Development Support
MPC561/MPC563 Reference Manual, Rev. 1.2
23-36
Freescale Semiconductor
Data values in the last two functions other than those specified are reserved.
All transmissions from the debug port on DSDO begin with a “0” or “ready” bit. This indicates that the
CPU is trying to read an instruction or data from the port. The external development tool must wait until
it sees DSDO go low to begin sending the next transmission.
The control bit differentiates between instructions and data and allows the development port to detect that
an instruction was entered when the CPU was expecting data and vice versa. If this occurs a sequence error
indication is shifted out in the next serial transmission.
The trap enable function allows the development tool to transfer data to the trap enable control register.
The debug port command function allows the development tool to either negate breakpoint requests, reset
the processor, activate or deactivate the fast down load procedure.
The NOP function provides a null operation for use when there is data or a response to be shifted out of
the data register and the appropriate next instruction or command will be determined by the value of the
response or data shifted out.
23.4.6.10 Serial Data Out of Development Port
The encoding of data shifted out of the development port shift register in debug mode (through the DSDO
pin) is the same as for trap enable mode and is shown in
.
Valid data encoding is used when data has been transferred from the CPU to the development port shift
register. This is the result of an instruction to move the contents of a general purpose register to the debug
port data register (DPDR). The valid data encoding has the highest priority of all status outputs and will
be reported even if an interrupt occurs at the same time. Since it is not possible for a sequencing error to
occur and also have valid data there is no priority conflict with the sequencing error status. Also, any
interrupt that is recognized at the same time that there is valid data is not related to the execution of an
Table 23-13. Debug Instructions / Data Shifted into Development Port Shift Register
Start
Mode
Control
Instruction / Data (32 Bits)
Function
Bits 0:6
Bits 7:31
1
0
0
CPU Instruction
Transfer Instruction
to CPU
1
0
1
CPU Data
Transfer Data
to CPU
1
1
0
Trap enable
1
1
Refer to
Does not exist
Transfer data to
Trap Enable
Control Register
1
1
1
0011111
Does not exist
Negate breakpoint requests
to the CPU.
1
1
1
0
Does not exist
NOP
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...