If other timing critical routines are present, the program cannot >spend too much time going through strings of characters. On the other hand, >a certain degree of integrity must be maintained. Can the interrupt routine just receive stuff to a buffer and have the "main loop" evaluate the stuff? Harold Harold Hallikainen harold@hallikainen.com Hallikainen & Friends, Inc. See the FCC Rules at http://hallikainen.com/FccRules and comments filed in LPFM proceeding at http://hallikainen.com/lpfm ___________________________________________________________________ You don't need to buy Internet access to use free Internet e-mail. Get completely free e-mail from Juno at http://www.juno.com or call Juno at (800) 654-JUNO [654-5866]