PDSP1601_96 Datasheet, PDF (10/18 Pages) Mitel Networks Corporation – ALU and Barrel Shifter

PDSP1601/PDSP1601A
INSTRUCTION SET
ALU Arithmetic Instructions
Mnemonic Op Code
Function
CLRXX
<00>
On the rising edge of CLK at the end of the cycle in which this instruction is executing, the
A Port, B Port, ALU, Barrel Shifter, and Shift Control Registers will be loaded with zeros.
The internal registered CO will also be set to zero, and the BFP flag will be set to activate
on overflow conditions.
MIAX1
MIAC1
MIACO
<01>
<02>
<03>
The A input to the ALU is inverted and a one is added to the LSB.
The A input to the ALU is inverted and the CI input is added to the LSB.
The A input to the ALU is inverted and the CO output from the ALU on the previous cycle
is added to the LSB.
A2SGN
<04>
The A input to the ALU is right shifted one bit position. The LSB is discarded, and the vacant
MSB is filled by duplicating the original MSB (Sign Extension).
A2RAL
<05>
The A input to the ALU is right shifted one bit position. The LSB is discarded, and the vacant
MSB is filled with the LSB from the ALU register.
A2RAR
<06>
The A input to the ALU is right shifted one bit position. The LSB is discarded, and the vacant
MSB is filled with the LSB from the ALU register.
A2RSX
<07>
The A input to the ALU is right shifted one bit position. The LSB is discarded, and the vacant
MSB is filled with the LSB from the B input to the ALU.
APBCI
APBCO
<08>
<09>
The A input to the ALU is added to the B input, and the CI input is added to the LSB.
The A input to the ALU is added to the B input, and the CO out from the ALU on the previous
cycle is added to the LSB.
AMBX1
AMBCI
<0A>
<0B>
The A input to the ALU is added to the inverted B input, and a one is added to the LSB.
The A input to the ALU is added to the inverted B input, and the CI input is added to the
LSB.
AMBCO
<0C>
The A input to the ALU is added to the inverted B input, and the CO out from the ALU on
the previous cycle is added to the LSB.
BMAX1
BMAC1
<0D>
<0E>
The inverted A input to the ALU is added to the B input, and a one is added to the LSB.
The inverted A input to the ALU is added to the B input, and the CI input is added to the
LSB.
BMACO
<0F>
The inverted A input to the ALU is added to the B input, and the CO out from the ALU on
the previous cycle is added to the LSB.
ALU Logical Instructions
Mnemonic ^{Op Code}
ANXAB
<10>
ANANB
<11>
ANNAB
<12>
ORXAB
<13>
ORNAB
<14>
XORAB
<15>
PASXA
<16>
PASNA
<17>
Function
The A input to the ALU is logically 'ANDed' with the B input.
The A input to the ALU is logically 'ANDed' with the inverse of the B input.
The inverse of the A input to the ALU is logically 'ANDed' with the B input.
The A input to the ALU is logically 'ORed' with the B input.
The inverse A input to the ALU is logically 'ORed' with the B input.
The A input to the ALU is logically Exclusive-ORed with the B input.
The A input to the ALU is passed to the output.
The inverse of the A input to the ALU is passed to the output.
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