CompuServe Thread

#Serial Port speed

6 messages in this thread
#2359From: Eric KadisonOct 10, 1991 1:34 AM
Hi Sysop: Can you give me an idea of the capabilities of a Visual Basic serial port under Win 3.0 Enhanced? Does VB and Win 3 Enh provide serial data buffering at the interrupt level for received data? If so, how many characters of buffering are provided? This turnkey application will run on a 486/33 with several tasks running concurrently — including an imaging task. So it would not be suprising if the reception of high speed data over a serial port required a more sophisticated serial data support library. Any ideas? Thanks, Eric There are 2 Replies.
#2393From: Mark Novisoff/MicroHelpOct 10, 1991 8:16 AM
Eric, There are three ways to do communications in Visual Basic: 1. The least practical is to use OPEN with "COMn", because it depends on the default settings the user has set, i.e., you cannot specify the baud, parity, data and stop bits. 2. The hard way is to use the Windows API calls directly. There are two or three examples of doing this in DL1 and/or DL6. (They may still be in the MSLANG forum.) 3. The easy way is to use an add-on library, such as my company's communications library. In addition to making it very easy to send and receive data, we provide many file transfer protocols including XMODEM, YMODEM, YMODEM-G, ZMODEM and CompuServe B+. As a bonus, the two versions of our product (one for QB/PDS and the other for VB) are about 95% code-compatible. That means you can move code between the two platforms with only minor changes (if any). With methods 2 and 3, you can specify the buffer size that Windows should use for capturing data. Mark There is 1 Reply.
#2571From: Eric KadisonOct 11, 1991 1:38 AM
Mark, Good to find someone with a comm library that runs under Win 3 Enh. Does your library include a driver that handles interrupts before Win gets control of them? (i.e. Is it Win API compatible?) Can you keep up with some reasonable thruput by taking control of the UART? (9600 Baud with other tasks running) Is that software compatible with Dynacomm Async from FutureSoft? If so, how? We will likely prototype our app with this software. What is the name and price of this library? Information?? Where is it available? Thanks, Eric There is 1 Reply.
#2589From: Mark Novisoff/MicroHelpOct 11, 1991 6:53 AM
Eric, We do not include a driver. Our library provides an easy-to-use wrapper around the Windows API services. Because we use only standard Win API calls, our library will work with any comm driver that is compatible with the Windows COMM.DRV. I run it at 9600 on my system regularly and don't have any problems. We do *not* take control of the UART. Is it compatible with Dynacomm Asynch? I have no idea. If it is not, then I would suspect the other software because we aren't doing anything that is undocumented. The name is "MicroHelp Communications Library" and it's priced at $149. I'll be happy to send you a brochure and demo if you'll leave me your address in a MAIL message. Mark
#2442From: Don FunkOct 10, 1991 12:16 PM
Hi Eric, I would address this to both Ethan Winer and Mark Novisoft to see if there product would address what you are trying to accomplish. Don Funk There is 1 Reply.
#2492From: Mark Novisoff/MicroHelpOct 10, 1991 4:10 PM
Don, As much as I wish my name were spelled "Novisoft", it's not! <smile> Mark