[linux-audio-user] PD question - serial control?

hi - this is really a PD list question, but I thought it might be smart to crosspost...sorry for any inconveinance... I am currently, among other things (one step at a time), trying to figure out how to control PD via the serial port. that is the question of the hour. just want to use hyperterminal to send a word, like "hello", and have pd do something based on that word, like print hello or something. for background, the project (due tommorrow, handed to me last night) is: a button box has 6 buttons: five record and one play. when a child who is standing between a green screen and a camera (connected to s-video input of a capture card) hits, say, record 1, a chip inside sends the text "record1" to a serial output. on the other end, a computer running max/jitter or pd/gem (probably the former) plays back a set video file (a different one if it's "record2"), placing it in the fill of a chroma key, and records the composite of the camera and the fill for 20 seconds, while the kid dances around in front of the background. if the kid pushes the play button, the last combined video is played back via the s-video output of the regular video card. i don't even have max yet cuz they haven't sent the serial number. so all I want to do this minute is send the word "play" to PD via the serial port and have it do something, anything, even just say hello. i'm very new to PD though. I can get it to, for example, print hello in its terminal. but so far documentation i read makes me think that the "serial" object only outputs to the serial port as opposed to reading from it and parsing what it's getting...