Thank you everyone who reply to this Email. I need read/write access to RAM very quickly. The PIC will receive about 800 bytes of data from the "master" every 16.6ms (60Hz). Within this 16.6ms, the PIC will also have to manipulate the data and send to 6 LED drivers. Yes, I am doing a LED panel (16x48). Regards, Thomas Jan-Erik_Svderholm_XA_(TN/PAC) wrote: How fast (reads and/or writes per second) How many read/writes per day, week, year ? Ramtron FRAM could be one choice. Do you realy have the I/O pins free to both drive a 12-13 bit address and a 8 bit data bus on the 16F877 ? Or you could use a couple of S-in P-out shift registers to clock out the address using 2-3 pins and another pair of shift registers to read/write the databus. Another way could be to use one of the PICs with larger internal RAM, see the 18F6xxx and 18F8xxx lines. Up to 3820 bytes of RAM. Jan-Erik. -----Original Message----- From: Thomas N [mailto:thomasn102@YAHOO.COM] Sent: den 19 juli 2003 19:55 To: PICLIST@MITVMA.MIT.EDU Subject: [PIC]: External RAM Hi everyone, I am designing a LED panel and I need few more kilobytes of RAM. Do you have any suggestion on how to add external RAM to the PIC16F877? I think I will need parallel RAM for faster access. REgard, Thomas --------------------------------- Do you Yahoo!? The New Yahoo! Search - Faster. Easier. Bingo. -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listserv@mitvma.mit.edu with SET PICList DIGEST in the body -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listserv@mitvma.mit.edu with SET PICList DIGEST in the body --------------------------------- Do you Yahoo!? The New Yahoo! Search - Faster. Easier. Bingo. -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listserv@mitvma.mit.edu with SET PICList DIGEST in the body