Intel 8XC251SA, User Manual

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C-7
REGISTERS
ACC
Address: E0H
Reset State: 0000 0000B
Accumulator. ACC provides SFR access to the accumulator, which resides in the register file as byte
register R11 (also named ACC). Instructions in the MCS
®
51 architecture use the accumulator as both
source and destination for calculations and moves. Instructions in the MCS 251 architecture assign no
special significance to R11. These instructions can use byte registers Rm (m = 0–15) interchangeably.
7 0
Accumulator Contents
Bit
Number
Bit
Mnemonic
Function
7:0 ACC.7:0 Accumulator.
B
Address: F0H
Reset State: 0000 0000B
B Register. The B register provides SFR access to byte register R10 (also named B) in the register
file. The B register is used as both a source and destination in multiply and divide operations. For all
other operations, the B register is available for use as one of the byte registers Rm, m = 0–15.
7 0
B Register Contents
Bit
Number
Bit
Mnemonic
Function
7:0 B.7:0 B Register.