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RRD

Rotate right decimal.
Function:
 
Format:
1110 1101
 
byte 1: ED
 
0110 0111
 
byte 2: 67
 
Description: The 4 high order bits of the memory location addressed by the contents of the HL register pair are moved to the low order 4 bits of that location. The 4 low order bits are moved to the 4 low order bits of the accumulator. The low order bits of the accumulator are moved to the 4 high order bit positions of the memory location originally specified. All the above operations occur simultaneously.
 
Data Flow:
 
Timing: 5 M cycles; 18 T states: 9 usec @ 2 MHz
 
Addressing Mode: indirect
 
Flags:
 
Example:
RRD

OBJECT CODE
Before:
 
After: