I've been loosly following this thread.
as you guys know, I ran codec2 on the STM32F7 about 2 years ago, with
about 2x performance at same clock as the STM32F4 without using the TCM.
maybe it was 2.4x . anyway.I didnt do any mallocing , plenty of memory
available,
however, If the new codec code needs it for compatibility or memory
consider using the HEAP4.c memory allocating strategy in FREETOS
I've used freertos extensively the last 2 years, I use HEAP4, though
there are HEAP1,2,3,4,5 to take your pick from
One of the things I do with freertos and the F7 is run lots of web
services, which means lots of setting up and tearign down, no problem at
all with HEAP4.
just an idea.....
you dont need to use Freertos to use HEAP4.c, just have a look at the
code, just needs a block to work with.....
Glen
On 10/06/2018 10:30 PM, Steve wrote:
All those malloc/free really make me nervous in a non-MMU allocation
environment.
In my own testing, I have found that large automatic arrays (at the
top of the function), and malloc arrays (at the top of a function or
initialization section) create problems.
My solution is the old tactic of putting everything in the BSS. This
is memory that really does get allocated (not some virtual maybe
allocation) and it gets set to zero for free when you turn the power
on. On top of that, the heap and stack don't crash into it.
For example I was getting a popping sound on my sm1000 project in the
receive audio. So I tried changing the automatic variable to a
malloc/free and the popping got worse. I then changed it to BSS and
the popping was gone.
This, even though the memory is set to zero in a for/next loop. I
don't understand the popping unless the firmware interrupts are
interfering with the function execution time.
The newer modems are using two codec frames (four for 700D), which
mean they are rather large allocations compared to 1600 mode, so maybe
the new lengths and the interrupt timing are not optimized.
The completely undesirable part of my method, is it can't be aligned
back into the master code. That code is designed around malloc/free.
malloc/free are hugely black magic in a VM OS. Maybe too simplistic in
OS/MMU free boards with 1 kHz interrupts.
Maybe we need some critical/non-critical markers around sections of
code. Shut the interrupts off, do your memory allocation and
initialization, then turn the interrupts back on.
Just thinking...
------------------------------------------------------------------------------
Check out the vibrant tech community on one of the world's most
engaging tech sites, Slashdot.org! http://sdm.link/slashdot
_______________________________________________
Freetel-codec2 mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/freetel-codec2
------------------------------------------------------------------------------
Check out the vibrant tech community on one of the world's most
engaging tech sites, Slashdot.org! http://sdm.link/slashdot
_______________________________________________
Freetel-codec2 mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/freetel-codec2
