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
JTAG - RTCK ?
Started by ●January 18, 2006
Reply by ●January 18, 20062006-01-18
----- Original Message -----
From: "Soentgerath, Guido" <Guido.Soentgerath@Guid...>
To: <lpc2000@lpc2...>
Sent: Wednesday, January 18, 2006 9:05 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!
I found a document on the ARM web site a long time ago which describes the
JTAG interface in detail. Can't remember where, though.
Leon
From: "Soentgerath, Guido" <Guido.Soentgerath@Guid...>
To: <lpc2000@lpc2...>
Sent: Wednesday, January 18, 2006 9:05 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!
I found a document on the ARM web site a long time ago which describes the
JTAG interface in detail. Can't remember where, though.
Leon
Reply by ●January 18, 20062006-01-18
Soentgerath, Guido wrote:
>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! RTCK is an optional JTAG signal. According to the Abatron BDI2000 manual:
"Adaptive clocking is a feature which ensures that the BDI2000 never
loses synchronization wih the target device, whatever the target clock
speed is. To achive this, BDI2000 uses two signals TCK and RTCK. When
adaptive clocking is selected, BDI2000 issues a TCK signal and waits for
the Returned TCK (RTCK) to come back. BDI2000 does not progress to the
next TCK until RTCK is received." TomW
--
Tom Walsh - WN3L - Embedded Systems Consultant
http://openhardware.net, http://cyberiansoftware.com
"Windows? No thanks, I have work to do..."
----------------
>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! RTCK is an optional JTAG signal. According to the Abatron BDI2000 manual:
"Adaptive clocking is a feature which ensures that the BDI2000 never
loses synchronization wih the target device, whatever the target clock
speed is. To achive this, BDI2000 uses two signals TCK and RTCK. When
adaptive clocking is selected, BDI2000 issues a TCK signal and waits for
the Returned TCK (RTCK) to come back. BDI2000 does not progress to the
next TCK until RTCK is received." TomW
--
Tom Walsh - WN3L - Embedded Systems Consultant
http://openhardware.net, http://cyberiansoftware.com
"Windows? No thanks, I have work to do..."
----------------
Reply by ●January 18, 20062006-01-18
It is the Return Clock. It is used for deglitching the return signal.
Ideally, the chip under test would have zero delay getting the clock on
board. But it does have some delay. The RTCK is the image to of the
JTAG clock being used by the chip. For very fast clocking, this allows
the debugger to sync up with the chip under test.
_____
From: lpc2000@lpc2... [mailto:lpc2000@lpc2...] On Behalf
Of Leon Heller
Sent: Wednesday, January 18, 2006 3:03 AM
To: lpc2000@lpc2...
Subject: Re: [lpc2000] JTAG - RTCK ?
----- Original Message -----
From: "Soentgerath, Guido" <Guido.Soentgerath@Guid...>
To: <lpc2000@lpc2...>
Sent: Wednesday, January 18, 2006 9:05 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!
I found a document on the ARM web site a long time ago which describes
the
JTAG interface in detail. Can't remember where, though.
Leon
_____
> .
_____
Ideally, the chip under test would have zero delay getting the clock on
board. But it does have some delay. The RTCK is the image to of the
JTAG clock being used by the chip. For very fast clocking, this allows
the debugger to sync up with the chip under test.
_____
From: lpc2000@lpc2... [mailto:lpc2000@lpc2...] On Behalf
Of Leon Heller
Sent: Wednesday, January 18, 2006 3:03 AM
To: lpc2000@lpc2...
Subject: Re: [lpc2000] JTAG - RTCK ?
----- Original Message -----
From: "Soentgerath, Guido" <Guido.Soentgerath@Guid...>
To: <lpc2000@lpc2...>
Sent: Wednesday, January 18, 2006 9:05 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!
I found a document on the ARM web site a long time ago which describes
the
JTAG interface in detail. Can't remember where, though.
Leon
_____
> .
_____
Reply by ●January 18, 20062006-01-18
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@Guid...>
To: <lpc2000@lpc2...>
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 >
> Yahoo! Groups Links >
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@Guid...>
To: <lpc2000@lpc2...>
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 >
> Yahoo! Groups Links >
Reply by ●January 18, 20062006-01-18
Tom, Guido,
From the BDI2000 this may be an optional signal. On the LPC21xx it must
be used.
The RTCK signal is described in the ARM7 TDMI-S manual that can be found
on the ARM website.
Check the website for a link or browse the archive - it's been mentioned
a few times.
If you do not use the RTCK signal - or cannot use that signal because it
is unsupported on your JTAG debugger - make sure that the JTAG CLK is
lower than 1/6 of the CCLK of the lpc21xx, otherwise the timing is
screwed. See the ARM manual for detailed information - it even contains
some schematics on how the RTCK is generated in the processor.
Regards,
Rob
Tom Walsh wrote:
>Soentgerath, Guido wrote: >
>>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!
>>
>>
>>
>>
>RTCK is an optional JTAG signal. According to the Abatron BDI2000 manual:
>
>"Adaptive clocking is a feature which ensures that the BDI2000 never
>loses synchronization wih the target device, whatever the target clock
>speed is. To achive this, BDI2000 uses two signals TCK and RTCK. When
>adaptive clocking is selected, BDI2000 issues a TCK signal and waits for
>the Returned TCK (RTCK) to come back. BDI2000 does not progress to the
>next TCK until RTCK is received." >TomW >
From the BDI2000 this may be an optional signal. On the LPC21xx it must
be used.
The RTCK signal is described in the ARM7 TDMI-S manual that can be found
on the ARM website.
Check the website for a link or browse the archive - it's been mentioned
a few times.
If you do not use the RTCK signal - or cannot use that signal because it
is unsupported on your JTAG debugger - make sure that the JTAG CLK is
lower than 1/6 of the CCLK of the lpc21xx, otherwise the timing is
screwed. See the ARM manual for detailed information - it even contains
some schematics on how the RTCK is generated in the processor.
Regards,
Rob
Tom Walsh wrote:
>Soentgerath, Guido wrote: >
>>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!
>>
>>
>>
>>
>RTCK is an optional JTAG signal. According to the Abatron BDI2000 manual:
>
>"Adaptive clocking is a feature which ensures that the BDI2000 never
>loses synchronization wih the target device, whatever the target clock
>speed is. To achive this, BDI2000 uses two signals TCK and RTCK. When
>adaptive clocking is selected, BDI2000 issues a TCK signal and waits for
>the Returned TCK (RTCK) to come back. BDI2000 does not progress to the
>next TCK until RTCK is received." >TomW >
