Memory Block; Block Locking - Nokia 616 Service Manual

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The power save (PS) function is only active in burst mode due to delay in the readings
(Random access). If it were used in random access, it would have introduced a delay of
10 – 15 ns. The PS is not activated in the first access in the burst, only from the second
access in the burst.
In particular in burst mode it is important to keep the performance. In order to reduce
complexity in the memory, the power save function does not apply to the address. This
means that the address will always be presented in its true value. This means that the
memory do not have to manage the inversion of the address. In case of burst access it is
possible to reduce the power on the external bus by comparing the contents of the data
in the burst, not with the data on the bus. This results in that the random access data is
presented on the bus, as such but the following data in the burst is presented using the
power save function. By pipelining the power save information in this manner the addi-
tional delay caused by the comparison logic is removed.

Memory block.

The memory or flash is organized in four Banks, A, B, C and D. Bank A and B each contain
eight 8 Kword sectors and thirty-one 32 Kword sectors. Bank C and D each contain
thirty-two 32 Kword sectors. The total sector Architecture is eight 8 Kword sectors and
one hundred twenty-six 32 Kword sectors.

Block locking.

To prevent accidental writings to some of the sectors in the flash, block locking has to be
used. This can, depending on the vendor, bee implemented by using different methods.
AMD and Intel are the to only vendors that Triton is going to use for the flash purpose.
AMD and Intel will implement their block locking in the following way.
Intel: The locking scheme offers two levels of protection. The first allows software-only
control of block locking (useful for frequently changed data blocks) while the second
requires hardware interaction before locking can be changed (protects infrequently
changed code blocks). For this purpose, a dedicated pin called WP is used. The WP-pin or
signal is only controlled by the hardware.
Lock block:
The blocks' default power-up or reset status is locked. Locked blocks are fully protected
from alteration. Attempted program or erase operations to a locked block will return an
error in a status register inside the flash. A locked block's status can be changed to
unlocked or lock-down using the appropriate software commands. Writing the "Lock
block command" sequence can lock an unlocked block.
Unlock block:
Unlocked blocks can be programmed or erased. All unlocked blocks return to the locked
state when the phone is or powered down. An unlocked block's status can be changed to
the locked or locked-down state using the appropriate software commands. A locked
block can be unlocked by writing a "unlock block command" sequence, if the block is not
locked-down.
Issue 2.0 Mar/2005
Company Confidential
Copyright © 2005 Nokia Corporation.
Company Confidential
TFE-4/RV-1
TF4 Technical Information
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