Carried out some further work on failed mezzanine modules.

Inspected them externally and removed the copper block, internally with a bench microscope.

Found two obvious faults ..... broken components with scrambled pcb tracks.

To help determine problems with loading control registers I've added a new menu item in the ASIC control window to allow all four ASIC return values to be checked. This is only useful at the mezzanine test system.

Tested 7 that were labelled as faulty. Failed all of them. 2 with broken components and 1 with some broken bond wires. 

Tested one fresh from the cupboard. It failed with over current on the +5v psu ( > 4A! ).

I propose to create a method of testing these mezzanines which allows better access to the power supply regulators ( LT3080 ) and the associated control voltage.