NEC PD750004 Manuale Utente

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CHAPTER 11  INSTRUCTION SET
Caution Before this instruction can be executed, MBE = 0 or (MBE = 1, MBS = 15) must be set.
Only 4 or 6 can be specified as n.
11.4.14   CPU Control Instructions
HALT
Function:  PCC.2 <– 1
Sets the HALT mode.  (This instruction is used to set bit 2 of the processor clock control register.)
Caution The instruction immediately following a HALT instruction must be a NOP instruction.
STOP
Function:  PCC.3 <– 1
Sets the STOP mode.  (This instruction is used to set  bit 3 of the processor clock control register.)
Caution The instruction immediately following a STOP instruction must be a NOP instruction.
NOP
Function:  Uses one machine cycle without performing an action.
11.4.15   Special Instructions
SEL RBn
Function:  RBS <– n     n = N
1-0
:  0 to 3
Sets the 2-bit immediate data n in the register bank select register (RBS).
SEL MBn
Function:  MBS <– n     n = N
3-0
:  0, 1, 15
Transfers the 4-bit immediate data n to the memory bank select register (MBS).
Only 0, 1, or 15 can be specified as n.