General-Purpose Registers; Data To Be Saved To Stack Memory; Data To Be Restored From Stack Memory - NEC 78K/0S Series User Manual

−
SP SP 2
Lower byte in
−
SP 2
register pair
Upper byte in
−
SP 1
register pair
SP
POP rp
instruction
Lower byte in
SP
register pair
Upper byte in
SP + 1
register pair
SP SP + 2

2.2 General-Purpose Registers

The general-purpose register consists of eight 8-bit registers (X, A, C, B, E, D, L, and H).
Each register can be used as an 8-bit register, or two 8-bit registers in pairs can be used as a 16-bit register (AX,
BC, DE, and HL).
Registers can be described in terms of functional names (X, A, C, B, E, D, L, H, AX, BC, DE, and HL) and
absolute names (R0 to R7 and RP0 to RP3).
CHAPTER 2 REGISTERS
Figure 2-4. Data to Be Saved to Stack Memory
PUSH rp
instruction
SP SP
SP
SP
SP
Figure 2-5. Data to Be Restored from Stack Memory
SP
SP + 1
SP SP + 2
User's Manual U11047EJ3V0UM00
CALL, CALLT
instructions
−
2
−
2
PC7 to PC0
−
1
PC15 to PC8
RET instruction
PC7 to PC0
PC15 to PC8
Interrupt
−
SP SP 3
−
SP 3
PC7 to PC0
−
SP 2
PC15 to PC8
−
SP 1
PSW
SP
RETI instruction
SP
PC7 to PC0
SP + 1
PC15 to PC8
SP + 2
PSW
SP SP + 3
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