Development Support
MPC561/MPC563 Reference Manual, Rev. 1.2
23-6
Freescale Semiconductor
11. Negate VSYNC
12. Return to the regular code run (issue an rfi). The first report on the VF pins is a VSYNC (VF = 011)
13. The external hardware stops sampling the program trace information upon the report on the VF
pins of VSYNC
23.1.4.2
Detecting the Trace Window Start Address
When using back trace, latching the value of the status pins (VF and VFLS), and the address of the cycles
marked as program trace cycle, should start immediately after the negation of reset. The start address is
the first address in the program trace cycle buffer.
When using window trace, latching the value of the status pins (VF and VFLS), and the address of the
cycles marked as program trace cycle, should start immediately after the first VSYNC is reported on the
VF pins. The start address of the trace window should be calculated according to first two VF pins reports.
Assuming that VF1 and VF2 are the two first VF pins reports and T1 and T2 are the two addresses of the
first two cycles marked with the program trace cycle attribute that were latched in the trace buffer, use the
following table to calculate the trace window start address.
23.1.4.3
Detecting the Assertion/Negation of VSYNC
Since the VF pins are used for reporting both instruction type information and queue flush information,
the external hardware must take special care when trying to detect the assertion/negation of VSYNC.
When VF = 011 it is a VSYNC assertion/negation report only if the previous VF pins value was one of the
following values: 000, 001, or 010.
23.1.4.4
Detecting the Trace Window End Address
The information on the status pins that describes the last fetched instruction and the last queue/history
buffer flushes, changes every clock. Cycles marked as program trace cycle are generated on the external
bus only when possible (when the SIU wins the arbitration over the external bus). Therefore, there is some
delay between the information reported on the status pins that a cycle marked as program trace cycle will
be performed on the external bus and the actual time that this cycle can be detected on the external bus.
When VSYNC is negated (through the serial interface of the development port), the CPU delays the report
of the of the assertion/negation of VSYNC on the VF pins (VF = 011) until all addresses marked with the
program trace cycle attribute were visible externally. Therefore, the external hardware should stop
Table 23-4. Detecting the Trace Buffer Start Point
VF1
VF2
Starting point
Description
011
VSYNC
001
sequential
T1
VSYNC asserted followed by a sequential instruction.
The start address is T1
011
VSYNC
110
branch direct taken
T1 - 4 +
offset (T1 - 4)
VSYNC asserted followed by a taken direct branch.
The start address is the target of the direct branch
011
VSYNC
101
branch indirect taken
T2
VSYNC asserted followed by a taken indirect branch.
The start address is the target of the indirect branch
Summary of Contents for MPC561
Page 84: ...MPC561 MPC563 Reference Manual Rev 1 2 lxxxiv Freescale Semiconductor...
Page 144: ...Signal Descriptions MPC561 MPC563 Reference Manual Rev 1 2 2 46 Freescale Semiconductor...
Page 206: ...Central Processing Unit MPC561 MPC563 Reference Manual Rev 1 2 3 62 Freescale Semiconductor...
Page 302: ...Reset MPC561 MPC563 Reference Manual Rev 1 2 7 14 Freescale Semiconductor...
Page 854: ...Time Processor Unit 3 MPC561 MPC563 Reference Manual Rev 1 2 19 24 Freescale Semiconductor...
Page 968: ...Development Support MPC561 MPC563 Reference Manual Rev 1 2 23 54 Freescale Semiconductor...
Page 1144: ...Internal Memory Map MPC561 MPC563 Reference Manual Rev 1 2 B 34 Freescale Semiconductor...
Page 1212: ...TPU3 ROM Functions MPC561 MPC563 Reference Manual Rev 1 2 D 60 Freescale Semiconductor...
Page 1216: ...Memory Access Timing MPC561 MPC563 Reference Manual Rev 1 2 E 4 Freescale Semiconductor...