MULTITASKING AND TELECOMMUNICATIONS On-Line Version Last Revised: March 25, 1993 Supra Corporation - World Headquarters 7101 Supra Drive SW, Albany, OR 97321 General: (503) 967-2400 Fax: (503) 967-2401 Sales: 7:00am - 5:00pm PST, M-F (503) 967-2410 (800) 727-8772 Supra Tech Support: 8:00am - 4:30pm PST, M-F (503) 967-2440 GENERAL (503) 967-2490 IBM DOS & Other Products (503) 967-2491 IBM WINDOWs (503) 967-2492 MAC (503) 967-2493 AMIGA Supra BBS........(503) 967-2444 8 lines 24 Hours v.32bis v.42bis LAPM 2-5 CompuServe.......76004,565 BIX..............SupraCorp America Online...SupraCorp2 GEnie............SupraTech AppleLink........D2456 UseNet EMail.....supratech@supra.com ------------------------- (Article Begins Here) ------------------------- Multitasking computers allow you to do many different things while other operations take place in the background. Although you don't see them in progress, background operations can be complex and can sometimes demand too much of your computer's attention to allow high-speed communications. High- speed transmissions are more reliable in a single-user situation with as few applications as possible in use. This section lists some specifics which can interfere with high-speed communications, depending on your platform. Amiga Workbench 2.x allows transmission rates about 100% faster than Workbench 1.3, which limits you to 9600 bps reliably. Background tasks, graphics modes, SCSI interfaces and hard drives all can have an impact on the actual transmission rate. With WB 2.x, you should be able to achieve reliable serial port speeds between 9600 and 19,200 bps, depending on CPU model and speed. The SupraTurbo 28 accelelerator also helps alleviate this problem. Macintosh AppleTalk/AppleShare activity (including printing) can lower the transmission rate because this activity has a higher priority than other serial communications. Some INITs and CDEVs may also cause problems. PCs & Compatibles Please also see the "Faster UART Chip" section in the SupraFAXModem V.32bis Important Information manual. TSR (terminate and stay-resident) programs can also slow the transmission rate. For throughput over 19,200 bps, your computer should have a 386 or faster processor. Multitasking performance varies between operating systems: Windows 3.0 will often have problems at serial port speeds (computer rates) higher than 9600 bps. Windows 3.1 correctly supports up to 38,400 bps with a 16550 UART. Windows NT and OS/2 have no problems with multitasking. All Platforms - Displays If you are downloading text that is displayed on your screen as it is received, you may have problems with your computer's display keeping up with the speed of the incoming data. One way to get better performance is to change your display to a lower number of colors, or monochrome, so it is more efficient. All Platforms - Processor Speed Another general rule is the faster processor that your machine has, the better it will be for high-speed transfers. A 68030 or 386/486 machine will probably do better than a 68000 or 80286. -------------------------- (Article Ends Here) -------------------------- Copyright 1993 Supra Corporation Supra Corporation, and SupraModem are registered trademarks of Supra Corporation. SupraFAXModem, SupraSmartUART, SupraTurbo, and Silent Answer are trade- marks of Supra Corporation.