When I proved the J1 pins and VCC, I noticed that VCC is electrically connected to the "ARM" pin among the 3 pins in the J1 jumper of the ULINK2. When I set the jumper to 3.3V, VCC doesn't actually get any voltage. Is this the expected behavior? What is the relation between the J1 jumper and the VCC pin?
I think this is a more generic question / I don't think there's necessarily anything wrong with my ULink2 regarding this aspect.
Could someone with a functioning ULINK2 probe the VCC pin when the jumper is set to 3.3V vs ARM and let me know what they get? Thanks!
ULINK2 Jumper information: http://www.keil.com/support/man/docs/ulink2/ulink2_hw_jumpers.htm www.keil.com/.../ulink2_hw_schematic.htm
>When I set the jumper to 3.3V, VCC doesn't actually get any voltage. Is this the expected behavior? Yes.
>Could someone with a functioning ULINK2 probe the VCC pin when the jumper is set to 3.3V vs ARM and let me know what they get?
Position ARM: Target provides power and defines voltage levels for JTAG/SWD interface via VCC pin (debug connector).
Position 3.3V: Internal 3.3V is used to power and define voltage levels for JTAG/SWD interface. VCC pin has no connection to the debugger.