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Off the shelf controller chipset or PCB?

Started by R.G. May 23, 2005
Hi,

I'm working on a control panel-like device that has a bunch of on/off
buttons (100-200), a control knob (that drives an optical encoder) and
an LCD display.  The controller will interface with and control some
software running on a PC via USB or CAT-5 or something similar.

Does anyone know of some standard or off the shelf PCB/chipset solution
for such a controller? It seems like a relatively simple design in
terms of signal complexity and routing; just a bunch of digital IO's
plus a counter or two, in addition to a chip to drive the LCD, all
interfacing with a programmable CPU.

What kind of processor will I need? Memory? The LCD chips? I've never
done this sort of design before, and perhaps have a superficial
understanding of what's involved. Once I have the PCB built, I feel
this will be mainly a programming project.

Is there a firm that specializes in this kind of glorified 'remote
control' PCB/chipset design? Do turnkey solution exist for this
application?

Thank you for any advice you can provide. It is much appreciated.

R.G.

R.G. wrote:
> Hi, > > I'm working on a control panel-like device that has a bunch of on/off > buttons (100-200), a control knob (that drives an optical encoder)
and
> an LCD display. The controller will interface with and control some > software running on a PC via USB or CAT-5 or something similar. >
It would be difficult to find a controller chip with 100s of I/O.
> Does anyone know of some standard or off the shelf PCB/chipset
solution
> for such a controller? It seems like a relatively simple design in > terms of signal complexity and routing; just a bunch of digital IO's > plus a counter or two, in addition to a chip to drive the LCD, all > interfacing with a programmable CPU.
The easiest way to do it is to use several CPLD programmed as parallel loaded shift registers. The controller chip enables loading 100s of inputs and shift in the data. A simple microcontroller can easily do the job, as well as driving an LCD.
> > What kind of processor will I need? Memory? The LCD chips? I've never > done this sort of design before, and perhaps have a superficial > understanding of what's involved. Once I have the PCB built, I feel > this will be mainly a programming project.
How big and what types of LCD? Dumb or smart LCD?
> > Is there a firm that specializes in this kind of glorified 'remote > control' PCB/chipset design? Do turnkey solution exist for this > application? > > Thank you for any advice you can provide. It is much appreciated. > > R.G.
linnix wrote:

> The easiest way to do it is to use several CPLD programmed as
parallel
> loaded shift registers. The controller chip enables loading 100s of > inputs and > shift in the data.
OK. I apologize, but I'm not too familiar with this stuff, so I'm a bit unclear. How would the controller and my many IO's be connected to the shift registers? When a button is pressed, what exactly will happen in the shift register, and what will my controller read (and where)?
> How big and what types of LCD? Dumb or smart LCD?
My LCD would be at most 320x240 pixels and be programmable, so hopefully I can use graphics libraries to display data sent back from the PC. I hope this helps. Thanks again.
are your switches toggle action or simply push button type actuation?

Is more than a couple of buttons going to be operated at any one time?

If they are simply pushbuttons and don't have many simultaneous operations
it is possible to connect them in a matrix and scan them, maybe 15 x 15.

Phil



"R.G." <rkg22@hotmail.com> wrote in message
news:1116899909.727033.259300@f14g2000cwb.googlegroups.com...
> linnix wrote: > > > The easiest way to do it is to use several CPLD programmed as > parallel > > loaded shift registers. The controller chip enables loading 100s of > > inputs and > > shift in the data. > > OK. I apologize, but I'm not too familiar with this stuff, so I'm a bit > unclear. How would the controller and my many IO's be connected to the > shift registers? When a button is pressed, what exactly will happen in > the shift register, and what will my controller read (and where)? > > > How big and what types of LCD? Dumb or smart LCD? > > My LCD would be at most 320x240 pixels and be programmable, so > hopefully I can use graphics libraries to display data sent back from > the PC. > > I hope this helps. Thanks again. >
Many are toggle, but there are also many that are pushbutton action
(i.e. something happens after a quick press and release).  Some of the
pushbutton action switches will be used together to invoke special
functions, like a Shift or Alt key.

R.G. wrote:
> Many are toggle, but there are also many that are pushbutton action > (i.e. something happens after a quick press and release). Some of
the
> pushbutton action switches will be used together to invoke special > functions, like a Shift or Alt key.
Perhaps you can use a combination of scanned matrix and true registered input. Shift and Alt types needed to be registered, but action keys does not. Another question is whether the state of your switch board need to be preserved during power cycles. If so, scanned matrix won't work.

"R.G." wrote:

> Hi, > > I'm working on a control panel-like device that has a bunch of on/off > buttons (100-200), a control knob (that drives an optical encoder) and > an LCD display. The controller will interface with and control some > software running on a PC via USB or CAT-5 or something similar. > > Does anyone know of some standard or off the shelf PCB/chipset solution > for such a controller? It seems like a relatively simple design in > terms of signal complexity and routing; just a bunch of digital IO's > plus a counter or two, in addition to a chip to drive the LCD, all > interfacing with a programmable CPU. > > What kind of processor will I need? Memory? The LCD chips? I've never > done this sort of design before, and perhaps have a superficial > understanding of what's involved. Once I have the PCB built, I feel > this will be mainly a programming project. > > Is there a firm that specializes in this kind of glorified 'remote > control' PCB/chipset design? Do turnkey solution exist for this > application? > > Thank you for any advice you can provide. It is much appreciated. > > R.G.
Almost Anything 8 to 32 bits. If you are only building 1 and do not want to make boards go big with a PC104 set up or an industrial PLC. If you want to build a PCB smaller CPUs are OK. You can Poll Shift Registers or latches. If you want to use a matrix you will need diodes so you can read all possibilities. TCP/IP or USB find something that inclues it, or it is a lot of work. You can use a n RS232 to USB chip (FDTI or SiLabs) to avoid and work on it. Good Luck
linnix wrote:
> R.G. wrote: > >>Hi, >> >>I'm working on a control panel-like device that has a bunch of on/off >>buttons (100-200), a control knob (that drives an optical encoder) > > and > >>an LCD display. The controller will interface with and control some >>software running on a PC via USB or CAT-5 or something similar. >> > > > It would be difficult to find a controller chip with 100s of I/O. > > >>Does anyone know of some standard or off the shelf PCB/chipset > > solution
Yea, a $10 keyboard for a PC plugged into a micro controller which drives a standard LCD module. 2 lines needed for keyboard, 6 lines for LCD. Quadrature encoder uses 2 more lines. 1 line to transmit serial data. PIC16F628 should do the trick. If you need a few more lines for other stuff, use the PIC16F870. Both have hardware UART function. -- Luhan Monat: luhanis(at)yahoo(dot)com http://members.cox.net/berniekm "Any sufficiently advanced magick is indistinguishable from technology."

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