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ADD IY,rr

Add IY and register pair rr.
Function: IY <- IY + rr
 
Format:
1111 1101
 
byte 1: FD
 
00rr 1001
 
byte 2
 
Description: The contents of the IY register are added to the contents of the specified register pair and the result is stored back in IY. rr may be any one of:
BC
00
DE
01
IY
10
SP
11

 
Data Flow:
 
Timing: 4 M cycles; 15 T states: 7.5 usec @ 2 MHz
 
Addressing Mode: implicit
 
Byte Codes:
ADD IY,rr
ss:BCDEIYSP
FD +09192939
 
Flags:
C is set by carry from bit 15, reset otherwise.
H is set by a carry from bit 11.
 
Example:
ADD  IY,DE

OBJECT CODE
Before:
 
After: