Hi, I tried very different VHDL UART core. (for Xilinx Device) - OpenCores (miniUART) - QuickLogic , http://www.quicklogic.com/images/appnote20.pdf - Xilinx CPLD UART - Digilent UART http://www.digilentinc.com/Resources/VHDL.cfm In my opinion, best of Uart component is digilent uart design. It is based on State machine and easy to read code and it has many explanations. I tried 1MHz speed. It is perfect. It uses only 65 logic cell. Ferhat, *************************************** Ferhat YALDIZ Hardware Design Eng. Information Tech. Inst. - TUBITAK Gebze - Kocaeli TURKIYE *************************************** ------------------------------------------------------------------ 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 technical documents are available at: http://www.si-list.net 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