
MOTOROLA
Chapter 24. READI Module
24-77
Watchpoint Support
watchpoints occur, a message is sent to the signal output formatter to be messaged out (the
general message queue is bypassed to prevent watchpoint messages from being cancelled
in the event of a queue overflow). The watchpoint message has the second highest priority.
watchpoint message contains the watchpoint code which indicates all the unique
watchpoints have occurred since the last watchpoint message. If duplicate watchpoints
occur before the watchpoint message is sent out, a watchpoint overrun message is
generated. The watchpoint source field will indicate which watchpoints occurred.
The watchpoint message has the following format:
Figure 24-70. Watchpoint Message Format
24.12.1.1 Watchpoint Source Field
24.12.2
Watchpoint Overrun Error Message
A watchpoint overrun error occurs when the same watchpoint occurs multiple times before
the first occurrence of that watchpoint has been messaged out. The watchpoint message
(which has information of all the watchpoints that occurred prior to the detection of the
same watchpoint occurring multiple times) will be sent before the error message can be
sent.
The overrun error causes further watchpoint occurrences to be ignored, until the error
message has been sent. The error code within the error message indicates that a watchpoint
The error message has the following format:
Table 24-32. Watchpoint Source
Watchpoint Source
Description
0bXXXXX1
First L-bus watchpoint (LW0)
0bXXXX1X
Second L-bus watchpoint (LW1)
0bXXX1XX
First I-bus watchpoint (IW0)
0bXX1XXX
Second I-bus watchpoint (IW1)
0bX1XXXX
Third I-bus watchpoint (IW2)
0b1XXXXX
Fourth I-bus watchpoint (IW3)
Length = 12 bits
TCODE (15)
Watchpoint Source
[6 bits]