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?
Did you mean to post in this thread: http://www.keil.com/forum/62609 ?
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.