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?
Hi Inge
please check atatched file and i.MX6 System Development User’s Guide
(as it has similar jtag module)
http://cache.freescale.com/files/32bit/doc/user_guide/IMX6DQ6SDLHDG.pdf
Best regards
igor
Hi Igor,
Thank you for your reply. I not quite sure how this could help me. I found that the i.MX6 has a JTAG_MOD pin, to change the JTAG mode, but that pin is not present on the vybrid as far as I can see. I didn't understand how the conversation about gdb server can help me either. Can you explain a little more what you meant?
Best Regards
inge
JTAG_SMODE are '00' and SEC_CONFIG is '0', that means that i am in SCC JTAG mode with no security. So that doesn't seams to be the problem. I tried with gdb server as well, but got the same response:
./JLinkGDBServerCL
SEGGER J-Link GDB Server V6.12g Command Line VersionJLinkARM.dll V6.12g (DLL compiled Jan 27 2017 18:18:51)
-----GDB Server start settings-----
GDBInit file: none
GDB Server Listening port: 2331
SWO raw output listening port: 2332
Terminal I/O port: 2333
Accept remote connection: localhost only
Generate logfile: off
Verify download: off
Init regs on start: off
Silent mode: off
Single run mode: off
Target connection timeout: 0 ms
------J-Link related settings------
J-Link Host interface: USB
J-Link script: none
J-Link settings file: none
------Target related settings------
Target device: unspecified
Target interface: JTAG
Target interface speed: 1000kHz
Target endian: littleConnecting to J-Link...
J-Link is connected.
Firmware: J-Link V9 compiled Dec 16 2016 15:34:10
Hardware: V9.30
S/N: 609301489
Feature(s): RDI, FlashBP, FlashDL, JFlash, GDB
Checking target voltage...
Target voltage: 3.34 V
Listening on TCP/IP port 2331
Connecting to target...ERROR: CPU-TAP not found in JTAG chainERROR: Could not connect to target.
Target connection failed. GDBServer will be closed...Restoring target state and closing J-Link connection...
Shutting down...
Could not connect to target.
Please check power, connection and settings.
Do you have any more ideas?
Best regards
Inge