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Debug Support
MCF5272 ColdFire
®
Integrated Microprocessor User’s Manual, Rev. 3
Freescale Semiconductor
5-7
5.4.1
Revision A Shared Debug Resources
In the Revision A implementation of the debug module, certain hardware structures are shared between
BDM and breakpoint functionality as shown in
.
Thus, loading a register to perform a specific function that shares hardware resources is destructive to the
shared function. For example, a BDM command to access memory overwrites an address breakpoint in
ABHR. A BDM write command overwrites the data breakpoint in DBR.
5.4.2
Address Attribute Trigger Register (AATR)
The address attribute trigger register (AATR),
, defines address attributes and a mask to be
matched in the trigger. The register value is compared with address attribute signals from the processor’s
local high-speed bus, as defined by the setting of the trigger definition register (TDR).
describes AATR fields
.
Table 5-4. Rev. A Shared BDM/Breakpoint Hardware
Register
BDM Function
Breakpoint Function
AATR
Bus attributes for all memory commands
Attributes for address breakpoint
ABHR
Address for all memory commands
Address for address breakpoint
DBR
Data for all BDM write commands
Data for data breakpoint
15
14
13
12
11
10
8
7
6
5
4
3
2
0
Field RM
SZM
TTM
TMM
R
SZ
TT
TM
Reset
0000_0000_0000_0101
R/W Write only. AATR is accessible in supervisor mode as debug control register 0x06 using the WDEBUG
instruction and through the BDM port using the
WDMREG
command.
DRc[4–0]
0x06
Figure 5-5. Address Attribute Trigger Register (AATR)
Table 5-5. AATR Field Descriptions
Bits
Name Description
15
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 Longword
01 Byte
10 Word
11 Reserved