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Grogster

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

Posted: 02:44pm 19 Jun 2013

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Hi all.

I was looking at possibly resetting the MM in the code.
I can't see any command for that in the manual.

Perhaps it can be done by poking a memory location?

Other then that, I can use an I/O pin, pulled high with an external 10k or so, connected back to ~MCLR and pulse it low in the code to force a reset, but is there any way to do that in code with a simple command?

Does not matter if not - I will just use the I/O pin method.

I plan to have a "RESET" push button on the system, but I am not willing to put this directly on ~MCLR, as if the SD card is writing especially, resetting during a card write is not a good thing.

So, I was going to have the "RESET" button connected to a normal I/O line and setup an interrupt for that line, so that if it is ever pressed, it will loop to a short bit of code which just closes any open files, then performs a soft-reset to restart the system.

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

MicroBlocks

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

Posted: 04:37pm 19 Jun 2013

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Often a user reset button is connected to a non maskable interrupt to do the reset under software control.
A tiny button hidden behind a small hole is the one that is connected to the reset line. Having both is good otherwise people just recycle power.
You would need a small battery or a (super)cap to provide enough power and an input line to detect the power loss to safe important info when that happens.

Microblocks. Build with logic.

Juri74

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Joined: 06/02/2012
Location: Italy
Posts: 162

Posted: 11:42pm 19 Jun 2013

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Hello grogster,
for a fast software reset try POKE 1,1,1

Grogster

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Posts: 9308

Posted: 11:54pm 19 Jun 2013

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Poke 1,1,1 crashes the system, it does not reboot it...

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

MicroBlocks

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

Posted: 12:37am 20 Jun 2013

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If you setup an interrupt on an i/o port then you could use this:
[code]
handleInterrupt:
'close files here if necessary
CLS
Print 'Restarting.....'
RUN "YOURPROGRAM.BAS"
IRETURN
[/code]
This will reboot the BASIC program.
Edited by TZAdvantage 2013-06-21

Microblocks. Build with logic.

Juri74

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Joined: 06/02/2012
Location: Italy
Posts: 162

Posted: 05:34am 21 Jun 2013

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i think i found a bug... surely pokeing here and there in memory will end in a crash, ofcourse!
poke 1,1,1 is a proof of it.. but shouldn't be safe peeking memory? even theese critical memory locations?

try

PRINT PEEK(1,1)

Juri

Geoffg

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Joined: 06/06/2011
Location: Australia
Posts: 3194

Posted: 12:27pm 21 Jun 2013

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No, that is referring to an illegal address and the hardware in the PIC32 catches it and forces an exception (this is out of the control of MMBasic).

Theoretically it is possible for MMBasic to validate the address before it attempts to use it but there are so many valid/invalid addresses in the PIC32's memory map that it would be too complex and error prone.

Geoff

Geoff Graham - http://geoffg.net

Dylan
Regular Member

Joined: 17/06/2013
Location: Netherlands
Posts: 81

Posted: 01:25pm 21 Jun 2013

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I think I tried PEEK(1, 1) too - unless I was trying to peek 1fc/bfc the other month. Slow learner.

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