Blinky On Link 2 was working - now not

Discussion created by lpcware Employee on Jun 15, 2016
Latest reply on Jun 15, 2016 by lpcware
Content originally posted in LPCWare by krk@GoTas.com on Sat Feb 15 13:40:14 MST 2014
Have two Link 2 boards.
First board - connected via USB to PC, has jumper J2 installed to power 2nd board.
First board (dbgr probe) J7 is connected to 2nd board ( target) J2. (is this correct connection - I believe Blinky worked in this config yesterday - but now not working).

Symptoms of problem:

Initially - Dbg (1st) board will enumerate in Device manager (W7)  as LpcDevice:Lpc Based USB device
LED will be lit on 1st board.

Connect 2nd (tgt) board: LED lights (powered by J2 on dbg probe board) - good
Dbg probe board still enumerated as LPC device - good

Press "Debug Blinky" on "LPC4370_Blinky" on Quickstart Panel...
enumeration of debugger probe "goes away"
LED on Debug Probe board turns off
Xpresso indicates "No Device Selected" in JTAG Configuration dialogue (It apparenly gets past the "Initializing Red-Link" Server with LPC43....... (file)" stage

Thoughts as to source of problem?
What steps to confirm major location of problem?
What could cause enumeration to go away (and become an additional "HID compliant Device" that was not there before)?

see screenshots in attached file

Thank you for assistance...