Again about SDRAM plain memory

Go To Last Post
3 posts / 0 new
Author
Message
#1
  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

I guys, so as I can read from old posts, the Xplain's SDRAM can't be used for a size over 64K? This is true?

There are news about this problem? is it possible now to use it? As I can read it was a problem of AVR-GCC right?

I'm trying the ATMEL appnote AVR1312 that fill some SDRAM locations with 0xff and then read them, but also changing the ASPACE meory into 8mB, Im not able to use more than 49170!!! At so strange number! :)
I write 49170 locations with the 0xff number and than I read them. if they are all at 0xFF I switch on a led. But... with 49170 the led become on, with higer numbers no.

Ok hoping one day to have 8MB avaible for to play, I wait some answer.
Thanks
Davide

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

If you are asking whether pointers in GCC are 16 bit (and therefore limited to addressing 64K bytes of RAM or 64K words of code flash) then, yes, you are right. But nothing stops you taking control of the RAMPD, RAMPX, RAMPY and RAMPZ yourself - though this may mean resort to Asm code. Set RAMPD then use LDS/STS, Set RAMPX/Y/Z then use LD/ST with X, Y or Z

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

ok thank you very much for your answer.
I'll try to use it in other way.
regards
Davide