Infineon Technologies C166S V2 User Manual page 353

CoMACMRus
Group
Syntax
Source Operand(s)
Destination Operand(s)
Operation
(tmp) ← ((op1)) * ((op2))
(ACC) ← (tmp) - (ACC)
((IDXi(-*))) ← ((IDXi))
Description
Multiplies the two unsigned and signed 16-bit source operands op1 and op2,
respectively. The resulting signed 32-bit product is first sign-extended; then, the 40-bit
ACC register contents are subtracted from the result before being stored in the 40-bit
ACC register. In parallel to the arithmetic operation and to the two parallel reads, the
data pointed to by IDXi overwrites another data located in memory (DPRAM). The
address of the overwritten data depends on the operation executed on IDXi.
MAC Flags
MV MSL
* *
MV Set if an arithmetic underflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic underflow occurred. Not affected otherwise.
MC Set if a borrow is generated. Cleared otherwise.
MZ Set if result equals zero. Cleared otherwise.
MN Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoMACMRus [IDXi*], [Rw
User Manual
Multiply-Accumulate & Move
Multiply/Multiply-Accumulate Instructions
CoMACMRus op1, op2
op1, op2 → WORD
ACC → 40-bit signed value
ME MSV
* *
*]
m
Detailed Instruction Description
MC MZ
* *
Format
93 Xm B8 rrr0:0qqq
8-353
User Manual
C166S V2
CoMACMRus
MN Sat.
* yes
Bytes
4
V 1.7, 2001-01