Error: CPU-TAP not found in JTAG chain

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  • Error: CPU-TAP not found in JTAG chain

    Could you tell me what I am doing wrong, or what flaws I should look for? I read other threads where users were asked for IDCODE info, I copied those commands but got 0. Is that my problem (assuming I ran the commands correctly)?

    I have connected the J-link to a 20-pin ARM JTAG to 20-pin TI JTAG adapter, then to the target. The cables are a total of about 1 foot long, but I tried 1 khz. The EMU0 and EMU1 pins are floating on the TI adapter.

    Thanks

    ===============================================================


    SEGGER J-Link Commander V5.12e (Compiled Apr 29 2016 15:04:36)
    DLL version V5.12e, compiled Apr 29 2016 15:03:58

    Connecting to J-Link via USB...O.K.
    Firmware: J-Link V9 compiled Mar 29 2016 18:46:37
    Hardware version: V9.30
    S/N: 269303908
    License(s): FlashBP, GDB
    OEM: SEGGER-EDU
    VTref = 3.283V


    Type "connect" to establish a target connection, '?' for help
    J-Link>connect
    Please specify device / core. <Default>: ARM11
    Type '?' for selection dialog
    Device>
    Please specify target interface:
    J) JTAG (Default)
    TIF>
    Device position in JTAG chain (IRPre,DRPre) <Default>: -1,-1 => Auto-detect
    JTAGConf>
    Specify target interface speed [kHz]. <Default>: 4000 kHz
    Speed>1 khz
    Device "ARM11" selected.


    TotalIRLen = 12, IRPrint = 0x0AD1
    TotalIRLen = 12, IRPrint = 0x0AD1

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

    TotalIRLen = 12, IRPrint = 0x0AD1
    TotalIRLen = 12, IRPrint = 0x0AD1

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

    Can not connect to target.
    J-Link>wjc 6
    Command 0x6 (Unknown JTAG instruction) successfully written
    J-Link>wjd 0,36
    returns 0x0
    J-Link>wjc e
    Command 0xE (IDCODE) successfully written
    J-Link>wjd 0,36
    returns 0x0
    J-Link>

  • Hi,

    What target device do you have in your setup?
    Do you use custom hardware or an evaluation board?
    According to the output, you are using an older version of the J-Link software (V5.12e). Do you see similar behavior when using the latest version from our website (V6.12a)?
    segger.com/jlink-software.html


    Best regards
    Erik
    Please read the forum rules before posting.

    Keep in mind, this is *not* a support forum.
    Our engineers will try to answer your questions between their projects if possible but this can be delayed by longer periods of time.
    Should you be entitled to support you can contact us via our support system: segger.com/ticket/
    Or you can contact us via e-mail.

  • I am targeting a custom Asic from TI in a production board. It has been end-of-lifed and there is no support or documentation.

    I believe it is ARM11. (It could also be ARM Cortex-M0, ARM Cortex-M0+, ARM Cortex-M1, SecurCore SC000)


    I will try the newer J-link software tonight, thank you.

  • No change with new software:


    SEGGER J-Link Commander V6.12a (Compiled Dec 2 2016 16:44:55)
    DLL version V6.12a, compiled Dec 2 2016 16:44:26

    Connecting to J-Link via USB...O.K.
    Firmware: J-Link V9 compiled Dec 2 2016 15:35:20
    Hardware version: V9.30
    S/N: 269303908
    License(s): FlashBP, GDB
    OEM: SEGGER-EDU
    VTref = 3.285V


    Type "connect" to establish a target connection, '?' for help
    J-Link>connect
    Please specify device / core. <Default>: ARM11
    Type '?' for selection dialog
    Device>
    Please specify target interface:
    J) JTAG (Default)
    TIF>
    Device position in JTAG chain (IRPre,DRPre) <Default>: -1,-1 => Auto-detect
    JTAGConf>
    Specify target interface speed [kHz]. <Default>: 4000 kHz
    Speed>5khz
    Device "ARM11" selected.


    TotalIRLen = 12, IRPrint = 0x0AD1
    TotalIRLen = 12, IRPrint = 0x0AD1

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

    TotalIRLen = 12, IRPrint = 0x0AD1
    TotalIRLen = 12, IRPrint = 0x0AD1

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

    Cannot connect to target.
    J-Link>

    The post was edited 1 time, last by skintigh ().

  • I believe it is ARM11. (It could also be ARM Cortex-M0, ARM Cortex-M0+, ARM Cortex-M1, SecurCore SC000)
    Without having this information, i do not really wonder that the connect fails because you have to at least select the correct core.


    Best regards
    Erik
    Please read the forum rules before posting.

    Keep in mind, this is *not* a support forum.
    Our engineers will try to answer your questions between their projects if possible but this can be delayed by longer periods of time.
    Should you be entitled to support you can contact us via our support system: segger.com/ticket/
    Or you can contact us via e-mail.

  • Quick followup:
    Is it possible that you want to send simple JTAG sequences? If yes, you do not have to perform the "connect" in J-Link Commander. Especially if you do not have any information about your device. You can send the required JTAG sequences using the "wjraw" command which is available before "connect". Apart from this, we would recommend to rather use a J-Link script file to output JTAG sequences as they allow a more c like syntax.

    Best regards
    Erik
    Please read the forum rules before posting.

    Keep in mind, this is *not* a support forum.
    Our engineers will try to answer your questions between their projects if possible but this can be delayed by longer periods of time.
    Should you be entitled to support you can contact us via our support system: segger.com/ticket/
    Or you can contact us via e-mail.

  • I have tried all 5 possible ARMv6 cores. Same results.

    I don't know anything about wjraw, do you have a guide or specific commands I should try?


    My primary goals are to dump the flash and memory. Using GDB would be also great. Anything you can tell me to go in that direction would be great.


    Thanks.