Freescale Semiconductor e200z3 Reference Manual page 407

10.9 Watchpoint Support
This section details the watchpoint features of the Nexus3/Nexus2+ module.
10.9.1 Overview
The Nexus3/Nexus2+ module provides watchpoint messaging by means of the auxiliary pins, as defined
by the IEEE-ISTO 5001-2003 standard.
Nexus3/Nexus2+ is not compliant with class 4 breakpoint/watchpoint requirements defined in the
standard. The breakpoint/watchpoint control register is not implemented.
10.9.2 Watchpoint Messaging
Enabling watchpoint messaging is done by setting the watchpoint enable bit in the DC1 register. Setting
the individual watchpoint sources is supported through the e200z3 Nexus1 module. The e200z3 Nexus1
module is capable of setting multiple address and/or data watchpoints. Please refer to
Support," for details on watchpoint initialization.
When these watchpoints occur, a watchpoint event signal from the Nexus1 module causes a message to be
sent to the queue to be messaged out. This message includes the watchpoint number indicating which
watchpoint caused the message.
The occurrence of any of the e200z3-defined watchpoints can be programmed to assert the event out,
nex_evto_b, pin for one period of the output clock, nex_mcko; see
Watchpoint information is messaged out in the format shown in
Watchpoint Source (8-Bits)
Freescale Semiconductor
(8 bit)
Watchpoint Source
Fixed length = 18 bits
Figure 10-39. Watchpoint Message Format.
Table 10-27. Watchpoint Source Encoding
0000_0001 e200z3 watchpoint #0 (IAC1 from Nexus1)
0000_0010 e200z3 watchpoint #1 (IAC2 from Nexus1)
0000_0100 e200z3 watchpoint #2 (IAC3 from Nexus1)
0000_1000 e200z3 watchpoint #3 (IAC4 from Nexus1)
0001_0000 e200z3 watchpoint #4 (DAC1 from Nexus1)
0010_0000 e200z3 watchpoint #5 (DAC2 from Nexus1)
e200z3 Power Architecture Core Reference Manual, Rev. 2
Table 10-31
Figure 10-39:
(4 bits) (6 bits)
Source Process TCODE (001111)
Watchpoint Description
Nexus3/Nexus2+ Module
Chapter 9, "Debug
for details on nex_evto_b.
10-41