Embedded Trace Macrocell
ARM DDI 0500D Copyright © 2013-2014 ARM. All rights reserved. 13-33
ID021414 Non-Confidential
Table 13-25 shows the TRCCNTCTLR1 bit assignments.
The TRCCNTCTLR1 can be accessed through the internal memory-mapped interface and the
external debug interface, offset
0x154
.
13.8.23 Counter Value Registers 0-1
The TRCCNTVRn characteristics are:
Purpose Contains the current counter value.
Usage constraints • Can be written only when the ETM trace unit is disabled.
• The count value is stable only when TRCSTATR.PMSTABLE==1.
• If software uses counter <n>, then it must write to this register to set
the initial counter value.
Configurations Available in all configurations.
Attributes See the register summary in Table 13-3 on page 13-10.
Table 13-25 TRCCNTCTLR1 bit assignments
Bits Name Function
[31:18] - Reserved,
RES0.
[17] CNTCHAIN Defines whether the counter decrements when the counter reloads. This enables two counters to be used in
combination to provide a larger counter:
0
The counter operates independently from the counter. The counter only decrements based
on CNTTYPE and CNTSEL.
1
The counter decrements when the counter reloads. The counter also decrements when the
resource selected by CNTTYPE and CNTSEL is active.
[16] RLDSELF Defines whether the counter reloads when it reaches zero:
0
The counter does not reload when it reaches zero. The counter only reloads based on
RLDTYPE and RLDSEL.
1
The counter reloads when it is zero and the resource selected by CNTTYPE and CNTSEL
is also active. The counter also reloads based on RLDTYPE and RLDSEL.
[15] RLDTYPE Selects the resource type for the reload:
0
Single selected resource.
1
Boolean combined resource pair.
[14:12] - Reserved,
RES0.
[11:8] RLDSEL Selects the resource number, based on the value of RLDTYPE:
When RLDTYPE is 0, selects a single selected resource from 0-15 defined by bits[3:0].
When RLDTYPE is 1, selects a Boolean combined resource pair from 0-7 defined by bits[2:0].
[7] CNTTYPE Selects the resource type for the counter:
0
Single selected resource.
1
Boolean combined resource pair.
[6:4] - Reserved,
RES0.
[3:0] CNTSEL Selects the resource number, based on the value of CNTTYPE:
When CNTTYPE is 0, selects a single selected resource from 0-15 defined by bits[3:0].
When CNTTYPE is 1, selects a Boolean combined resource pair from 0-7 defined by bits[2:0].
To Next Page
Loading...
