CPL - Z80 instruction reference

cplComplement A 
Inverts every bit of A, giving its one's complement.
1 byte · 4 cycles
Used in 8-bit and 16-bit arithmetic, logic and bitsZ80 assembly
 
SZHP/VNC ––1–1–
1 always 1
– not changed
Forms  cpl  
The contents of A are inverted (one's complement).
         .org 0x8000
        ld a, 5
        cpl
        halt