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Altera_Forum
Honored Contributor
Honored Contributorunable to scan device chain. cann't scan jtag chain
Hi,
I am using Nios II Embedded Evaluation Kit (Cyclone III - EP3C25F324C6NES). Though it is having direct programming capability through the Usb cable. I like to test the Programming through the Jtag (J4) . So, I connected the board with the USB Byte Blaster with the Jtag end to the baord and the USB end to the PC. Now , If I open the Programming tool and press the Autodetect Tab then the following message is being popped up .. "Unable to scan device chain. Cann't scan Jtag chain." Could any one help me, how to ovrcome this error .. Thanks , Srinath.17 Replies
Altera_ForumAlways worth checking the basics first.
Are you sure the Board is powered correctly? Are you sure the USB blaster is connected to the board correctly? (orientation etc) The error message you see is usually a result of an incorrect connection between the Board and USB Blaster Hope this is of some use.- Altera_Forum
Hi,
Thanks for the reply... I checked the power supple as well as the connectivity ..Every thing ok... Even then it is showing the same error .. Could you mention why ??? Thanks, Srinath. - Altera_Forum
Does the blue LED on the USB blaster light up, when you try and scan? and is the JTAG cable connected the right way around?
- Altera_Forum
Yah I observed that the Load LED (Blue) does not glow when I connect the USB Byte Blaster in J4 slot .
But when I connect through the USB cable then it is glowing .... So, what could be the answer now ??? Is that the fault with the USB Byte Blaster ??? -Srinath. - Altera_Forum--- Quote Start --- Yah I observed that the Load LED (Blue) does not glow when I connect the USB Byte Blaster in J4 slot . But when I connect through the USB cable then it is glowing .... So, what could be the answer now ??? Is that the fault with the USB Byte Blaster ??? -Srinath. --- Quote End --- Hi Srinath, I don't know your Evaluation board very well, but as I remember from other board it could be that there are additional IC's in the Jtag Chain, like a Flash or MAX device. Is there a chapter in your board documentation how to setup the JTAG chain?
- Altera_Forum
Have you removed JP8, as specified in the reference manual (http://ftp://ftp.altera.com/outgoing/download/support/ip/processors/nios2/niosii_eval_reference_manual_80.zip)?
- Altera_Forum
Hi,
I have the Cyclone III FPGA Starter Board Reference Manula (Dated : - October 2007) I think this is the new manula available. In that manula it was mentioned to add the Jumper to JP8 to work eith JTAG, Even though I added the Jumper even then the same error continues.... Please see below for the specifoed point from the document ... " JP8 : Adding the shunt enables configuration of the Cyclone III device using the JTAG header and an external USB-Blaster. When the shunt is not in place, the embedded USB-Blaster circuitry must be used to configure the Cyclone III device. (The board ships without the JTAG header populated.) " Now what to do ??? Thanks, Srinath. - Altera_Forum--- Quote Start --- Hi, I have the Cyclone III FPGA Starter Board Reference Manula (Dated : - October 2007) I think this is the new manula available. In that manula it was mentioned to add the Jumper to JP8 to work eith JTAG, Even though I added the Jumper even then the same error continues.... Please see below for the specifoed point from the document ... " JP8 : Adding the shunt enables configuration of the Cyclone III device using the JTAG header and an external USB-Blaster. When the shunt is not in place, the embedded USB-Blaster circuitry must be used to configure the Cyclone III device. (The board ships without the JTAG header populated.) " Now what to do ??? Thanks, Srinath. --- Quote End --- Did you try the embedded USB-Blaster ? In my understanding you have only to connect your PC with the USB port on the board. Is that working ? At least this should work, because this is according to the manual the default board configuration.
- Altera_Forum
Hi,
I already programmed with the default USB ... There is no issue with the default USB .. But I am trying to work out with the JTAG as well.. So, pelase let me know how to work with the JTAG... Thanks , Srinath. - Altera_Forum--- Quote Start --- Hi, I already programmed with the default USB ... There is no issue with the default USB .. But I am trying to work out with the JTAG as well.. So, pelase let me know how to work with the JTAG... Thanks , Srinath. --- Quote End --- Hi Srinth, I found in the manual ( Version June 2008) JP8 Removing the shunt enables configuration of the Cyclone III device using the JTAG header and an external USB-Blaster. When the shunt is in place, the embedded USB-Blaster circuitry must be used to configure the Cyclone III device. (The board ships without the JTAG header populated.)
