Try MAX1608 (Serial to parallel and parallel to serial). Bala Chandar cc: Sent by: pic Subject: Re: [EE]: Which is the ideal IC? microcontroller discussion list 11/12/01 00:11 Please respond to pic microcontroller discussion list In my circuit, I am using all the 8 pins of Port B and pin 6 of Port A as inputs to detect the closing of 9 PB switches. The PIC used is 16F628 with internal RC Oscillator. Port B weak pull-up is enabled and PortA.6 has a 4.7K pull-up resistor. As I am running short of I/O pins, I want to use an IC to reduce the number of pins used by the PIC for detecting key pressings. After a search through CMOS data book, I found 74HC147 (10 to 4 Priority Encoder) almost ideal for the purpose. With this IC, I will need only 4 pins of the PIC and as many as 5 pins will become available. Now, my question: Is there a better IC for the purpose? Please let me know if there is. Thanks & Regards, Bala -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details. -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.