NXP Semiconductors PXN2020, Reference Manual, Page: 1176 / 1376

Nexus Development Interface (NDI)
PXN20 Microcontroller Reference Manual, Rev. 1
36-26 Freescale Semiconductor
36.6.4 Features
The module is compliant with Class 3 of the IEEE

-ISTO 5001-2003 standard. The following
features are implemented:
• Program trace via branch trace messaging (BTM). Branch trace messaging displays program flow
discontinuities (direct and indirect branches, exceptions, etc.), allowing the development tool to
interpolate what transpires between the discontinuities. Thus static code may be traced.
• Data trace via data write messaging (DWM) and data read messaging (DRM). This provides the
capability for the development tool to trace reads and/or writes to selected internal memory
resources.
• Ownership trace via ownership trace messaging (OTM). OTM facilitates ownership trace by
providing visibility of which process ID or operating system task is activated. An ownership trace
message is transmitted when a new process/task is activated, allowing the development tool to
trace ownership flow.
• Run-time access to embedded processor registers and memory map via the JTAG port. This allows
for enhanced download/upload capabilities.
• Watchpoint messaging via the auxiliary pins.
• Watchpoint trigger enable of Program and/or Data Trace Messaging.
• Higher speed data input/output via the auxiliary port.
• Registers for Program Trace, Data Trace, Ownership Trace and Watchpoint Trigger.
• All features controllable and configurable via the JTAG port.
JTAG Compliant Device complying to IEEE

1149.1 JTAG standard
JTAG IR & DR Sequence JTAG instruction register (IR) scan to load an opcode value for selecting a development
register. The JTAG IR corresponds to the OnCE command register (OCMD). The selected
development register is then accessed via a JTAG data register (DR) scan.
Nexus1 The e200z6 (OnCE) debug module. This module integrated with each e200z6 processor
provides all static (core halted) debug functionality. This module is compliant with Class1 of the
IEEE

-ISTO 5001 standard.
Ownership Trace
Message (OTM)
Visibility of process/function that is currently executing.
Public Messages Messages on the auxiliary pins for accomplishing common visibility and controllability
requirements
Standard The phrase ‘according to the standard’ is used to indicate according to the IEEE

-ISTO 5001
standard.
Transfer Code (TCODE) Message header that identifies the number and/or size of packets to be transferred, and how
to interpret each of the packets.
Watchpoint A data or instruction breakpoint that does not cause the processor to halt. Instead, a pin is used
to signal that the condition occurred. A watchpoint message is also generated.
Table 36-13. Terms and Definitions (continued)
Term Description