How to install GCC 4.7.1

[MikeB]

Just tried this myself. Saves nearly 480 bytes, but doesn't work! I'll have a little look.

Mike.

[MikeB]

The 4.8.0 compiler seems to be compiling the function evalChkSum() into a single jump to itself!
Very odd, and clearly stops the program from running.
I've tried a few variations on the code, and also put it into another source file, still the same!

Mike.

[ReSt]

I still have a full copy of my 4.8.0 directory available. So if there will be a simple fix for it, I can try it.
(Simple means, replace file x with file y from z)

Reinhard

[MikeB]

4.8.0 seems to dislike accessing past the end of an array. In pers.cpp, replace evalChkSum() with this version.

Code: Select all

uint16_t evalChkSum()
{
  uint16_t sum=0;
	uint16_t *p ;
	p = ( uint16_t *)g_eeGeneral.calibMid ;
  for (int i=0; i<12;i++)
	{
    sum += *p++ ;
	}
  return sum;
}

This seems to fix the problem.

Mike.

[ReSt]

Thanks,
will give it a try.


Reinhard

[ReSt]

Modified the pers.cpp file accordingly.
It now compiles, but the resulting hex files are greater, around 100 bytes, than the files from 4.7.1

My 4.8.0 is obviously not the very best one. IIRR I had to use some files from the 4.7.2 version to get it going.
Do you have a link to an actual 4.8.0 version for windows, that simply can be installed ?


Reinhard

[MikeB]

No, I did the same as before, downloaded a ZIP file, then copied files over the top of the existing compiler.
This is where I got the download from:

http://kent.dl.sourceforge.net/project/ ... ingw32.zip

Went to my WINAVR-20100110 directory and created a 4.8.0 sub-directory.
Copied the five sub-directories (avr, bin, lib, libexec and share) from the zip file to it.
Copied the sub directory WinAVR-20100110\4.8.0\libexec\gcc\avr\4.8.0 to WinAVR-20100110\libexec\gcc\avr\4.8.0
Copied WinAVR-20100110\4.8.0\avr to C:\WinAVR-20100110\avr
Copied the contents of \WinAVR-20100110\4.8.0\bin (except avr-size.exe) to C:\WinAVR-20100110\bin

I have previous compiler versions in 4.7.2, 4.7.0 and 4.3.3 sub-directories.
To revert to 4.7.2, copy WinAVR-20100110\4.7.2\avr to C:\WinAVR-20100110\avr and the contents of \WinAVR-20100110\4.7.2\bin (except avr-size.exe) to C:\WinAVR-20100110\bin

Mike.

[ReSt]

Mike, thanks for the link.

I downloaded the zip and unpacked it into a folder.
From there I copied all subfolders, avr, bin, lib........(except the avr-size.exe) into an existing 4.7.2 setup, replacing all existing files.

This does work and my newly compiled FrSky.hex (with heli and templates)/ NMEA.hex were 250 / 194 bytes smaller than with 4.7.2.
And the flashed radio seems to work normally.

Reinhard

[MikeB]

I've been using AVR-GCC 4.8.0 for nearly 2 years so I thought I'd try the latest release, which is 4.9.2.
I did the update as described above.
Unfortunately, the compiled code is some 3.7% larger than with 4.8.0 (66224 insterad of 63874).
I've reverted to 4.8.0!

Mike.