Memory usage difference between MPLAB and CCS

Arakel · Joined: 06 Aug 2016 Posts: 107 Location: Moscow

Good day to everyone and happy Spring!

I have a question about the memory usage accuracy of MPLABX and CCS. On CCS I get very high usage, while on MPLABX I get low RAM and ROM memory. Which one is accurate?

I am using MPLABX 3.50 with the CCS compiler plugin. I got similar results on a few projects.

[img]
https://www.dropbox.com/s/ov678uws005ye1j/MPLABX-1.png?dl=0
[/img]

[img]
https://www.dropbox.com/s/7y0fp79pfuckj40/CCS1.png?dl=0
[/img]
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Yo! I love learning and technology! I just do not have experience so do not be angry if I ask a stupid question about a detail! From so much to remember sometimes I forget the details in order to remember the big problems!

PCM programmer · Joined: 06 Sep 2003 Posts: 21708

What does the .LST file show ? The usage will be listed at the top of the file.

Ttelmah · Joined: 11 Mar 2010 Posts: 19520

It almost sounds as if the chip selection is not set right somewhere.

Arakel · Joined: 06 Aug 2016 Posts: 107 Location: Moscow

I put a random project, so I hit the ROM correctly.

MPLAB .lst file

[img]https://www.dropbox.com/s/03fubv336vtol8d/MPLAB-lst-1.png?dl=0[/img]

CCS .lst file

[img]https://www.dropbox.com/s/fhkg31i004oc8aj/CCS-lst.png?dl=0[/img]

MPLAB IDE

[img]https://www.dropbox.com/s/vol67roors46b1b/MPLAB-memory-usage.png?dl=0[/img]

CCS IDE

[/img]https://www.dropbox.com/s/2tmbz9izwb1bzpi/CCS-memory-usage.png?dl=0[img]
_________________
Yo! I love learning and technology! I just do not have experience so do not be angry if I ask a stupid question about a detail! From so much to remember sometimes I forget the details in order to remember the big problems!

Ttelmah · Joined: 11 Mar 2010 Posts: 19520

Both are using 33% ROM.

You have to set the option in MPLAB, to 'import symbols after compilation', otherwise it doesn't know what RAM is being used. This is why it is displaying a silly value (think about it, your float array is 20% of the available RAM straight away, yet MPLAB is showing 0%....

Same will apply to ROM for any project with significant constants stored. Depending on the chip, some of these aren't included in the code size unless the symbol table is loaded.

Arakel · Joined: 06 Aug 2016 Posts: 107 Location: Moscow

Ok, thanks, I did not know I have to check the .lst file to know the memory usage. I will see how set up the table.
_________________
Yo! I love learning and technology! I just do not have experience so do not be angry if I ask a stupid question about a detail! From so much to remember sometimes I forget the details in order to remember the big problems!

Arakel · Joined: 06 Aug 2016 Posts: 107 Location: Moscow

I clicked "enable" near the "Memory usage" but it did not work. Perhaps something else is wrong?
_________________
Yo! I love learning and technology! I just do not have experience so do not be angry if I ask a stupid question about a detail! From so much to remember sometimes I forget the details in order to remember the big problems!