Analog Devices ADSP-BF53x Blackfin Reference page 211

The User Stack Pointer register and the Supervisor Stack Pointer register
are accessed using the register alias
sor operating mode, only one of these registers is active and accessible as
:
SP
• In User mode, any reference to
R0 = [ SP++ ] ;
• In Supervisor mode, the same reference to
R0 = [ SP++ ] ;
the effective address.
To manipulate the User Stack Pointer for code running in Supervi-
sor mode, use the register alias
register move from
rent User Stack Pointer into
used in Supervisor mode.
Some load/store instructions use
• -indexed load/store, which extends the addressing range for
FP
16-bit encoded load/stores
• Stack push/pop instructions, including those for pushing and pop-
ping multiple registers
• Link/unlink instructions, which control stack frame space and
manage the Frame Pointer register (
ADSP-BF53x/BF56x Blackfin Processor Programming Reference
. Depending on the current proces-
SP
(for example, stack pop
SP
) implicitly uses the
) implicitly uses the Supervisor Stack Pointer as
. When in Supervisor mode, a
USP
(for example,
USP
. The register alias
R0
and
FP SP
Address Arithmetic Unit
as the effective address.
USP
(for example,
SP
) moves the cur-
R0 = USP ;
USP
implicitly:
) for that space
FP
can only be
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