Lauterbach C6000, Manual

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C6000 Debugger | 46
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Lauterbach
SYStem.LOCK Tristate the JTAG port
Default: OFF.
If the system is locked, no access to the JTAG port will be performed by the debugger. While locked the
JTAG connector of the debugger is tristated. The intention of the
SYStem.LOCK command is, for example,
to give JTAG access to another tool. The process can also be automated, see SYStem.CONFIG TriState .
It must be ensured that the state of the TI DSP core JTAG state machine remains unchanged while the
system is locked. To ensure correct hand-over, the options
SYStem.CONFIG TAPState and
SYStem.CONFIG TCKLevel must be set properly. They define the TAP state and TCK level which is
selected when the debugger switches to tristate mode. Please note: nTRST must have a pull-up resistor on
the target.
ARTCK Accelerated method to control the debug clock by the RTCK signal
(Accelerated Returned TCK). This option is only relevant for JTAG debug
ports.
The RTCK mode allows theoretical frequencies up to 1/6 (ARM7, ARM9) or
1/8 (ARM11) of the processor clock. For designs using a very low processor
clock we offer a different mode (ARTCK) which does not work as
recommended by ARM and might not work on all target systems.
In ARTCK mode, the debugger uses a fixed frequency for TCK, independent
of the RTCK signal. This frequency must be specified by the user and has to
be below 1/3 of the processor clock speed. TDI and TMS will be delayed by
1/2 TCK clock cycle. TDO will be sampled with RTCK.
CTCK With this option higher debug port speeds can be reached. The
TDO/SWDIO signal will be sampled by a signal which derives from
TCK/SWCLK, but which is timely compensated regarding the debugger-
internal driver propagation delays (
C ompensation by TCK ). This feature
can be used with a debug cable version 3 or newer. If it is selected,
although the debug cable is not suitable, a fixed frequency will be selected
instead (minimum of 10 MHz and selected clock).
CRTCK With this option higher debug port speeds can be reached. The TDO/SWDIO
signal will be sampled by the RTCK signal. This compensates the debugger-
internal driver propagation delays, the delays on the cable and on the target
(
C ompensation by RTCK ). This feature requires that the target provides an
RTCK signal. In contrast to the RTCK option, the TCK/SWCLK is always
output with the selected, fixed frequency.
Format: SYStem.LOCK [ ON | OFF ]