Gallery, Projects and General > The Design Shop

Concept for anemometer......

<< < (5/5)

andyf:
This is off John Hill's topic. because he is more concerned with interfacing a pukaru keyboard ( :scratch: never heard of one before) to a PC, but a simple anenometer could made with the pitch circle of its vanes the same diameter as a small cycle wheel. Then, with the actuating magnet mounted on one of the spokes of the anenometer, a cycle speedo could be used to display the speed either in mph or kph.

Andy

John Hill:

--- Quote from: BillTodd on December 23, 2010, 10:05:32 AM ---The principle problem with using a keyboard is the way its input is handled by the operating system. In a multi-tasking system like windows or linux the key inputs will be passed to whatever application has the current focus, so unless you are prepared to dedicate a pc to the task of wind speed monitoring, it's not an idea solution.
--- End quote ---

Thats true Bill but what you can do is write a keyboard 'hook'  which will see every message between the hardware drivers and winderz proper.  You can also at that point (in current versions of winderz) identify which keyboard the message came from.



--- Quote ---Serial inputs (com ports) are useful because the driver usually takes care of unused data without causing too many problems. Parallel ports (printer ports) can also be used but usually require some extra hardware knowledge. Sadly both ports are disappearing from new machines, as they are replaced by USBs.  USBs requires a ridiculous amount of software at both ends to use natively (i.e. as a Human Interface Device), but at least there are cheap USB-serial adapters that turn them into comports.

Bill

--- End quote ---

Serial ports are quite useful for the pc modder (but not as much as they used to be for W95 and before). They are particulary useful having bi-polar output and I suppose they could easily be used to drive an H bridge but there are not many lines available for output,  Txd, Rts, Dtr and I think thats about it, inputs are Rxd, Cts, Dsr, Dcd, Ri.  Of course if you go further and use a UART in your project you can get 8 bits in and out plus  some of the control lines.  Serial ports used to be very useful when it was still easy to write interrupt service routines that would be handled immediately not when the operation system go around to it, it is much harder nowadays.

But serial ports are not what I was trying to invoke madmodder interest in.

I would not recommend parallel (printer) ports for madmodder hacks as it seems to be very easy to kill the PC port circuitry.

The point I was trying to demonstrate is that using a keyboard pcb ('pukaru' means broken in this country) gives an easy method of sending several different messages to the program, the demonstration example I gave used a multi postion switch to indicate wind direction (a cheap and readily available 12 position switch would give 30 degree visions of the compas).  I choose an anemometer as an example as I thought people would easily understand what is required and if you were prepared to dedicate a PC to the task the software could be written in the most simple of languages by an absolute beginner,  the anemometer would be the exercise to take right after writing one's first 'Hello World' program.

I agree that the USB protocols are not for the beginner computer modder but USB has its place, for example in my anemometer example I would look for a USB keyboard to hack.

John

Navigation

[0] Message Index

[*] Previous page