Motorola DSP56000 Manual page 55

SECTION 4.1 ADDRESS GENERATION UNIT AND ADDRESSING MODES ....3
SECTION 4.2 AGU ARCHITECTURE ..................................................................3
4.2.1 Address Register Files (Rn) ................................................................3
4.2.2 Offset Register Files (Nn) ....................................................................4
4.2.3 Modifier Register Files (Mn) ................................................................5
4.2.4 Address ALU .......................................................................................5
4.2.5 Address Output Multiplexers ...............................................................6
SECTION 4.3 PROGRAMMING MODEL .............................................................6
4.3.1 Address Register Files (R0 - R3 and R4 - R7) ....................................7
4.3.2 Offset Register Files (N0 - N3 and N4 - N7) .......................................7
4.3.3 Modifier Register Files (M0 - M3 and M4 - M7) ...................................8
SECTION 4.4 ADDRESSING ...............................................................................8
4.4.1 Address Register Indirect Modes ........................................................9
4.4.1.1 No Update ................................................................................... 9
4.4.1.2 Postincrement By 1 ..................................................................... 9
4.4.1.3 Postdecrement By 1 ................................................................... 9
4.4.1.4 Postincrement By Offset Nn ....................................................... 10
4.4.1.5 Postdecrement By Offset Nn ...................................................... 11
4.4.1.6 Indexed By Offset Nn .................................................................. 12
4.4.1.7 Predecrement By 1 ..................................................................... 13
4.4.2 Address Modifier Arithmetic Types .....................................................14
4.4.2.1 Linear Modifier (Mn=$FFFF) ....................................................... 16
4.4.2.2 Modulo Modifier .......................................................................... 18
4.4.2.3 Reverse-Carry Modifier (Mn=$0000) .......................................... 22
4.4.2.4 Address-Modifier-Type Encoding Summary ............................... 25
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SECTION CONTENTS
ADDRESS GENERATION UNIT MOTOROLA