SEGGER Forum

Hi

My J-Link can't connect to my target board which is Digi Connect ME (NS7520) development board.
The following are the erroro message copied from J-Link GDB-Server log window.

***** error message ******
ERROR: Could not find supported CPU core on JTAG chain
ERROR: Could not connect to target.

J-Link connected
Firmware: J-Link compiled Jun 28 2007 10:45:08 ARM Rev.5

Resetting target and trying again to connect...
ERROR: Bad JTAG communication: Write to IR: Expected 0x1, got 0x7 (TAP Command : 2) @ Off 0x5.

ERROR: Could not connect to target.

J-Link connected
Firmware: J-Link compiled Jun 28 2007 10:45:08 ARM Rev.5

Resetting target using BP@0 and trying again to connect...
ERROR: Could not find supported CPU core on JTAG chain
ERROR: Could not connect to target.
****** end of error message *****


It also pops a window up and says "TCK (pin 9) low, but should be high. Please check target hardware."

I am sure my target board is OK. Don't know why the J-Link doesn't connect to my board.
Could anybody help !!

Quoted from "SEGGER - Alex"

...Do you have a standard JTAG 14-pin adapter...

Hi Alex

Yes, I do have JTAG 14-pin adapter. But I did not use it. I used the 20-pin cable since the original Digi connect ME board had only a 20-pin JTag socket.
Actually, my J-Link was working fine for the past week. Somehow it just did not work today

Is there anything I can do to examine my J-Link for further information?

Regard,
Henry

Quoted from "SEGGER - Alex"

did you change something since the last time J-Link GDB Server worked?

Software setting, No.
Haredware setting, Yes, unplug JTAG, and couple hours later re-plug in JTAG on the Digi board with no power supplied.

Quoted from "SEGGER - Alex"

Did the J-Link GDB Server stop working after a software update?

No. No update. The GDB server stop working after I re-plug in JTAG on the Digi board.

Quoted from "SEGGER - Alex"

which software version do you use now?

J-Link ARM V3.74j

Also tried v383a, no luck

Quoted from "SEGGER - Alex"

Does J-Link.exe connect to the target?

Not now. It was ok
The following is the message from J-Link.exe

// ----------- J-Link message --------
SEGGER J-Link Commander V3.74j ('?' for help)
Compiled Oct 30 2007 19:51:32
DLL version V3.74j, compiled Oct 30 2007 19:51:29
Firmware: J-Link compiled Mar 3 2008 19:52:16 ARM Rev.5
Hardware: V5.30
S/N : 30001077
OEM : DIGI-LINK
Feature(s) : GDB
VTarget = 3.254V

Error: TRST (pin 3) low, but should be high. Please check target hardware.
JTAG speed: 30 kHz

****** Error: Could not find supported CPU core on JTAG chain
Trying to connect with 5 kHz !


****** Error: Could not find supported CPU core on JTAG chain
J-Link>
// ----------- End of J-Link message --------