If you're going to try and program it while linked directly (thru Hyper Terminal) you're gonna have a hell of a time if it's more than a little bit! Using Commissioning Tools (Siemens Program) is the only way to do it, or if you've got a PC on site with Insight, you can purchase (or may already have) the Program Editor application. These have an assist option that covers pretty much what's in the Manual, and will compile the code to check for errors. Programming thru Hyper Terminal won't tell you if you've made a mistake, and you've gotta type the whole line in, letter perfect each time pretty much. Post what you're trying to figure out/modify and I can help you, unless you're just looking to learn more in general? The manual is long, containg alot of 'unneccesary' stuff, and doesn't tell you a few quite common 'problems'. If you still want it, someone else posted it in here at http://home.comcast.net/~fredrock/mvc/Siemens_ppcl.pdf
Hope this helps, cos the hardest part is experience in this damn language!