MC9S08AW16CFUE Datasheet, PDF (282/324 Pages) Freescale Semiconductor, Inc – MC9S08AW60 Features

Chapter 15 Development Support
15.4.3.9 Debug Status Register (DBGS)
This is a read-only status register.
7
R
AF
6
5
4
3
2
BF
ARMF
0
CNT3
CNT2
W
Reset
0
0
0
0
0
0
= Unimplemented or Reserved
Figure 15-9. Debug Status Register (DBGS)
1
CNT1
0
0
CNT0
0
Table 15-6. DBGS Register Field Descriptions
Field
Description
7
AF
6
BF
5
ARMF
3:0
CNT[3:0]
Trigger Match A Flag — AF is cleared at the start of a debug run and indicates whether a trigger match A
condition was met since arming.
0 Comparator A has not matched
1 Comparator A match
Trigger Match B Flag — BF is cleared at the start of a debug run and indicates whether a trigger match B
condition was met since arming.
0 Comparator B has not matched
1 Comparator B match
Arm Flag — While DBGEN = 1, this status bit is a read-only image of ARM in DBGC. This bit is set by writing 1
to the ARM control bit in DBGC (while DBGEN = 1) and is automatically cleared at the end of a debug run. A
debug run is completed when the FIFO is full (begin trace) or when a trigger event is detected (end trace). A
debug run can also be ended manually by writing 0 to ARM or DBGEN in DBGC.
0 Debugger not armed
1 Debugger armed
FIFO Valid Count — These bits are cleared at the start of a debug run and indicate the number of words of valid
data in the FIFO at the end of a debug run. The value in CNT does not decrement as data is read out of the FIFO.
The external debug host is responsible for keeping track of the count as information is read out of the FIFO.
0000 Number of valid words in FIFO = No valid data
0001 Number of valid words in FIFO = 1
0010 Number of valid words in FIFO = 2
0011 Number of valid words in FIFO = 3
0100 Number of valid words in FIFO = 4
0101 Number of valid words in FIFO = 5
0110 Number of valid words in FIFO = 6
0111 Number of valid words in FIFO = 7
1000 Number of valid words in FIFO = 8
MC9S08AW60 Data Sheet, Rev 2
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