MPC555
/
MPC556
DEVELOPMENT SUPPORT
MOTOROLA
USER’S MANUAL
Rev. 15 October 2000
21-53
21.7.10 Breakpoint Counter B Value and Control Register
COUNTB[16:31] are cleared following reset; COUNTB[0:15] are unaffected by reset.
21.7.11 Exception Cause Register (ECR)
The ECR indicates the cause of entry into debug mode. All bits are set by the hardware
and cleared when the register is read when debug mode is disabled, or if the processor
is in debug mode. Attempts to write to this register are ignored. When the hardware
sets a bit in this register, debug mode is entered only if debug mode is enabled and
the corresponding mask bit in the DER is set.
All bits are cleared to zero following reset.
COUNTB —
Breakpoint Counter B Value and Control Register
SPR 151
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
CNTV
RESET: UNAFFECTED
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
RESERVED
CNTC
RESET:
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Table 21-26 Breakpoint Counter B Value and Control Register (COUNTB)
Bit(s)
Name
Description
0:15
CNTV
Counter preset value
16:29
—
Reserved
30:31
CNTC
Counter source select
00 = not active (reset value)
01 = I-bus second watchpoint
10 = L-bus second watchpoint
11 = Reserved
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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