ADSP-BF535 Blackfin Processor Hardware Reference
20-5
Blackfin Processor’s Debug
On the ADSP-BF535 processor, code patching can be achieved by writing
the start address of the earlier code to one of the
WPIAx
registers and set-
ting the corresponding
EMUSWx
bit to trigger an exception. In the exception
service routine, the
WPSTAT
register is read to determine which watchpoint
triggered the exception. Next, the code writes the start address of the new
code in the
RETX
register and then returns from the exception to the new
code. Because the exception mechanism is used for code patching, event
service routines of the same or higher priority (exception, NMI, and reset
routines) cannot be patched.
A write to the
WPSTAT
MMR clears all the sticky status bits. The data value
written is ignored.
Watchpoint Instruction Address Registers (WPIAx)
When the Watchpoint Unit is enabled, the values in the
WPIAx
registers
are compared to the address on the instruction bus. Corresponding count
values in the Watchpoint Instruction Address Count registers (
WPIACNTx
)
are decremented on each match.
Figure 20-1
shows the Watchpoint Instruction Address registers,
WPIA[5:0]
.
Figure 20-1. Watchpoint Instruction Address Registers
X
15 14
13 12
11 10
9
8
7
6
5
4
3
2
1
0
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
31 30
29 28
27 26
25 24
23 22
21 20
19
18 17 16
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Watchpoint Instruction Address Registers (WPIAx)
Reset = Undefined
WPIA (Instruction Address)[30:15]
WPIA (Instruction Address)[14:0]
For MMR assign-
ments, see
Table 20-4
.
Summary of Contents for ADSP-BF535 Blackfin
Page 80: ...Development Tools 1 26 ADSP BF535 Blackfin Processor Hardware Reference...
Page 312: ...Working With Memory 6 86 ADSP BF535 Blackfin Processor Hardware Reference...
Page 332: ...System Interfaces 7 20 ADSP BF535 Blackfin Processor Hardware Reference...
Page 360: ...Dynamic Power Management Controller 8 28 ADSP BF535 Blackfin Processor Hardware Reference...
Page 446: ...Beginning and Ending an SPI Transfer 10 40 ADSP BF535 Blackfin Processor Hardware Reference...
Page 522: ...Timing Examples 11 76 ADSP BF535 Blackfin Processor Hardware Reference...
Page 562: ...IrDA Support 12 40 ADSP BF535 Blackfin Processor Hardware Reference...
Page 608: ...PCI I O Issues 13 46 ADSP BF535 Blackfin Processor Hardware Reference...
Page 672: ...References 14 64 ADSP BF535 Blackfin Processor Hardware Reference...
Page 810: ...SDRAM Controller SDC 18 86 ADSP BF535 Blackfin Processor Hardware Reference...
Page 811: ...ADSP BF535 Blackfin Processor Hardware Reference 18 87 External Bus Interface Unit...
Page 812: ...SDRAM Controller SDC 18 88 ADSP BF535 Blackfin Processor Hardware Reference...
Page 860: ...DMA Bus Debug Registers 20 30 ADSP BF535 Blackfin Processor Hardware Reference...