Multiplexing SRAM,NOR Flash and NAND Flash ?

[antonius]

Posted on April 26, 2014 at 01:36

Guys,

How can I multiplex SRAM,NOR Flash and NAND Flash on PD7 ?

It's function as PD7 FSMC_NE1/FSMC_NCE2 on pin 88 for STM32F103VCT6,

is it configurable via software or I need to put a latch / multiplex chip for it ?

Any examples for it (schematic)? What's the common application for NAND flash ?

Can I run my code from NOR Flash ? I saw there's boot option

''System memory is selected as boot space'', page 48 STM32 reference, chapter 2.4 Boot Configuration...

Thanks

#fsmc

[Tesla DeLorean]

Posted on April 27, 2014 at 05:07

You would combine the Chip Select, with a high order address bit(s) and basic logic gates.

But seriously, why are you persisting with this part selection, surely there are better part choices?

[Tesla DeLorean]

Posted on April 27, 2014 at 05:10

so NOR flash is for code, copy to SRAM if I want to run it, then NAND flash is similar with SDcard as a storage....please correct me if I'm wrong, thanks

No, 16-bit NOR you could run-in-place, with NAND, Serial DataFlash or SDCard you'd need to copy to SRAM.

[antonius]

Posted on April 27, 2014 at 05:56

so I can only use either SRAM or NOR flash ?

I read :from AN2784 page 29, or for easier interface I'll use STM32F103ZET6 ?

[jpeacock2399]

Posted on April 28, 2014 at 15:45

Although you can execute code from memories on the FSMC bus the performance is terrible.  There's no cache, no prefetch, only 16 bit access, and external SRAM or NOR is much slower than the internal memory.  FSMC works much better as bulk data storage or as a parallel interface to a peripheral, like an LCD controller.

  Jack Peacock

[antonius]

Posted on April 28, 2014 at 16:00

I see,

so I will use NOR flash, and NAND flash for storage only, similar with SDcard but in the form of chip...

thanks