AnsweredAssumed Answered

Can't program Vybrid, in JTAG chain

Question asked by Inge Nikolai Torsvik on Feb 2, 2017
Latest reply on Feb 24, 2017 by Inge Nikolai Torsvik

Hi,

 

I have a JTAG chain with a VF6XX_A5 and a FPGA (igloo nano from microsemi). I have previously connected to these two device separately, and I had then no problem programming any of them. I am using SEGGER J-link plus with JLINK Commander to connect to the MCU.

 

The setup I am using is like this:

TDI --> VF6XX_A5 (IRlen 4) --> Igloo nano (IRlen 8) -->
TDO <--------------------------------------------------------------------------

 

JLINK commander setting I am using is
Device: VF6XX_A5,
TIF: JTAG,
JTAGConf: -1,-1 (I have tried 0,0, which should be the correct according my setup, but nothing changed)
Speed 4000 KHz

The respons i get is:
Device "VF6XX_A5" selected.


TotalIRLen = 12, IRPrint = 0x019D
TotalIRLen = 12, IRPrint = 0x019D
TotalIRLen = 12, IRPrint = 0x019D
TotalIRLen = 12, IRPrint = 0x019D

****** Error: CPU-TAP not found in JTAG chain

TotalIRLen = 12, IRPrint = 0x019D
TotalIRLen = 12, IRPrint = 0x019D
TotalIRLen = 12, IRPrint = 0x019D
TotalIRLen = 12, IRPrint = 0x019D

****** Error: CPU-TAP not found in JTAG chain

Can not connect to target.

 

I have contacted support on SEGGER, and I got an feedback saying that I have to switch mode on the vybrid to be able to program it in a chain. I Iooked through the reference manual, and what I found on the topic is this:

 

JTAG to cJTAG change sequence
• Reset the debug port.
• Set the control level to 2 via the zero-bit scans.
• Execute the Store Format (STFMT) command (00011) to set the scan format register 1149.7 scan format.

 

Is it correct that I need to changed the mode to be able to program? How can I "set the control level to 2 via the zero-bit scans"? I am able read out the IDCODE for both devices, and JLINK commander is detecting the correct IR length.

 

Any suggestion is appreciated. Has anyone connected the vybrid in a JTAG chain before?

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