Hi,
I'm having issues connecting to a SCR1 core using a brand new J_link pod (hardware V10.1) which I specifically purchases for this task.
I'm running the lastest beta J-link softwae (v6.45a) as it claims to provide support for the SCR1.
I'm aware of the 1/12 SCR1 clock constraint and the jtag frequency is set to a sufficiently low clock speed (100kHz).

This is the output of the connection attempt:


Connecting to target via JTAG
ConfigTargetSettings() start
ConfigTargetSettings() end
TotalIRLen = 4, IRPrint = 0x01
JTAG chain detection found 1 devices:
#0 Id: 0xDEB01001, IRLen: 04, Unknown device
ConfigTargetSettings() start
ConfigTargetSettings() end
TotalIRLen = 4, IRPrint = 0x01
JTAG chain detection found 1 devices:
#0 Id: 0xDEB01001, IRLen: 04, Unknown device

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

I have no problem connecting to the SCR1 using an Olimex JTAG pod and openOCD. Only the J-link connection doesn't work.
Does anybody have any idea of what could be the problem?

Thank you

I've taken up this issue with Syntacore and according to them J-Link is NOT compatible with SCR1 (as of March 2019).
The only supported option is to use OpenOCD.

Thank you for your reply.
I've seen the segger wiki post regarding the SCR1. I also downloaded the SCR1/Arty SDK and tried to use it with the Segger studio. It doesn't work. What does this error message mean?

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

Obviously j-link is able to communicate and identify the device. So something deeper down must be not as expected.

Anyways. Syntacore apparently is working on the issue and they promised me early access to a fix. We'll see...

The new version of SCR1 is now online. It claims to support the debug spec version 0.13.
Unfortunately the problem persists. J-link cannot connect to the SCR1 with the error message

CPU-TAP not found.

Connection with cheap Olimex OpenOCD works without a problem.

Did ANYBODY ever tried this with j-link and gotten it to work?

Hi Nino,

CAREFUL. The latest update (March 2019) of their SCR1 core changed the ID to DEB11001. DEB01001 is the previous ID they used before that.
Also note that the IR length changed from 4 to 5 in the latest release.

See below for an excerpt of the j-link connect.
Cheers
Daniel

Device "RISC-V" selected.
Connecting to target via JTAG
ConfigTargetSettings() start
ConfigTargetSettings() end
TotalIRLen = 5, IRPrint = 0x01
JTAG chain detection found 1 devices:
#0 Id: 0xDEB11001, IRLen: 05, Unknown device

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

With the latest version SCR1 together with the v6.44e of the j-link software the communication works.