too many nested GOSUB" I have looked through the MMbasic Language Manual (V4) in particular the "Implementation Characteristics" area but cannot see a limit on the nesting of GOSUB's. Is there a limit and if so how would you check the number that the program has nested?

TassyJim

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Joined: 07/08/2011
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Posted: 09:50pm 28 Jan 2013

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The topic came up for discussion about 12 months ago.
http://www.thebackshed.com/forum/forum_posts.asp?TID=4469&PN =31

MM Basic has come a long way since then but I think the limits are still the same.

Jim

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MMedit MMBasic Help

OA47

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Posted: 10:07pm 28 Jan 2013

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Thanks TassyJim,
In that discussion Geoff has stated that the limit is 250. This number seems to be ample but I will have to check back thru my code and set a counter to see where I am coming unstuck.

djuqa

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Joined: 23/11/2011
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Posted: 11:00pm 28 Jan 2013

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I would be totally revisiting the code
5 Nested GOSUB would be a nightmare to debug
More than 250 Bloody Heck!

VK4MU MicroController Units

OA47

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Joined: 11/04/2012
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Posted: 11:15pm 28 Jan 2013

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Djuqa, The program has been trimmed to around 1100 lines of code, I have had to do this because I was running out of memory. If I have to do a major re-write I may have to put it on the back burner.

BTW
Even though there is no women around to hear him, she would know that he is still wrong.

MicroBlocks

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Joined: 12/05/2012
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Posted: 12:07am 29 Jan 2013

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250 is a lot. I suspect that there is a subroutine where it will call itself.
That can get the count up real quick.

Microblocks. Build with logic.

Geoffg

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Posted: 10:09pm 29 Jan 2013

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In an effort to save a little memory later versions have reduced the maximum number of nested GOSUBs to 100. Still a lot.

Geoff Graham - http://geoffg.net

OA47

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Posted: 11:05pm 29 Jan 2013

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Thanks for the update Geoff. As I havn't got enough memory for colour which version was wound down to 100 nested GOSUB's ?

Geoffg

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Posted: 11:35pm 29 Jan 2013

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Graeme Meager said Thanks for the update Geoff. As I havn't got enough memory for colour which version was wound down to 100 nested GOSUB's ?

Not sure without a lot of digging, probably 4.0. You can test it easily enough on the version that you are using.

GOSUB TST

TST:
A = A + 1
PRINT A
GOSUB TST

Geoff Graham - http://geoffg.net

OA47

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Posted: 04:06pm 02 Feb 2013

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Checked previous versions, Versions 3.XX have 250 nested GOSUB limit and Version 4.0X have 100 limit.

graynomad

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Joined: 21/07/2010
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Posted: 01:43pm 03 Feb 2013

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Even 100 is a limit you should never get remotely close to...unless of course you are doing some recursion.

Rob Gray, AKA the Graynomad, www.robgray.com

panky

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Joined: 02/10/2012
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Posted: 10:20pm 05 Feb 2013

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I agree Rob, I'm not a programmer but nesting GOSUBs in some form of loop that would get up to 100, particularly recursion and with the practical limits of the MM seems like a recipe for debugging hell and a future nightmare in the making.

Graeme, as an (not overly smart) observer, seems to me you might need to re-think your program structure. Not trying to teach you how to suck eggs, just a suggestion from my own experience,

Regards, Doug.

... almost all of the Maximites, the MicromMites, the MM Extremes, the ArmMites, the PicoMite and loving it!

JohnS
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Joined: 18/11/2011
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Posted: 12:42am 06 Feb 2013

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For cute things like Sierpinski curves and various other mathematical curios you might use a lot of recursion but otherwise I'm with you that it's unlikely to be needed.

Cmon Microchip let's have more RAM or an external memory bus...

John

graynomad

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Posted: 01:04am 06 Feb 2013

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Yeah I've used recursion many times, easy enough but you can get into trouble.

Rob Gray, AKA the Graynomad, www.robgray.com

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