RS232 find the right configuration

[bigdogguru]

Here is a standard 14-pin JTAG pinout, try and trace the connections to see if the 14-pin connector is indeed a JTAG connection:




If the unit boots Linux, can you get a root prompt or open a terminal window if it is a GUI environment? If so, we can query the OS and obtain info concerning the units processor.


BigDog

 

[priestnot]

Thanks fo the image.
That is the thing i connected the PC RS232 to the micro using the max232, to get to the console. But since i do not know the baudrate I cannot.
I will try to contact the manufacture (I do not think they will tell me), and ask what is the processor, and what is the serial port configuration to get in the console.

 

[bigdogguru]

I was referring to accessing the console via the keyboard, video and mouse (KVM) connections, not via the possible serial port.

When you boot the system with the KVM attached, it should provide access to the OS and if it is Linux, possibly root access.

BigDog

 

[priestnot]

I will try to do that tomorrow.
If it does not show the information what more can be done?

 

[bigdogguru]

If the connector pad is indeed a JTAG connection, then the JTAG TAG ID can be used to identify an ARM variant.

Also register 0 of the ARM device's System Control Coprocessor is hardwired with information such as the core’s part number, revision number, architecture version, implementation variants, and who implemented the core.

BigDog

 

[priestnot]

Ok I am a linux user I dont even have a windows computer :s
I searched abit and i did not find a ("well known" "every one uses") Jtag software and cable! Do you know any software so i can get the register 0 info?

 

[priestnot]

Ok i got news (Not good ones I am afraid)

When i connect a monitor keyboard and mouse it just shows the application for the thinclient.

So I must go to the second option to the JTAG processor ID register.

I found OpenOCD, but i did not find any instruction how to make a cable for it. Is the a cable based on RS232 or parallel port that i can build? Or i must buy one? Is tehre a cheep one that i can buy?

 

[bigdogguru]

When i connect a monitor keyboard and mouse it just shows the application for the thinclient.

What OS is the application running within, Windows CE or Linux? Was there any boot info displayed while the device was booting? Usually there is a way exit the application and access the embedded OS both in Windows CE and Linux.

So I must go to the second option to the JTAG processor ID register.

I found OpenOCD, but i did not find any instruction how to make a cable for it. Is the a cable based on RS232 or parallel port that i can build? Or i must buy one? Is tehre a cheep one that i can buy?

First you must determine whether the connector pad is indeed a JTAG connection. Otherwise you could damage either the thinclient, JTAG programmer/debugger or both.


I use both Segger's J-Link and KEIL's ULINK2, there are less expensive ARM-JTAG devices, although I have no experience with them.

Segger does offer a noncommercial J-Link which is the same unit sold to commercial customers:

Segger's J-LINK EDU


Olimex sells several ARM-JTAG units, which vary in price and features:

ARM-JTAG DONGLES

I unfortunately have no experience with Olimex JTAG devices.

BigDog