PXN20RM Datasheet, PDF (1163/1376 Pages) Freescale Semiconductor, Inc – PXN20 Microcontroller

Nexus Development Interface (NDI)
- Using Nexus Read/Write Access,
Configure the CRP Z0VEC register
- Select DBCR0 Register.
- Set DEVT2 Bit
NPC
Z0
Z6
Z0, Z6 Multi
- Select OnCE CMD register.
- Set EX bit to exit debug mode.
- Select DBSR
- Write to DEVT2 bit to clear it.
Z6 Breakpoint
reached or
entered debug
mode?
Yes Z0 enters Debug
Mode
- Select OnCE Control Register (OCR)
- Set DR bit (request debug mode right
out of reset).
Figure 36-4. Flow for Enabling e200z0 to put the e200z6 into Debug Mode (Continued)
The flow for enabling the e200z6 Nexus3+ to cause a debug request to the e200z0 is similar.
36.5 Nexus Port Controller (NPC)
The Nexus Port Controller (NPC) is that part of the NDI that controls access and arbitration of the device’s
internal Nexus modules. The NPC contains the port configuration register (PCR) and the device
identification register (DID). The contents of the NPC DID are the same as the JTAGC device
identification register.
36.5.1 NPC Overview
The PXN20 incorporates multiple modules that require development support. Each of these modules
implements a development interface based on the IEEE-ISTO 5001-2001 standard and must share the
input and output ports that interface with the development tool. The NPC controls the usage of these ports
Freescale Semiconductor
PXN20 Microcontroller Reference Manual, Rev. 1
36-13