PD77210_15 Datasheet, PDF (43/76 Pages) Renesas Technology Corp – 16-BIT FIXED-POINT DIGITAL SIGNAL PROCESSOR

µPD77210, 77213
(b) Modifying data pointer
The data pointer is modified only after memory access. The result of the modification becomes valid starting
from the instruction that is executed immediately after. The data pointer cannot be modified without the
memory access.
Example
DPn
DPn++
DPn−−
DPn##
DPn%%
!DPn##
DPn## imm
Operation
Nothing is executed (value of DPn is not changed).
DPn ← DPn + 1
DPn ← DPn − 1
DPn ← DPn + DNn
(Value of DN0 to DN7 corresponding to DP0 to DP7 is added.)
Example: DP0 ← DP0 + DN0
(n = 0 to 3) DPn = ((DPL + DNn) mod (DMX + 1)) + DPH
(n = 4 to 7) DPn = ((DPL + DNn) mod (DMY + 1)) + DPH
Reverses bits of DPn and then accesses DPn.
After memory access, DPn ← DPn + DNn
DPn ← DPn + imm
(c) Instructions that can be described simultaneously
Those instructions that can be described simultaneously are indicated by √.
(d) Status of overflow flag (OV)
The status of the overflow flag is indicated by the following symbols:
: No change
: Set to 1 if an overflow occurs.
Caution If an overflow does not occur after an operation, the overflow flag is not reset and its status
remains the same as before the operation.
Data Sheet U15203EJ3V0DS
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