Hi, I'm currently designing a board with fpga(U1) and a chip(U2) where IO are in levels SSTL2. Both chip are BGA 1mm and 0.8mm. 8 IO one-way U1 to U2, and 8 one-way U2 to U1. So 16 lines point to point. Clock frequency is 250MHz in single data rate. The two chips are very close, less than 1/2 inch. I made schematics with Rs and Rt, but they takes a lot of place, even is I use fpga integrated Rs. I think this could be possible to connect these 2 chips without RS and RT, but I dont have a simulator for my PCB router, and so, to validate this solution. I found some papers and discussions were RT is not used, other paper were RS is not used. Did you try this idea or did you think this idea can works with good reliability ?? Regards, Bernard -- Bernard Esteban Electronic Design Engineer MAF Agrobotic 546 rue Gustave Jay BP112 82001 Montauban Cedex France Tel +33(0)563632770 Fax +33(0)563203459 Fax alternate +33(0)563630785 Email: esteban.bernard@xxxxxxxxxx Email alternate: maf@xxxxxxxxxxxxxx site web: http://www.maf-roda.com ====================================== This message contains information, which maybe confidential and privileged. Unless you are the addressee (or authorize to receive for the addressee) , you may not use, copy or disclose to anyone the message or any information contained in the message. If you have received the message in error, please advise the sender by reply to bernard.esteban.maf@xxxxxxxxxx and delete the message. Thanks. ====================================== ------------------------------------------------------------------ To unsubscribe from si-list: si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field or to administer your membership from a web page, go to: //www.freelists.org/webpage/si-list For help: si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field List FAQ wiki page is located at: http://si-list.org/wiki/wiki.pl?Si-List_FAQ List technical documents are available at: http://www.si-list.org List archives are viewable at: //www.freelists.org/archives/si-list or at our remote archives: http://groups.yahoo.com/group/si-list/messages Old (prior to June 6, 2001) list archives are viewable at: http://www.qsl.net/wb6tpu