DCR

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Syntax: DCR R
Where R can be any of the general purpose registers (A,B,C,D,E,H andL)
Byte: 1byte
Addressing Mode: Register Addressing

Working: 
1. 
2. 
3. 
4. Flag

Example: DCR B 
Where [B]= 10H
After execution of DCR B
 [B]= 0F H


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