Sending ps/2 signal to computer??

wilshire

Hi,

In my project, I am trying to read the speed and direction of two quadrature encoders. Based on the speed of the encoders, I want to move the mouse up/down or left/right on the screen. The mouse drivers I've seen in OBEX seem to only read from a mouse rather than send a mouse signal to the computer. Does anyone know how I can do this?

ElectricAye

Maybe I don't really understand what you are trying to do but it seems to me that you do not need any mouse drivers at all. Instead, take whatever readings your encoders are giving you and convert those readings into some kind of graphic display on your VGA or TV using one of those VGA or TV objects from the OBEX. You can create whatever kind of cursor character you want from the available ROM font that the Propeller provides, and based on whatever ranges of encoder values you might select, you can can have the "cursor" on your screen change colors or shapes or whatever makes you feel good.

Maybe you could elaborate a little on what you are trying to do.

James Newman

He wants to generate a ps/2 mouse signal, not receive one.

Shouldn't be too hard at all, heres a random link:

http://www.computer-engineering.org/ps2protocol/

wilshire

James Newman said...
He wants to generate a ps/2 mouse signal, not receive one.

Shouldn't be too hard at all, heres a random link:

http://www.computer-engineering.org/ps2protocol/

Exactly... thanks for the link. So just to be clear, I can send an out signal to the computer using the ps/2 port of the propeller demo board?

What we are tying to do is build a motorized wheelchair simulator for disabled/mentally challenged people. The wheelchair is placed on a set of rollers (to constrain physical movement) and two encoders track the motion of the wheels. The signal from the encoders should be converted to a ps/2 signal so that a computer can read it like a mouse. The movement of the 'mouse' is then used to navigate through a virtual world, written in VRML.

Being the complete noob that I am, I feel like I'm in way over my head and don't even know where to start. Any advice is greatly appreciated!

TonyWaite

Hi,

One approach would be to use a Basic Stamp (also from Parallax), because the hardware is so
easy; and a number of people have published PS2 mouse emulators for it!

For example

(http://www.colinfahey.com/ps2_mouse_and_basic_stamp_computer/ps2_mouse_and_basic_stamp_computer_en.html)

I always try and go the easiest way first ...

Regards,

T o n y

ElectricAye

wilshire said...
....

Being the complete noob that I am, I feel like I'm in way over my head and don't even know where to start. Any advice is greatly appreciated!

Much depends on whether or not you've had any experience working with micro controllers. If you are starting out from the very beginning, then you might want to look at the Basic Stamp and the unit "What's a Microcontroller?" Parallax is world famous for their educational units involving the Stamps and these forums are extremely helpful.

www.parallax.com/StoreSearchResults/tabid/768/List/0/SortField/4/ProductID/327/Default.aspx?txtSearch=what's+a+microcontroller

The Propeller is a much more powerful chip and more and more people here on this forum have suggested that it, too, is good for newbies. For the Propeller, there are kits like the Propeller Education Kit, which has a number of labs that will walk you through all the concepts concerning cogs, etc.

www.parallax.com/StoreSearchResults/tabid/768/List/0/SortField/4/ProductID/415/Default.aspx?txtSearch=propeller+Education+Kit
www.parallax.com/StoreSearchResults/tabid/768/List/0/SortField/4/ProductID/506/Default.aspx?txtSearch=propeller+Education+Kit

http://forums.parallax.com/showthread.php?p=617192

So don't feel overwhelmed. If I can learn this stuff and get useful devices as a result, believe me anyone can!

Let the forum know what is your background and I'm sure people here can lead you to where you need to go.

cheers,
Mark

Kye

Making a PS2 mouse emulator is hard. Read the information at http://www.computer-engineering.org/ps2protocol/.

It will explain everything to you. However, I reconmend studying some of the PS2 mouse drivers published also in the obex for how to communicate.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Nyamekye,

wilshire

Thanks for the help. It's good to know now that what I am trying to do is actually possible... and that I've found the right tool to do it. I actually ordered the Basic Stamp Homework board only to find out that it's processing speed was not high enough for this application. Both encoders are expected to output about 160 counts/sec.

I've gone through the 'What's a Microcontroller Book' and now I am going through the Spin tutorial in the propeller tool... I may return later with some more specific questions.

Cluso99

Don't forget that you cannot just connect a normal PS2 cable. You will need to cross the data/clock pins (or reverse in software), connect the ground pin, but DO NOT connect the 5V pin as both ends will be supplying power (it is used to power the mouse).

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Links to other interesting threads:

· Home of the MultiBladeProps: TriBlade,·RamBlade,·SixBlade, website
· Single Board Computer:·3 Propeller ICs·and a·TriBladeProp board (ZiCog Z80 Emulator)
· Prop Tools under Development or Completed (Index)
· Emulators: CPUs Z80 etc; Micros Altair etc;· Terminals·VT100 etc; (Index) ZiCog (Z80) , MoCog (6809)·
· Prop OS: SphinxOS·, PropDos , PropCmd··· Search the Propeller forums·(uses advanced Google search)
My cruising website is: ·www.bluemagic.biz·· MultiBlade Props: www.cluso.bluemagic.biz