Transfusion Demo: Users' Guide ------------------------------ Transfusion Demo - This is a demonstration version of a New Desk Accessory Terminal program presented in GS+ Magazine. Copyright 1989-90, by EGO Systems. Transfusion Demo was written by Josef Wankerl in ORCA/C. Note: This Transfusion Demo assumes that you have an external modem attached, although this is not necessary. You may, in fact, just be connected straight to another computer or serial device. The Transfusion Demo doesn't care. It sees the internal port as a modem device and can communicate to any such modem device in your system. At this point, this program will not work with internal modems. This demo is a New Desk Accessory (NDA) which takes advantage of the Apple IIGS's internal modem port to allow simple terminal functions along with XModem file transfers. This Transfusion Demo was written with ease of use in mind. If you are familiar with the IIGS desktop environment, you can use the Transfusion Demo. The best way to learn how to use this demo is to fire it up and mess with some of the options. To install it, use ShrinkIt GS to extract the file XFusionDemo from the archive and place it in the *:System:Desk.Accs: folder of your system disk, and then restart your computer. When you do this, the Transfusion Demo will be available from any program that supports New Desk Accessories. Just select the Transfusion Demo menu item from under the Apple Menu. A window will appear while the Transfusion Demo loads the tools it needs, and then you will be presented with a window containing a menu bar and a standard Text Edit control. What Do You Do Next? -------------------- Anything you type, when the Transfusion Demo is the front window, is sent to your GS's internal modem port (and hence to any modem that may be attached). If you want to dial up your favorite BBS, such as our own pro-gsplus at (615) 875-4607, just enter in the command to make your modem dial (such as the Hayes standard ATDT1-615-875-4607). Yes, Transfusion Demo doesn't have a "Dial" menu option (or hang up, for that matter). Why not? Well, because this really isn't supposed to take the place of your favorite communications program. This program assumes you know what you are doing with your modem. Actually, there doesn't have to be a modem connected at all, so dialing wouldn't be a relevant command, although in most cases, a modem will be present. Transfusion Demo is meant for simple terminal facilities. Because of this fact, the Transfusion Demo will be slower than other communication programs you may be familiar with. This is because the Transfusion Demo has to share events with its host application (and because it uses GS/OS calls, not direct calls to the firmware, and it uses Text Edit which really wasn't meant for large volumes of information to pour through it at once). Also, because your application must share events with the Transfusion Demo, you will notice a marked slowdown in response time from it as well. But this is a fair price to pay for a utility of this magnitude. What's On The Menu? ------------------- The Transfusion Demo has a menu bar with four menus: File, Edit, Send, and Receive. The File menu resembles most application's file menu, although some of the items may not do exactly what they do for other programs. The New menu item doesn't create a new window, it takes the text currently in the Transfusion Demo window and throws it away, leaving you with a new, fresh slate. The Close menu item, as you might expect, closes the Transfusion Demo. The Save and Save As options allow you to save the text that is currently in the Transfusion Demo window. The Info menu item displays information about the text in the Transfusion Demo window, the modem device, and the current save file's name. The About menu item displays the usual information for an about item. The Edit menu contains the standard Copy and Paste items, but not the Undo, Cut, or Clear options. This is because Copy and Paste make sense for a modem device, but the others do not. You can select text in the Transfusion Demo window and Copy it to the clipboard for use later, or you can Paste text already in the clipboard and it will be sent out through the internal modem port. The Select All menu item selects all the text within the Transfusion Demo window. This feature is very handy for changing the font to something more readable or copying everything to the clipboard. If the text you are about to copy to the clipboard is large, it is better to save the text and then load it from another application than to use the clipboard, as the clipboard wasn't meant to hold very large amounts of information. The Choose Font menu item lets you select the font for a particular selection of text or the entire TextEdit control. The default font is plain Courier 10 point. I highly recommend that you use either this font or Monaco 9 since they are of a reasonable size and they are mono spaced. If you want to go for speed, select Shaston 8 since it is optimized for speed with System Software v5.0.2, however, you will give up the consistency of a mono spaced font. I Thought You Said This Thing Could Send And Receive! ----------------------------------------------------- So far I've just dwelled on the terminal part of Transfusion. But yes, Transfusion can transfer files in the background! You can be in the Finder doing general file maintenance, or you can be editing icons with your favorite desktop icon editor, and at the same time be downloading the newest game off of a local BBS. This was the main reason Transfusion was written. However, since this is just a demonstration version, the send and receive options have been disabled. Not to worry though, we'll tell you what they can do in the real version of Transfusion. [Editors Note - The following options do NOT work in this demonstration version of Transfusion. However, we have included descriptions of them so that you can see just how powerful Transfusion really is.] The send menu allows you to send either straight text files with no error checking, or any type of file with the ever-popular XModem protocol. A text transfer is rather straightforward - Transfusion just reads the file and send it across to your internal modem port. An XModem transfer is a bit more involved - Transfusion reads the file and sends it across to your internal modem port with some additional information so errors in transmission (due to line noise or whatever) can be detected and corrected. When you select a send option, a standard file dialog appears and you can select the file you wish to send. A send window then pops up and the transfer continues until the entire file has been sent, the transfer is cancelled, or the transfer is suspended. The receive menu allows you to receive files with XModem-checksum or XModem-CRC. The checksum and CRC are different ways of detecting errors. Why can't you select whether to send in checksum or CRC mode? Well, in a few words, the receiver tells the sender what kind of error checking to use. The sender only follows what the receiver tells it. For most transfers, XModem-CRC should be selected because it is the most reliable protocol. Also, if the sending program does not support the CRC option, Transfusion will automatically sense this and step down to a checksum receive. When a receive option is picked, a standard file dialog box appears and you must type in the name of the file to receive. Unfortunately, the XModem protocol does not support sending file names with the data. Once you give the file a name, a receive window pops up and the transfer continues until the entire file has been received, the transfer is cancelled, or the transfer is suspended. A transfer is cancelled by one of three methods. The first is when the sender decides that the transfer should abort for some reason (like the operator at that end doesn't want the rest of the file to be sent, so he manually cancels it). The second is when the receiver decides that the transfer should abort for some reason. The third, and most nasty reason, is when ten consecutive errors occur during transmission. The transfer window displays the error count in two ways. The first is the total number of errors that have occurred, and the second, displayed in parenthesis, is the number of consecutive numbers that have occurred. What's All This Suspended Garbage, Eh? -------------------------------------- A great feature of Transfusion is its ability to "suspend" a file transfer. When you are transferring a file, you can click on the close box of the transfer window and the file transfer will enter a suspended state. Take note that the other computer you are connected to will not know about this and will eventually abort its transfer if enough time elapses without Transfusion restarting the transfer (this will not happen with text sends, however). To restart a transfer, just open Transfusion again by selecting its menu item from under the Apple menu. A dialog box will appear asking you if you want to attempt to resume the transfer. You now have the option of resuming it, or cancelling it. If you select resume, Transfusion will attempt to pick up where it left off. If you select cancel, Transfusion will enter terminal mode. If the remote computer is still trying to transfer a file when you select cancel, it will not know that Transfusion does not want to continue. The remote computer will continue to try transferring the file until it finally aborts due to timeout errors (the remoter computer waits a specified amount of time for you to send something across and if it doesn't get what it wants, it increments its error count). This can take a fairly long time. A nice trick to try is to type a few times, as this is the transfer cancel character. It takes two consecutive cancel characters, within one second, to abort the transfer. Sometimes a remote computer does not recognize the sequence (the cancel sequence is not really built into the XModem protocol, it's just a standard enhancement that Transfusion supports). A quick way out of this, if you are receiving, is to type , as this is the command that tells the sender that the packet it sent somehow got an error. The sender will then resend the packet, where you can then type again until the sender gets fed up with the number of errors and aborts. A quick way out of a situation where the remote computer doesn't recognize the sequence and you are sending is to type a few times. This is the command that tells the remote computer that you have finished sending the file. Not only can you suspend transfers within a single application, but if you quit the current application while Transfusion is transferring a file, launch another application that supports New Desk Accessories, and then open Transfusion again, Transfusion will know that it was previously transferring a file and present you with the restart dialog box. This also means that you can switch between two applications and remain on-line whether you are transferring a file, or just in plain terminal mode. IS THAT ALL? ------------ Basically, that's all there is to the Transfusion Demo. To learn more about how to use your modem and the internal modem port, you should check out the following articles in the July/August 1990, issue of GS+ Magazine: "Serial Port and Modem Commands", "XModem Briefly" and the "Transfusion Programmer's Guide". For More Information... ----------------------- I really hope that you enjoy this demonstration version of Transfusion. In the few months it has been available, Transfusion has become a favorite with our GS+ Magazine subscribers. What is GS+ Magazine? For the answer to that question, take a look at the file About.GSPlus, which should also be in the archive that this Transfusion Demo came in. Just in case it isn't, drop us a line at the address below, or give us a call at: Voice phone: (615) 870-4960 pro-gsplus BBS: (615) 875-4607 The Offer You Can't Refuse! --------------------------- Now that you've seen what the Transfusion Demo can do, how would you like to see the real thing? You would? Great! All you have to do is send a check or money order for $9 ($8 + $1 postage) in U.S. funds and payable to EGO Systems to the following address: GS+ Magazine - Transfusion Demo Offer P. O. Box 15366 Chattanooga, TN 37415-0366 Not only will you get the latest version of Transfusion, you'll get the latest issue of GS+ Magazine. The first IIGS _SPECIFIC_ Magazine + Disk publication. In the magazine, you will find great articles, vicious rumors, programming insights, and the best dang product reviews in ANY magazine for ANY computer! On the companion disk, you'll find not only Transfusion but the complete SOURCE CODE to Transfusion ! You'll also get the latest versions of our other programs, like EGOed. EGOed is a complete NDA text editor that allows you to read, edit and print, plain text files, AppleWorks Classic Word Processor files and Teach Text files from inside any other program that supports NDAs! It even allows you to... Hey, I'm giving all the surprises away! Thanks for taking the time to look at this demonstration version of Transfusion! Steven W. Disbrow Publisher of GS+ Magazine