Freescale Semiconductor MPC5565, Reference Manual

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Nexus
MPC5565 Microcontroller Reference Manual, Rev. 1.0
Freescale Semiconductor 24-91
The Nexus module provides watchpoint messaging using the TCODE. When either of the two possible
watchpoint sources asserts, a message will be sent to the queue to be messaged out. This message indicates
the watchpoint number.
Figure 24-69. Watchpoint Message Format
24.14.6.2 Watchpoint Error Message
An error message occurs when a new message cannot be queued due to the message queue being full. The
FIFO will discard messages until it has completely emptied the queue. After it is emptied, an error message
will be queued. The error encoding will indicate which types of messages 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 will
incorporate the watchpoint only error encoding (00110). If a data trace message also attempts to enter the
queue while it is being emptied, the error message will incorporate error encoding (01000).
Error information is messaged out in the following format (refer to Figure 24-70 ).
Figure 24-70. Error Message Format
Table 24-61. Watchpoint Source Description
Watchpoint Source (4 bits) Watchpoint Description
XXX1 Reserved
XX1X Reserved
X1XX Internal Watchpoint #1 (BWA1 match)
1XXX Internal Watchpoint #2 (BWA2 match)
WPHIT (XXXX)
MSB LSB
1 2
SRC TCODE (001111)
3
6 bits 4 bits 4 bits
Fixed length = 14 bits
ECODE (00110 / 01000)
MSB LSB
1 2
SRC TCODE (001000)
3
6 bits 4 bits 5 bits
Fixed length = 15 bits