NEC PD750008 - Manual (Page 313)

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CHAPTER 11 INSTRUCTION SET
PUSH BS
Function: (SP–1) <– MBS, (SP–2) <– RBS, SP <– SP–2
Saves the contents of the memory bank select register (MBS) and the register bank select register (RBS)
to the data memory location (stack) addressed by the stack pointer (SP), then decrements SP.
POP rp
Function: rp
L
<– (SP), rp
H
<– (SP+1), SP <– SP+2
Restores register pair rp (XA, HL, DE, BC) with the data at the data memory location (stack) addressed
by the stack pointer (SP), then increments SP.
The low-order part of a register pair (rp
L
: A, L, E, C) is restored from the contents of (SP), and the high-
order part (rp
H
: X, H, D, B) is restored with the contents of (SP+ ).
POP BS
Function: RBS <– (SP), MBS <– (SP+1), SP <– SP+2
Restores the register bank select register (RBS) and the memory bank select register (MBS) with the data
at the data memory location (stack) addressed by the stack pointer (SP), then increments SP.
11.4.12 Interrupt Control Instructions
EI
Function: IME (IPS.3) <– 1
Sets the interrupt master enable flag (bit 3 of the interrupt priority specification register) to 1 to enable
interrupts. Whether to accept an interrupt is controlled with the corresponding interrupt enable flag.
EI IExxx
Function: IExxx <– 1 xxx = N
5
, N
2-0
Sets an interrupt enable flag (IExxx) to 1 to enable an interrupt. (xxx = BT, CSI, T0, T1, W, 0, 1, 2, 4)
DI
Function: IME (IPS.3) <– 0
Resets the interrupt master enable flag (bit 3 of the interrupt priority specification register) to 0 to disable
all interrupts regardless of the states of the interrupt enable flags.