DOWTDD.THD --- Copyright 1987 by Phil Wheeler An original compilation of Compuserve Model 100 Forum messages for use by Forum members only. Downloading to disk is a major improvement over having to rely on RAM storage for downloads -- paricularly if a 1200 baud modem is in use. The Chipmunk (and DVI) disk drives are able to provide this capability. Unfortunately, the Tandy Portable Disk Drives (TDD & TDD2) suffer in this regard, due to their use of the RS-232 for interfacing with the computer. This file captures typical messages on this subject. Message range: 143330 to 144482 Dates: 3/18/87 to 4/3/87 Fm: kent hughes 76576,3060 To: all hello all, need some quick help it at all possible I'm kind of a rookie (and noticeably new) but have just picked up an(old I think) tandy portable drive. THE QUESTION IS: Can I download dl files and, while on line, dump to disk an entire file that may be larger than available ram??? Also, is there a place where I can get some assistance in downloading protocol? Like, what is Compuserve 'A' and 'B' versus XMODEM ... I'm also looking for text editing assistance programs,spreadsheet and dbase type programs to help with organizing on this great little m100 - any help?? Fm: Tony Anderson 76703,4062 To: kent hughes 76576,3060 In general, no you cannot download directly to the disk. Has nothing to do with the drive, but with the fact that the computer has only one communication chip, and when it is being used for the modem operation, it cannot also communicate with the RS-232 port, where the disk drive is plugged in. Now the whereases and wherefores.... There are a number of ways to "simulate" the download to disk function, depending on how far you want to go technically, and how much you're willing to spend making it happen with a cheap disk drive. For the same amount of money invested, you could have bought a disk drive (the Chipmunk) which would download to disk with no problems. Of course other limitations also involve which computer you are using; they all have different ways of working... Anyway, for starters, you can read the three files in DL3, DSKTRM.100, DSKTRM.DOC, and DSKTRM.CMT. That's one approach. Then you can explore the idea of buying Disk-Power, an alternate DOS for the drive, and using it with acoustic cups. See DISKOS.INF in DL13; the DPTIP series in DL9 (four files), and the DPUSER series in DL9 (another four files). If you have a Tandy 200, then Disk-Power seems the way to go, and Mel Snyder 70136,1007 will definately contact you to extol the virtues of the 200/T I have personally recommended that folks get and use and external modem. In addition to greater speed, 1200 baud operation, with an external modem, you and put the modem on hold, while accessing the disk. So you can download to a buffer file, then save the buffer file to the disk, then go back to the modem for more. I do it all the time, with never any problems. Whatever you decide, and whatever your configuration, good luck... Fm: Tony Anderson 76703,4062 To: LARRY R. 72516,475 The TDD, and the TD2 plug into the RS-232 port of the computer. The computer has only one communication chip, and when it is being used to communicate with the modem, it cannot also communicate with the RS-232 port. Thus, it is physically impossible to upload from, or download to, the TDD disk, directly. Since it is impossible, there is no software which will do it for you. There have been reports that users with Disk-Power, one of the alternate DOS's for the TDD, have been able to download to disk, although the exact method is unclear to me. But it has to do with how Disk-Power connects into the operating system hooks, and the fact that it can communicate with the RS-232 port independently of the modem chip. How, I don't know. For some information on this, read the DPTIP and DPUSER series of files in DL9, a total of 8 files. You can also "simulate" the function by using an external modem to hold the connection, while you go offline to dump a RAM buffer to the disk; see DSKTRM in DL3, three files. However, if you buy an external modem, you can also disconnect from the modem, while it holds the line, and do whatever you want to with the disk. Download to a RAM file, disconnect, save the file to the disk, reconnect, and get more of the stuff you're downloading. None of these options are truly satisfactory. By the time you buy extra software, or extra hardware, or both, you will have as much invested in making your system "simulate" the function, as if you had bought a Chipmunk Disk Drive to begin with. The Chipmunk does all that without the problems. Fm: Martin Zimmerman 72757,3076 To: Tony Anderson 76703,4062 It is my understanding that the RS-232 port AND the modem chip are both connected to the same UART which then communicates with the Model 100. There is a 'bit' on one of the output ports that switches the inputs. Most of the DOS's I've seen for tle TDD-1 (and probably the TDD-2? I don't know I'm in CANADA, where they still have not introduced it...) seem to switch this, AND also send out the 'bit' that disconects the phone from the Model 100. It is the disconecting that "hangs you up" not the switching. I would have to believe that the modem chip can produce a carrier without having to 'talk' to the Model 100, after all that's what it does when I- no type, you- no type... If your software were to switch and NOT play with the phone relay, than all would be okay..... The procedure would be... Send ^S to host... Flip Dump data to TDD (at 19200 baud this would NOT take long...) Flip Send ^Q to host. Continue with whatever... Fm: Tony Anderson 76703,4062 To: Martin Zimmerman 72757,3076 The cause of the problem is known, and it's only partially the bit you indicate. The other part is the code that responds to that bit in the background task, and opens the "connect" relay. There have been a number of people, who have indicated, "Oh, it's a simple problem to get around, we can do it in software..." So far, NONE of them have ever been able to do it. Apparently the resident code is designed so that you cannot talk to the RS-232 port, and have the modem connected to the phone line at the same time. We generally don't go into great detail when folks ask about it, since most folks don't understand the workings of the code anyway. But, if you think you can see a way around the problem, then have at it! It would be of great benefit to the TDD users to be able to download directly to disk, in any manner possible. I would think, that if you avoided the TELCOM code entirely, and wrote a whole new terminal emulator in assembly langauge, that you could get around the problem since you could avoid the "automatic disconnect" portion of the code. But I'm not up to writing such a program yet, so it's up to someone else with more smarts than I. Fm: Martin Zimmerman 72757,3076 To: Tony Anderson 76703,4062 Well, I have to agree that in theory it seems simple, but to actually write the code is a completely different matter. I too am not up to that yet. But I would be if I ever found out the command protocol for the TDD, then I would try to write a new TERMINAL program. It would have to be in ML as nothing else on the 100 can 'talk' at a constant 19200 baud and not lose anything. If I ever do get around to it, then there would be no need for FLOPPY.CO to be resident for the terminal to work (with disk...) Fm: Mark Earle 73117,351 To: All Wonder if there is a program to allow direct downloading from the internal modem to the PDD-2; and also once the file would be on the PDD-2, a way to read it, and/or print it, if the file was larger than the available M100 memory.....?? Mark Earle 73117,351 Fm: Tony Anderson 76703,4062 To: Mark Earle 73117,351 You cannot download directly to the TD2 because it connects to the RS-232 port. The computer has only one communication chip, and when it is being used to "talk" to the modem, it cannot also be used to "talk" to the RS-232 port and the disk drive. No way has yet been found around this problem, except via "simulation, where you download to RAM, and via one scheme or another, disconnect from the modem line, and save the data to the disk, then go back for more. This requires, at the very least, a way to keep the communications line operational, meaning an external modem; and probably one of the alternate DOS's for the disk drive, which there are none of yet for the TD2. See the 3 files named DSKTRM in DL3 for starters, the DPUSER and DPTIP series of files in DL9, 8 files.