NXP Semiconductors MKW01Z128, Reference Manual

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15.3.2.2 MTB_DWT Comparator Register (MTBDWT_COMPn)
The MTBDWT_COMPn registers provide the reference value for comparator n.
Address: F000_1000h base + 20h (16d × i), where i=0d to 1d
Bit 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
R
COMP
W
Reset
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
MTBDWT_COMPn field descriptions
Field Description
COMP Reference value for comparison
If MTBDWT_COMP0 is used for a data value comparator and the access size is byte or halfword, the data
value must be replicated across all appropriate byte lanes of this register. For example, if the data is a
byte-sized "x" value, then COMP[31:24] = COMP[23:16] = COMP[15:8] = COMP[7:0] = "x". Likewise, if the
data is a halfword-size "y" value, then COMP[31:16] = COMP[15:0] = "y".
15.3.2.3 MTB_DWT Comparator Mask Register (MTBDWT_MASKn)
The MTBDWT_MASKn registers define the size of the ignore mask applied to the
reference address for address range matching by comparator n. Note the format of this
mask field is different than the MTB_MASTER[MASK].
Address: F000_1000h base + 24h (16d × i), where i=0d to 1d
Bit 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
R
0
MASK
W
Reset
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
MTBDWT_MASKn field descriptions
Field Description
31–5
Reserved
This field is reserved.
This read-only field is reserved and always has the value 0.
MASK MASK
The value of the ignore mask, 0-31 bits, is applied to address range matching. MASK = 0 is used to
include all bits of the address in the comparison, except if MASK = 0 and the comparator is configured to
watch instruction fetch addresses, address bit [0] is ignored by the hardware since all fetches must be at
least halfword aligned. For MASK != 0 and regardless of watch type, address bits [x-1:0] are ignored in the
address comparison.
Using a mask means the comparator matches on a range of addresses, defined by the unmasked most
significant bits of the address, bits [31:x]. The maximum MASK value is 24, producing a 16 Mbyte mask.
An attempted write of a MASK value > 24 is limited by the MTBDWT hardware to 24.
Table continues on the next page...
Chapter 15 Micro Trace Buffer (MTB)
MKW01Z128 MCU Reference Manual, Rev. 3, 04/2016
Freescale Semiconductor, Inc. 277