9: Debugging Your System
ARM720T CORE CPU MANUAL EPSON 9-1
9Debugging Y our System
This chapter describes how to debug a system based on an ARM720T processor. It contains the
following sections:
9.1 About debugging your system ................................................................... 9-2
9.2 Controlling debugging................................................................................ 9-3
9.3 Entry into debug state ............................................................................... 9-5
9.4 Debug interface .......................................................................................... 9-9
9.5 ARM720T core clock domains.................................................................... 9-9
9.6 The EmbeddedICE-RT macrocell ............................................................ 9-10
9.7 Disabling EmbeddedICE-RT ....................................................................9-11
9.8 EmbeddedICE-RT register map .............................................................. 9-12
9.9 Monitor mode debugging ......................................................................... 9-12
9.10 The debug communications channel ....................................................... 9-14
9.11 Scan chains and the JTAG interface....................................................... 9-17
9.12 The TAP controller ................................................................................... 9-19
9.13 Public JTAG instructions.......................................................... ..... .... .... .. 9-20
9.14 Test data registers....................................................................................9-22
9.15 Scan timing............................................................................................... 9-25
9.16 Examining the core and the system in debug state ............................... 9-26
9.17 Exit from debug state................................... .... .... ..... .... .... .... .... ..... .... .... .. 9-29
9.18 The program counter during debug......................................................... 9-30
9.19 Priorities and exceptions.......................................................................... 9-32
9.20 Watchpoint unit registers ........................................................................ 9-33
9.21 Programming breakpoints ....................................................................... 9-36
9.22 Programming watchpoints....................................................................... 9-38
9.23 Abort status register ................................................................................ 9-38
9.24 Debug control register.............................................................................. 9-39
9.25 Debug status register............................................................................... 9-41
9.26 Coupling breakpoints and watchpoints ..................................................9-43
9.27 EmbeddedICE-RT timing ........................................................................9-44