Miscellaneous Instructions

 i) PUSH

  • Syntax: PUSH reg. pair
  • e.g. PUSH B
Before instruction
B=32, C=57
SP=2099
After instruction
M [2097]=57
M [2098]=32
SP=2097

ii) POP
  • Syntax: POP reg. pair
  • e.g. POP H
Before instruction
SP=2090
M [2090]=F5
M [2091]=01
After instruction
H=01
L=F5
SP=2092
iii) EI
  • Enabling interrupts
iv) DI
  • Disabling interrupts
v) PCHL
  • The contents of registers H and L are copied to the program counter.
vi) SPHL
  • The contents of registers H and L are copied to the stack pointer register.
vii) XTHL
  • Exchange H and L with Top of Stack

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