Renesas SH7641 - Manual (Page 172)

Section 3 DSP Operation
Rev. 4.00 Sep. 14, 2005 Page 122 of 982
REJ09B0023-0400
3.1.10 Local Data Move Instruction
The DSP unit of this LSI provides additional two independent registers, MACL and MACH, in
order to support SH's standard multiply/MAC operations. They can be also used as temporary
storage registers by local data move instructions between MACH/L and other DSP registers Figure
3.17 shows the flow of seven local data move instructions. Table 3.13 shows the variation of this
type of instruction.
PLDS PSTS
Cannot be used
X0
X1
MACH
MACL
Y0
Y1
M0
M1
A0
A1
A0G A1G DSR
Figure 3.17 Local Data Move Instruction Flow
Table 3.13 Variation of Local Data Move Operations
Mnemonic Function Operand
PLDS Data move from DSP register to MACL/MACH Dz
PSTS Data move from MACL/MACH to DSP register Dz
This instruction is very similar to other transfer instructions. If either the A0 or A1 register is
specified as the destination operand of PSTS, the signed bit is sign-extended and copied into the
corresponding guard-bit parts, A0G or A1G. The DC bit in DSR and other condition code bits are
not updated regardless of the instruction result. This instruction can operate with MOVX and
MOVY in parallel.