2008/11/6 gardenyu : > I'm building a 3 digit LCD display trying to use a > Microchip's AY0438 controller. What is the reason you want to use such an old controller? I do not know about it. The datasheet is dated 1995. Does Microchip still actively promote this device? Xiaofan -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist