Lightning Systems Product Information Sheet
Lightning Systems
Copyright (c) 1995 Apple Users' Group, Sydney
Republished from Applecations, a publication of the Apple Users' Group, Sydney, Australia.
Lightning Systems offers two (2) products for the Apple II line of computers.
6551-ACIA
---------
This is a replacement chip for the 6551 ACIA (Asynchronous Communications Interface Adapter) that is standard on most Serial Interface cards for the Apple II.
Why do you need a replacement chip? Simple, the 6551 chip that is on most Serial Interface cards has a design flaw in it that causes it to lose a character every time the CTS line is switched.
In most cases, this is not a problem. However, with modem speeds continuing to rise, people have started using Hardware Handshaking cables to connect their computers to their modems to achieve even higher speeds. This is where the problem lies.
In typical Hardware Handshaking installations, the computer is sending and receiving faster than the modem can receive and transmit data. This means that the computer and the modem need to communicate between themselves to tell each other when it's ok to send or receive data. When the buffer fills up, the modem switches the CTS (Clear To Send) line to notify the computer that it is no longer ok to send data. At this point the 6551 chip stops sending data immediately! This is bad. The 6551 may have been right in the middle of sending a character (normally 10 bits). That character is now lost causing an error in the transmission.
This is where the 6551-ACIA comes in. This new 6551 chip fixes the problem.
This is a direct replacement for the 6551 chip you now have.
Turbo ASB
---------
Do you have a high-speed modem, or other high-speed serial communications device?
Did you know that most Serial Cards for the Apple II are limited to only 19.2k bps?
Well, they don't have to be anymore. The Turbo ASB can blow away that nasty 19.2k bps barrier. With the Turbo ASB, your serial communications can run as fast as 230,400 bps!!!
The Turbo ASB is an add-on card replaces that pokey old 6551 chip on your Serial Interface Card and transforms it into a speed demon.
The Turbo ASB supports all the standard bps rates you are used to, (slow.) and adds 38.4k, 57.6k, 115.2k and 230.4k!
At this time the Turbo ASB is supported by ProTERM, Spectrum and ANSITerm. The Turbo ASB includes a 6551-ACIA chip.
Pricing
-------
The 6551-ACIA is US$4.00 each. The Turbo ASB is US$27.00 each.
Overseas shipping and handling is US$10.00 per order.
Include an E-Mail address if you have one.
Lightning Systems
P.O. Box 4
Mukwonago, WI 53149-0004
(414) 363-4282 BBS
sjensen@cello.gina.calstate.edu

THIS CONTENT COPYRIGHT © 2007, APPLE MACINTOSH USERS' GROUP, SYDNEY
Permission has been obtained to make this material available on the Internet.

Permission is hereby granted for non-profit user groups to republish this content.
PLEASE CREDIT THE AUTHOR AND THE SOURCE: Applecations, publication of the Apple Users' Group, Sydney, Australia

THIS PAGE COPYRIGHT © 2007, ANDREW ROUGHAN