SYSTEM POWER UP
4-2
600-2705 PCI Express Expansion System User’s Manual
Revision 1.0, February 2008
4.3.2
De-Emphasis
The transceiver silcon used on the PCIe-409 has four steps of programmable de-emphasis; 0dB, -3dB, -
6dB and -9dB. Cyclone Microsystems has determined that 0dB is the correct setting for both 1m and 3m
PCIe cables shipped with Cyclone PCIe Expansion Systems. The PCIe-409 has a DIP switch that is
factory set for 0dB de-emphasis but permits a user to reselect to any of the four possible settings. Users
should not change the de-emphasis setting unless they have the proper test equipment to verify their
results. Nomenclature on the PCIe-409 shows show how to set the DIP switch for all four de-emphasis
steps. Users change de-emphasis at their own peril.
4.4
LINK INDICATION - LED DEFINITION PCIE-414
The PCIe-414 has eight surface mount LEDs located on the top side of the PCB see Figure 5-1. There is
one LED for each slot and one LED for the cable link. The LEDs are labeled SLOT A through SLOT G
and UP PORT. The UP PORT LED corresponds to the cable link to the PCIe-409. If the LED is on, the
Physical Layer of the link for the associated port has trained to at least x1 width.
The two LEDs that are seen through the back panel next to the PCI Express connector, CR1 and CR2,
also indicate that at least a x1 link between the PCIe-414 and the PCIe-409 has trained at least x1. CR1
and CR2 have identical functions.
