Honored ContributorHi, I am developing a board to work with the HSMC connector and will require 26 LVDS differential receive pairs. There are only 17 RX pairs and 17 TX pairs. Can the TX pairs be used as inputs so that i can have 34 RX differential pairs? I dont see any mention of the ports being dedicated TX or RX channels. Does anyone know of a workout to get more RX LVDS lines on this board? thanks!!
Honored ContributorDid you read the specification?
http://www.altera.com/literature/ds/hsmc_spec.pdf When operated in LVDS mode, the signals are unidirectional, and hence the naming convention. If you are making a custom system where you do not need to interface to any other HSMC boards, then you could re-define the HSMC LVDS TX lanes to be RX. However, if your system is custom, then just select a more appropriate connector solution. HSMC is not an industry "standard". You might want to consider using FMC. FMC was a Xilinx idea, but at least its now a VITA standard (VITA 57). http://www.vita.com/fmc "FMC HPC connector provides connectivity for 160 single-ended or 80 differential user-defined signals" The Arria V Development Kit has an FMC connector http://www.altera.com/products/devkits/altera/kit-arria-v-gx.html Cheers, DaveHonored ContributorThanks Dave!
When i went over the HSMC specs document I understood it was more general and not board specific. Unfortunately the board and HSMC connector has already been chosen so I was trying to get it to work with a custom system. But if its true the HSMC LVDS TX differential lanes can be redefined so that i can use all 34 differential pairs as RX, then that will be perfect. I will definitely consider using FMC in the next project.Honored Contributor
