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memory addressing

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Jane11

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In my Linux embeded device I have 4 SDRAM modules.( Each module is of
16 bit data bus and 13 bit address bus )
I need to find out how they are addressed

if it is like this :

1st address in module 1
2nd address in module 1
3rd address in module 1
4th address in module 1
5th address in module 1
6th address in module 1
7th address in module 1
8th address in module 1
...
...
the last but one address in module 4
the last address in module 4


or
1st address in module 1
2nd address in module 2
3rd address in module 3
4th address in module 4
5th address in module 1
6th address in module 2
7th address in module 3
8th address in module 4
..
..
the last but one address in module 3
the last address in module 4

Is it possible?
( Via JTAG I can "talk" to CPU directly and write to an address, if it helps)
Thanks
 
it would most likely be case A

1st address in module 1
2nd address in module 1
3rd address in module 1
4th address in module 1
5th address in module 1
6th address in module 1
7th address in module 1
8th address in module 1
...
...
the last but one address in module 4
the last address in module 4
 
Thank you for the reply.

Yes, I think so too.But there are 2 more bits ( marked BA0 and BA1) marked as bank select address( each module consists 4 internal banks).
Besides there is CS( chip select) bit.

Do you think that these two(= BA0,BA1) or even those three( =BA0,BA1 and CS) bits are 14 and 15 and 16 bits that is they are the MOST significant bits( the first bits in the address) or the LEAST significant( the last 3 bits?)
Thanks for the reply
 
OK, my take it really depends. If the device supports interleaving, then it's likely that odd addresses come from one bank and even from another. Memory modules must be the same size and usually they are labeled as such. e.f A0, B0 for A and B on bank 1.

I SUPPOSE that 4 banks would be useful for a quad core processor to boost performance even more.

Bank select would likely be the Most significant bits.

My take.
 
If it's a 16 bit processor then it's anyone's guess. If it's a 32 bit processor then it makes sense to read from two modules at the same time. If 64 bit then all four modules.

Mike.
 
Thank you for the replies.
@KeepItSimpleStupid: No, I do not think it is NOT quad core processor.
@Mike, yes, it is a 32 bit processor, but SDRAM is a 16 bit only.Does it mean the CPU reads double words at a time?HOw can I check it?
How can I identify which word is from which module?
Thanks
 
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