Texas Instruments MSC1210 - Manual (Page 294)

8052 Instruction Set
E-10
DJNZ Decrement and Jump if Not Zero
Syntax DJNZ register,relAddr
Instructions OpCode Bytes Cycles Flags
DJNZ direct,relAddr 0xD5 3 2 None
DJNZ R0,relAddr 0xD8 2 2 None
DJNZ R1,relAddr 0xD9 2 2 None
DJNZ R2,relAddr 0xDA 2 2 None
DJNZ R3,relAddr 0xDB 2 2 None
DJNZ R4,relAddr 0xDC 2 2 None
DJNZ R5,relAddr 0xDD 2 2 None
DJNZ R6,relAddr 0xDE 2 2 None
DJNZ R7,relAddr 0xDF 2 2 None
DJNZ decrements the value of register by 1. If the initial value of register is 0,
decrementing the value causes it to reset to 255 (0xFF
H
). If the new value of
register is not 0, the program branchs to the address indicated by relAddr. If
the new value of register is 0, program flow continues with the instruction fol-
lowing the DJNZ instruction.
See also: DEC, JZ, JNZ