We are trying to establish a 4 lane Aurora Communication channel between 2 Virtex5 LX220T devices over RocketIOs. We have observed that the Channel between these two channel partners is lost intermittently i.e the Channel-Up signal keeps toggling. This loss of channel is accompanied with Soft_err and Hard_err signals.
Experimental Setup #1:
-> 2 Virtex5 LX220T FPGAs on a single board (board#1), each device connected to the back plane through RocketIOs. The interconnection between the RIOs coming out of the back plane is done by using a cable.
XST version 12.4 and Aurora_8b/10b version 6.1 is used.
We have tried all the combination of RXEQPOLE and RXEQMIX values on the GTP tiles, with TXPREEMPHASIS value equal to b111. However, we are losing the channel in all the cases.
Experimental Setup #2:
On the same back plane, but with another board(board#2) which has a single Virtex5 FX100T device, we tried to instantiate two 4 lane Aurora_8b/10b endpoints. These 2 Aurora endpoints are connected to the same RIO slots on the back plane. And same cable was used to interconnect the RIOs on back plane.
XST version 11.1 and Aurora_8b/10b version 4.1 is used.
With no change in default values of TXPREEMPHASIS, RXEQPOLE and RXEQMIX the channel came up without any errors and is consistent.
what might be the reasons for the loss of channel with board#1? How do we solve it?
