Hi Glendon, Is your shift register a HC595? Do you you have a link to your website? Thomas Glendon Turner wrote: Hi Thomas, I have developed a 20 Character 7x5 dot matrix display (yes 700 leds) that runs from an F876 (or C63!). I have the 5 columns driven with Darlington transistors, and use shift registers for the rows. This is a total of 7 pic pins, or 8 if you use a shift register with a latch. My display routine gets any serial data during the on-time, and has plenty of time to decode this in my character generator routing. The data is rs232 at 9600 baud, and I have dozens of these installed in industrial premises here in oz with no failures to date, and they have been running now for 4 years. One more note, use the daylight viewable led displays for better viewing in all conditions. Regards Glendon -----Original Message----- From: pic microcontroller discussion list [mailto:PICLIST@MITVMA.MIT.EDU] On Behalf Of Thomas N Sent: Thursday, 12 June 2003 11:03 AM To: PICLIST@MITVMA.MIT.EDU Subject: [PIC]: Driving LED Matrix Display from a PIC Hi everyone, With 32 I/O from the 16F877, I think I can control a 16x16 LED matrix display. Because of the limited current coming out from the I/O, I don't think a PIC can drive the LEDs directly. Is there a driver IC or something to drive the LEDs? Is there a better way to do this? Thank you in advance! Thomas --------------------------------- Do you Yahoo!? The New Yahoo! Search - Faster. Easier. Bingo. -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads -- http://www.piclist.com hint: The list server can filter out subtopics (like ads or off topics) for you. See http://www.piclist.com/#topics --------------------------------- Do you Yahoo!? The New Yahoo! Search - Faster. Easier. Bingo. -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.