Table of Contents
MOTOROLA
M68060 USER’S MANUAL
xv
8.3
8.4
8.4.1
8.4.2
8.4.3
8.4.4
8.4.4.1
8.4.4.2
8.4.4.3
8.4.5
8.4.6
8.4.7
Exception Priorities .....................................................................................8-17
Return from Exceptions ..............................................................................8-19
Four-Word Stack Frame (Format $0) .......................................................8-19
Six-Word Stack Frame (Format $2)..........................................................8-20
Floating-Point Post-Instruction Stack Frame (Format $3) ........................8-20
Eight-Word Stack Frame (Format $4).......................................................8-21
Program Counter (PC)............................................................................8-21
Fault Address .........................................................................................8-22
Fault Status Long Word (FSLW).............................................................8-22
Recovering from an Access Error.............................................................8-25
Bus Errors and Pending Memory Writes .................................................8-27
Branch Prediction Error ............................................................................8-29
Section 9
IEEE 1149.1 Test (JTAG) and Debug Pipe Control Modes
IEEE 1149.1 Test Access Port (Normal JTAG) Mode ..................................9-1
Overview.....................................................................................................9-2
JTAG Instruction Shift Register ..................................................................9-3
EXTEST....................................................................................................9-4
LPSAMPLE...............................................................................................9-5
Private Instructions...................................................................................9-5
SAMPLE/PRELOAD.................................................................................9-5
IDCODE....................................................................................................9-5
CLAMP .....................................................................................................9-6
HIGHZ.......................................................................................................9-6
BYPASS ...................................................................................................9-6
JTAG Test Data Registers..........................................................................9-7
Idcode Register ........................................................................................9-7
Boundary Scan Register...........................................................................9-7
Bypass Register .....................................................................................9-15
Restrictions...............................................................................................9-15
Disabling the IEEE 1149.1 Standard Operation .......................................9-15
Motorola MC68060 BSDL Description......................................................9-17
Debug Pipe Control Mode...........................................................................9-24
Debug Command Interface.......................................................................9-25
Debug Pipe Control Mode Commands.....................................................9-27
Emulator Mode .........................................................................................9-31
Switching between JTAG and Debug Pipe ControlModes of Operation.....9-33
9.1
9.1.1
9.1.2
9.1.2.1
9.1.2.2
9.1.2.3
9.1.2.4
9.1.2.5
9.1.2.6
9.1.2.7
9.1.2.8
9.1.3
9.1.3.1
9.1.3.2
9.1.3.3
9.1.4
9.1.5
9.1.6
9.2
9.2.1
9.2.2
9.2.3
9.3
Section 10
Instruction Execution Timing
10.1
10.1.1
Superscalar Operand Execution Pipelines .................................................10-1
Dispatch Test 1: sOEP Opword and Required
Extension Words Are Valid.......................................................................10-2
Dispatch Test 2: Instruction Classification................................................10-2
10.1.2