INSTRUCTION DESCRIPTIONS
A - 90
INSTRUCTION SET DETAILS
MOTOROLA
ing the last instruction in the DO loop. Note that LF is the only bit in the status register
(SR) that is restored after a hardware DO loop has been exited.
Note: The loop flag (LF) is cleared by a hardware reset.
Restrictions: The “end-of-loop” comparison previously described actually occurs at
instruction fetch time. That is, LA is being compared with PC when the instruction at LA–
2 is being executed. Therefore, instructions which access the program controller regis-
ters and/or change program flow cannot be used in locations LA–2, LA–1, or LA.
Proper DO loop operation is not guaranteed if an instruction starting at address LA–2,
LA–1, or LA specifies one of the program controller registers SR, SP, SSL, LA, LC, or
(implicitly) PC as a destination register. Similarly, the SSH program controller register
may not be specified as a source or destination register in an instruction starting at
address LA–2, LA–1, or LA. Additionally, the SSH register cannot be specified as a
source register in the DO instruction itself and LA cannot be used as a target for jumps
to subroutine (i.e., JSR, JScc, JSSET, or JSCLR to LA). A DO instruction cannot be
repeated using the REP instruction.
The following instructions cannot begin at the indicated position(s) near the end of a DO
loop:
At LA–2, LA–1, and LA
DO
MOVEC from SSH
MOVEM from SSH
MOVEP from SSH
MOVEC to LA, LC, SR, SP, SSH, or SSL
MOVEM to LA, LC, SR, SP, SSH, or SSL
MOVEP to LA, LC, SR, SP, SSH, or SSL
ANDI MR
ORI MR
Two-word instructions which read LC, SP, or SSL
At LA–1
Single-word instructions (except REP) which read LC,
SP, or SSL, JCLR, JSET, two-word JMP, two-word Jcc
DO
Start Hardware Loop
DO
Summary of Contents for DSP56K
Page 12: ...xii LIST of TABLES MOTOROLA List of Tables Continued Table Page Number Title Number ...
Page 13: ...MOTOROLA DSP56K FAMILY INTRODUCTION 1 1 SECTION 1 DSP56K FAMILY INTRODUCTION ...
Page 31: ...MOTOROLA DATA ARITHMETIC LOGIC UNIT 3 1 SECTION 3 DATA ARITHMETIC LOGIC UNIT ...
Page 50: ...DATA ALU SUMMARY 3 20 DATA ARITHMETIC LOGIC UNIT MOTOROLA ...
Page 51: ...MOTOROLA ADDRESS GENERATION UNIT 4 1 SECTION 4 ADDRESS GENERATION UNIT ...
Page 77: ...MOTOROLA PROGRAM CONTROL UNIT 5 1 SECTION 5 PROGRAM CONTROL UNIT ...
Page 124: ...INSTRUCTION GROUPS 6 30 INSTRUCTION SET INTRODUCTION MOTOROLA ...
Page 125: ...MOTOROLA PROCESSING STATES 7 1 SECTION 7 PROCESSING STATES STOP WAIT EXCEPTION NORMAL RESET ...
Page 167: ...STOP PROCESSING STATE MOTOROLA PROCESSING STATES 7 43 ...
Page 168: ...STOP PROCESSING STATE 7 44 PROCESSING STATES MOTOROLA ...
Page 169: ...MOTOROLA PORT A 8 1 SECTION 8 PORT A ...
Page 176: ...PORT A INTERFACE 8 8 PORT A MOTOROLA ...
Page 177: ...MOTOROLA PLL CLOCK OSCILLATOR 9 1 SECTION 9 PLL CLOCK OSCILLATOR x x d Φ VCO ...
Page 191: ...10 2 ON CHIP EMULATION OnCE MOTOROLA SECTION 10 ON CHIP EMULATION OnCE ...
Page 218: ...USING THE OnCE MOTOROLA ON CHIP EMULATION OnCE 10 29 ...
Page 604: ...INSTRUCTION ENCODING A 338 INSTRUCTION SET DETAILS MOTOROLA ...
Page 605: ...MOTOROLA BENCHMARK PROGRAMS B 1 APPENDIX B BENCHMARK PROGRAMS T T T T T P1 P3 P2 P4 T T T ...
Page 609: ...BENCHMARK PROGRAMS MOTOROLA BENCHMARK PROGRAMS B 5 ...
Page 611: ...BENCHMARK PROGRAMS MOTOROLA BENCHMARK PROGRAMS B 7 ...
Page 613: ...BENCHMARK PROGRAMS MOTOROLA BENCHMARK PROGRAMS B 9 ...
Page 615: ...BENCHMARK PROGRAMS MOTOROLA BENCHMARK PROGRAMS B 11 ...