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IN r,(C)

Load register r from port (C).
Function: r <- (C)
 
Format:
1110 1101
 
byte 1: ED
 
01rr r000
 
byte 2
 
Description: The peripheral device addressed by the contents of the C register is read and the result is loaded into the specified register.
C provides bits A0 to A7 of the address bus.
B provides bits A8 to A15
Data Flow:
 
Timing: 3 M cycles; 12 T states: 6 usec @ 2 MHz
 
Addressing Mode: external
 
Byte Codes:
 
Flags:
It is important to note that IN A,(N) does not have any effect on the flags, while IN r,(C) does.
 
Example:

OBJECT CODE
Before:
 
After: