Specifications

Table Of Contents
ARM Debugger 80 ARM specific SYStem Commands
©1989-2014 Lauterbach GmbH
ARTCK: Accelerated method to control the JTAG clock by the RTCK signal (Accelerated Returned TCK).
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 JTAG 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 JTAG speeds can be reached. The TDO signal will be sampled by a signal
which derives from TCK, but which is timely compensated regarding the debugger internal driver
propagation delays (Compensation by TCK). This feature can be used with a debug cable versions 3b or
newer. If it is selected, although the debug cable is not suitable, a fix JTAG clock will be selected instead
(minimum of 10 MHz and selected clock).
CRTCK: With this option higher JTAG speeds can be reached. The TDO 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 (Compensation by RTCK). This feature requires that the target provides a RTCK signal.
Other as on RTCK option, the TCK is always output with the selected, fix frequency.
The mode ARTCK can not be used if a DEBUG INTERFACE (LA-7701) or a
debug cable with 14-pin flat cable (LA-7740) is used. And it is required that the
target provides a RTCK signal.
The mode CTCK can not be used if a DEBUG INTERFACE (LA-7701) is used.
This feature can be used with a debug cable versions 3 or newer.
The mode CRTCK can not be used if a DEBUG INTERFACE (LA-7701) or a
debug cable with 14-pin flat cable (LA-7740) is used. And it is required that the
target provides a RTCK signal.