Question regarding jlink.exec_command()

[TheColector]

Hi,
I have a following question.

Question

Does anyone know what might cause execution of certain command to throw exception when called via jlink.exec_command()?

pylink/pylink/jlink.py

Line 946 in a2172aa

def exec_command(self, cmd):

Context

I'll dig deeper into it tomorrow, but for now I've observed that commands such as Regs, Go or Mem end up throwing exception.
Note: I call the above ones only after jlink.open() and jlink.connect() were called (doesn't matter whether target was halted beforehand or not)

Calling Halt seem to work fine though. Other configuration like commands that get executed before connecting to target work correctly (like JLinkDevicesXMLPath).

Source of confusion

Here, I'm a bit at a loss, because JLink SDK Guide states the following:

• JLINKARM_ExecCommand() from the JLINK DLL offers a possibility to execute several command strings.
• "For a detailed description of all available commands strings please refer to the J-Link User Manual (UM08001)"

Initially I thought that all of the commands from jlink commander were supposed to be working via jlink.exec_command(), but then I realized those are not COMMAND STRINGS that you should pass to the aforementioned DLL.
Command strings are defined here.
But that does not explain why Halt works and Go does not (both come from JLink Commander set of commands).

I searched forums and web looking for answer but didn't find any.

BR,
Michael

[hkpeprah]

Am exception is thrown when the command populates an error string indicating that the command failed: https://github.com/square/pylink/blob/master/pylink/jlink.py#L971. The string should indicate why the command failed, though they may not be super helpful in some instances.

[TheColector]

Am exception is thrown when the command populates an error string indicating that the command failed: https://github.com/square/pylink/blob/master/pylink/jlink.py#L971. The string should indicate why the command failed, though they may not be super helpful in some instances.

Yeah, I checked for the string but no help from that one.
I have a feeling that exec_commands is able to execute COMMAND STRINGS only*.

*-aside from the fact that it can execute halt as well which belongs to a different set of commands which is surprising.

This seems like a question fit for Segger's forum rather than here. I'll try asking there and share their reply here once they provide it.

Thanks