Hello,
--- On Mon, 6/8/09, Clark Martin <[email protected]> wrote: > The Mac Plus and earlier mice use discrete signals (wires) > carrying the mouse click and encoding phases (two each) of the mouse X > & Y directions (as well as power and ground). ADB (Apple Desktop > Bus) transmits data bi-directionally on it's bus. It can do this for a > number of devices connected to the same bus. It is much like USB > although slower and limited in available devices. Let me see if I understand this correctly: The primary difference between a Mac Plus mouse and an ADB mouse is that, in the former, there is very little circuit decoding done inside of the mouse: the decoding is done by the Mac itself. But the ADB mouse is able to perform most of the decoding work inside itself and send data signals direct to the CPU indicating what is happening to the mouse at any given time. Does that sound right? > There were devices sold way back when that let you use one > with the other but I can't recall off hand if two devices were made, > one for each direction (Mac+ Mouse / Keyboard used with an ADB Mac and > one to connect ADB mice and keyboards to Mac Pluses and earlier) or if it > was just one of those functions. Any any event they didn't last > long and are going to be VERY hard to find now. > > Such a device would have included a small microprocessor in > it to convert one to another. So in the case of using an ADB mouse with a Plus's DE-9 port, such a microprocessor would be necessary in order to decode the ADB mouse's signals into a form that the Plus's CPU could understand, yes? > You cannot simply wire one to another, as above a CPU would > be needed to translate between them. Drat. Well, between your explanation and Mac128DOTcom's earlier post, I think I (might) now finally understand the need for a microprocessor in order for such a hack to work. Best, James Fraser --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Vintage Macs group. The list FAQ is at http://lowendmac.com/lists/vintagemacs.shtml and our netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/vintage-macs?hl=en Low End Mac RSS feed at feed://lowendmac.com/feed.xml -~----------~----~----~----~------~----~------~--~---
