This discussion has been locked.
You can no longer post new replies to this discussion. If you have a question you can start a new discussion

external memory

Hi,
I work on ST10F168 and i use external ram by EBC in 16 bits demux mode with keil V2.38
There are 4 Chip Select available for ram : CS1,CS2,CS3,CS4
and 23 adress bits : A1->A23
So, there are (2^23 * 4) bytes accessible <=> 32Mo
I would to know if i am right and if i can declare an external memory map of 32 Mo !
Thanks for any suggestions !

Regards,
Jim

Parents
  • Not sure what you mean there, but I'll try to answer anyway. The size of the address space is 16M bytes. That means that you can't address more than that directly (without bank switching). You can address slightly less than 16M bytes via the external bus. You can address more with bank switching, as discussed earlier.
    16M x 8 bits is 16M bytes. 16M x 16 bits is 32M bytes.

    - mike

Reply
  • Not sure what you mean there, but I'll try to answer anyway. The size of the address space is 16M bytes. That means that you can't address more than that directly (without bank switching). You can address slightly less than 16M bytes via the external bus. You can address more with bank switching, as discussed earlier.
    16M x 8 bits is 16M bytes. 16M x 16 bits is 32M bytes.

    - mike

Children