Thank you all for your answers! I haven=B4t played for a while with PIC=B4s and I happen to have a=20 Wisp628 (wich I bought last year, assambled but have not ever used!) and=20 a few 16LF648A. I know it is a low voltage version of the 16F648A. I=20 just wanted to have a known working "blink-a-led" program (and assembler=20 source code) to test my hardware and to "refresh" my mind. The part that=20 is getting me confused is the /MCLR pin and the possible gotchas when=20 programming the PIC. Thank you all for your time! Regards, *Carlos Marcano* -Guri, Venezuela- --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist