PXR40RM Datasheet, PDF (1371/1434 Pages) Freescale Semiconductor, Inc – PXR40 Microcontroller

Nexus Development Interface (NDI)
31.14.7.2 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 e200z7 Nexus1 module. The e200z7 Nexus1
module is capable of setting multiple address and/or data watchpoints. Please see the e200z7 Core
Reference Manual for more information 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 e200z7 defined watchpoints can be programmed to assert the event out EVTO
pin for one period of the output clock (MCKO).
Watchpoint information is messaged out in the following format:
3
2
1
WPHIT
SRC
TCODE (001111)
msb
4 bits
4 bits
6 bits
lsb
Fixed length = 14 bits
Figure 31-37. Watchpoint Message Format.
Table 31-29. Watchpoint Source Encoding
Watchpoint Source
(8 bits)
00000001
00000010
00000100
00001000
00010000
00100000
01000000
10000000
Watchpoint Description
e200z7 Watchpoint #0 (IAC1 from Nexus1)
e200z7 Watchpoint #1 (IAC2 from Nexus1)
e200z7 Watchpoint #2 (IAC3 from Nexus1)
e200z7 Watchpoint #3 (IAC4 from Nexus1)
e200z7 Watchpoint #4 (DAC1 from Nexus1)
e200z7 Watchpoint #5 (DAC2 from Nexus1)
e200z7 Watchpoint #6 (DCNT1 from Nexus1)
e200z7 Watchpoint #7 (DCNT2 from Nexus1)
31.14.7.3 Watchpoint Error Message
An error message occurs when a new message cannot be queued due to the message queue being full. The
FIFO discards messages until it has completely emptied the queue. After it is emptied, an error message is
queued. The error encoding indicates the types of messages that attempted to be queued while the FIFO
was being emptied.
If only a watchpoint message attempts to enter the queue while it is being emptied, the error message
incorporates the watchpoint only error encoding (00110). If an OTM and/or program trace and/or data
trace message also attempts to enter the queue while it is being emptied, the error message incorporates
error encoding (01000).
Freescale Semiconductor
PXR40 Microcontroller Reference Manual, Rev. 1
31-55