GR740-UM-DS, Nov 2017, Version 1.7
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GR740
33.6.2 Time tag counter register
The trace buffer time tag counter is incremented each clock as long as the processor is running. The
counter is stopped when the processor enters debug mode (unless the timer enable bit in the AHB
trace buffer control register is set), and restarted when execution is resumed. The value of this register
is used as time tag in the instruction and AHB trace buffers. The same time source is used for the pro-
cessors’ internal up-counters.
33.6.3 DSU Break and Single Step register
This register is used to break or single step the processors. This register controls all processors in a
multi-processor system, and is only accessible in the DSU memory map of processor 0.
33.6.4 DSU Debug Mode Mask Register
When one of the processors in a multiprocessor LEON4 system enters the debug mode the value of
the DSU Debug Mode Mask register determines if the other processors are forced in the debug mode.
This register controls all processors in a multi-processor system, and is only accessible in the DSU
memory map of processor 0.
Table 525.
0x000008 - DTTC - DSU time tag counter register
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
TIMETAG
0
rw
31: 0
DSU Time Tag Value (TIMETAG)
Table 526.
0x000020 - BRSS - DSU break and single step register
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
RESERVED
SS[3:0]
RESERVED
BN[3:0]
0
0
0
*
r
rw
r
rw
31: 17
RESERVED
19: 16
Single step (SSx) - if set, the processor x will execute one instruction and return to debug mode. The
bit remains set after the processor goes into the debug mode.
15: 4
RESERVED
3:0
Break now (BNx) -Force processor x into debug mode if the Break on watchpoint (BW) bit in the
processors DSU control register is set. If cleared, the processor x will resume execution.
The reset value of this field is taken from the external BREAK signal.
Table 527.
0x000024 - DBGM - DSU debug mode mask register
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
RESERVED
DM[3:0]
RESERVED
ED[3:0]
0
0
0
0
r
rw
r
rw
31: 17
RESERVED
19: 16
Debug mode mask (DMx) - If set, the corresponding processor will not be able to force running pro-
cessors into debug mode even if it enters debug mode.
15: 4
RESERVED
3:0
Enter debug mode (EDx) - Force processor x into debug mode if any of processors in a multiproces-
sor system enters the debug mode. If 0, the processor x will not enter the debug mode.