Hi everyone,

I have been measuring the time the at45db flash memory chip takes to perform
every single operation. I need this to calculate the power consumption for
the chip. I have been using the BlockStorage component and I have measured
single operations time to complete within the At45dbP.nc component.

My understanding of the at45db operation is as follows:
- You need to do an ERASE before writing (which surprisingly takes a few
microseconds).
- When you do a WRITE operation, you are writing a page (max 256 bytes) or
two pages (256 to 512 bytes) to the dedicated buffers of the at45db chip.
(This operation takes 12 ms for 256 bytes)
- At this stage if you keep on writing you will override the data in the
dedicated buffers again and again.
- To Write data from the buffers to the physical flash you need to do a SYNC
operation. Now data is stored (non volatile). (This takes about 17.5 ms for
any size).
- To Read data from a page, the physical flash memory is accessed, and
through the buffers data is retrieved. (This takes around 3.5ms for 256
bytes).
- The specs for the at45db chip indicate that the chip consumes: Read
Operation (from 7-15 mA depending on the frequency) and Program/Erase
Operation (from 12 to 17 mA).

I wonder:
- What is the current employed for the WRITE operation (since it only
accesses the buffers)?
- What is the current for the SYNC operation? I guess that would be the
Program/Erase current.
- Is the ERASE operation so fast due to the fact that it is only used to set
some flag and indeed it does not Erase the flash page?

Thanks in advance,
Ricardo
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