How are you doing on RAM space?
On Sat, Oct 24, 2015 at 9:23 PM, David Rowe <[email protected]> wrote: > Hi Steve, > > There's plenty of flash left for the cohpsk modem, we already have the > entire codec and fdmdv modem fitting in around half the flash. > > No need to load any program code - it all runs out of flash. > > It's important to test and characterise, hence the porting steps I > suggested on 24 Sep. > > - David > > On 25/10/15 12:00, Steve wrote: >> On Sat, Oct 24, 2015 at 7:55 PM, Stuart Longland >> <[email protected]> wrote: >>> On 25/10/15 10:49, Steve wrote: >>>> Added to the language in C99 if I remember right... No problem in GCC. >>> >>> Ahh, figured it was a newer feature. I sometimes have to deal with K&R C. >>> >> >> The difference of course, is that Variable Length Arrays (VLA) are >> allocated on the stack, rather than the heap, as in the old days. >> Stack space may need to be weighed if you are creating some huge >> arrays. >> >> I'm kind of old fashioned in my C programming. I don't really like >> HEAP or STACK, and tend to favor BSS. The nice thing about BSS >> storage, is it is auto-initialized to zero. This can save a lot of >> code at the initialization step, with loops allocating zero's to >> arrays. Then to, there is no danger of the BSS crashing into the STACK >> or the HEAP, while the later crash all the time out in the wild. >> >> Somewhere along the line someone declared BSS evil (globals are evil) >> and usage waned. Course now in OOP languages it is like making the >> sign of the cross inside a Mosque... >> >> Having looked at the cohpsk modem, it is going to need a ton of >> memory, then too, you'll need to save room for the vocoder. >> >> I think the best bet may be to load the two modems from flash >> separately depending on which modem the user wants. Running both >> probably will run out of memory. The cohpsk modem, for example doesn't >> need all the pilot code and allocated space, but does have some rather >> large filter tables. >> >> Just some thinking out loud... >> >> ------------------------------------------------------------------------------ >> _______________________________________________ >> Freetel-codec2 mailing list >> [email protected] >> https://lists.sourceforge.net/lists/listinfo/freetel-codec2 >> > > ------------------------------------------------------------------------------ > _______________________________________________ > Freetel-codec2 mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/freetel-codec2 ------------------------------------------------------------------------------ _______________________________________________ Freetel-codec2 mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/freetel-codec2
