Debug SupportMCF5272 ColdFire ® Integrated Microprocessor User’s Manual, Rev. 3Freescale Semiconductor 5-75.4.1 Revision A Shared Debug ResourcesIn the Revision A implementation of the debug module, certain hardware structures are shared betweenBDM and breakpoint functionality as shown in Table 5-4.Thus, loading a register to perform a specific function that shares hardware resources is destructive to theshared function. For example, a BDM command to access memory overwrites an address breakpoint inABHR. A BDM write command overwrites the data breakpoint in DBR.5.4.2 Address Attribute Trigger Register (AATR)The address attribute trigger register (AATR), Figure 5-5, defines address attributes and a mask to bematched in the trigger. The register value is compared with address attribute signals from the processor’slocal high-speed bus, as defined by the setting of the trigger definition register (TDR).Table 5-5 describes AATR fields.Table 5-4. Rev. A Shared BDM/Breakpoint HardwareRegister BDM Function Breakpoint FunctionAATR Bus attributes for all memory commands Attributes for address breakpointABHR Address for all memory commands Address for address breakpointDBR Data for all BDM write commands Data for data breakpoint15 14 13 12 11 10 8 7 6 5 4 3 2 0Field RM SZM TTM TMM R SZ TT TMReset 0000_0000_0000_0101R/W Write only. AATR is accessible in supervisor mode as debug control register 0x06 using the WDEBUGinstruction and through the BDM port using the WDMREG command.DRc[4–0] 0x06Figure 5-5. Address Attribute Trigger Register (AATR)Table 5-5. AATR Field DescriptionsBits Name Description15 RM Read/write mask. Setting RM masks R in address comparisons.14–13 SZM Size mask. Setting an SZM bit masks the corresponding SZ bit in address comparisons.12–11 TTM Transfer type mask. Setting a TTM bit masks the corresponding TT bit in address comparisons.10–8 TMM Transfer modifier mask. Setting a TMM bit masks the corresponding TM bit in address comparisons.7 R Read/write. R is compared with the R/W signal of the processor’s local bus.6–5 SZ Size. Compared to the processor’s local bus size signals.00 Longword01 Byte10 Word11 Reserved
