Maxim Integrated MAXQ610 - Manual (Page 189)

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MAXQ610 User’s Guide
SLA/SLA2/SLA4 Shift Accumulator Left Arithmetically One, Two, or Four Times
Description: Shifts the active accumulator left once, twice, or four times respectively for SLA, SLA2, and SLA4 .
For each shift iteration, a 0 is shifted into the lsbit and the msbit is shifted into the Carry (C) flag . For
signed data, this shifting process effectively retains the sign orientation of the data to the point at
which overflow/underflow would occur .
Status Flags: C, S, Z
SLA Carry Flag 15 Active Accumulator (Acc) 0
Operation: ← ← ←
0
C ← Acc .15; Acc .[15:1] ← Acc .[14:0]; Acc .0 ← 0
Encoding: 15 0
1000 1010 0010 1010
Example(s): ; Acc = E345h, C=0, S=1, Z=0
SLA ; Acc = C68Ah, C=1, S=1, Z=0
SLA ; Acc = 8D14h, C=1, S=1, Z=0
SLA2 Carry Flag 15 Active Accumulator (Acc) 0
Operation: ← ← ←
0
C ← Acc .14; Acc .[15:2] ← Acc .[13:0]; Acc .[1:0] ← 0
Encoding: 15 0
1000 1010 0011 1010
Example(s): ; Acc = E345h, C=0, S=1, Z=0
SLA2 ; Acc = 8D14h, C=1, S=1, Z=0
SLA4 Carry Flag 15 Active Accumulator (Acc) 0
Operation: ← ← ←
0
C ← Acc .12; Acc .[15:4] ← Acc .[11:0]; Acc .[3:0] ← 0
Encoding: 15 0
1000 1010 0110 1010
Example(s): ; Acc = E345h, C=0, S=1, Z=0
SLA4 ; Acc = 3450h, C=0, S=0, Z=0