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IN CASE OF TROUBLE:
SYSTEM CRASHES/HANGS WHEN SLOT POWER TURNED ON
Some PCIe or PCI boards do not come up with all of their PCIe bus lines inactive, as is required by the
specification. These boards may not work on live insertion extenders. The PCIeEXT-16-HOT holds
RESET to the UUT low until at least 500ms has transpired since all power supply voltages have risen
to their full specified values. Then, the PCIe-EXT16-HOT removes the RESET# signal to the UUT.
This allows correctly designed PCIe bus boards to operate properly on power-up on our live insertion
extender.
If the system hangs or crashes when the slot power switch is turned on, the board-under-test may be
driving the bus immediately after its power is brought up (while RESET# is still asserted) which is
illegal. One way to remedy the problem is to modify the board-under test.
SYSTEM RESETS WHEN SLOT POWER SWITCH IS TURNED ON
The power supplies in some systems have inadequate reserve capacity to handle the inrush current of
some boards-under-test when they are switched on in an active extender. This may cause the
system’s +12V or +3.3V supplies to dip, causing the system to reset. This problem is rare, as the
PCIeEXT-16-HOT and PCIEXT-64U / UB have slew-rate limiting circuitry, causing the supplies to the
UUT to rise smoothly over a 200 us period, reducing inrush current. If you suspect this problem is
occurring, try the PCIeEXT-16-HOT in a different system.
SYSTEM HANGS AFTER REINSTATING CONFIGURATION SPACE
Some UUTs use CPLDs or FPGAs that fail to initialize correctly due to the controlled slew power
ramping on the PCIeEXT-16-HOT.
UUT IS NON-RESPONSIVE AFTER REINSTATING CONFIGURATION SPACE
Some PCI/PCIe devices have registers outside the configuration space that must be setup by the
device's corresponding device driver before the device can be accessed by user software. These
devices require the device driver to be reloaded after the configuration space is re-instated.
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