Lpc2000

Guido,

The RTCK (output from ARM) is a synchronized TCK (input to ARM).
The RTCK is used by the synthesized ARM cores (they usually have the -S suffix)
to synchronize the external JTAG TCK clock with the internal core clock.
Besides the need to synchronize the clocks, the added benefit is that the emulator
can now follow any changes in clock speed of the ARM device.
A lot of devices these days a battery powered and the ARM clock is being
lowered from hundreds of MHz to kHz range to reduce power draw.
This feature is sometimes called Adaptive Clocking by the emulator companies
and is available on most higher end JTAG emulators.

Jerry Lewandowski
Signum Systems Corp.
11992 Challenger Ct.
Moorpark, CA 93021
Tel. (805) 523-9774
www.signum.com
==============================================
     26 YEARS OF EMULATION SYSTEMS DESIGN: 
  8051, ARM, OMAP, 80186, 80196 and TMS320 DSPs
==============================================



----- Original Message ----- 
From: "Soentgerath, Guido" <Guido.Soentgerath@...>
To: <lpc2000@yahoogroups.com>
Sent: Wednesday, January 18, 2006 1:05 AM
Subject: [lpc2000] JTAG - RTCK ?


> Hello all,
> can someone give me an explanation for RTCK  or  a hint where I can find
> some more infos about this signal ?
> Thanks in advance!
>  
> Regards,
> Guido
> 
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> Yahoo! Groups Links
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