Re: Re: RS485 - XPL on the wire

["Frank Mc Alinden" <fmcalind@xxxxxxxxxxxxxx>]

Hi Mal

> Why two PICs?  This guy has built a 64 channel DMX interface with a
> single 16F84 hanging off the parallel port.
> http://users.skynet.be/kristofnys/

Yes it does, and that would be perfect for the second pic 
;-)).....Remember
he doesnt have to parse any xPL messages...!!!..........

> I would have thought a more powerful PIC could deal with both the
> small amount of serial port traffic from the PC and sending the DMX
> data.

You could do that ,but my thoughts are based on which would be quicker if 
I
were developing.....

Two smal pics (16f84) are around $8 each which is the same  price as a
16f876.....only extra component would be a crystal and a couple of
caps.........
Just my thoughts on it
Frank

----- Original Message -----
From: "Mal Lansell" <mlansell@xxxxxxx>
To: <ukha_xpl@xxxxxxx>
Sent: Sunday, October 24, 2004 2:59 AM
Subject: [ukha_xpl] Re: RS485 - XPL on the wire


>
>
> --- In ukha_xpl@xxxxxxx, "Frank Mc Alinden"
<fmcalind@b...>
> wrote:
>
> >
> > So each node must have its light level refreshed every so
> often...Sounds
> > like the dmx stuff would require its own  rs485 network ..????
> >
> > Just had a browse and read some dmx512 stuff.......My thoughts on
> an xPL
> > Hardware interface would be as follows...
> >
> > Have a device which has two pics , One to listen to the xPL
Network
> > connected via rs232.. and the other to Transmit the dmx data and
> keep track
> > of the dimmer channel levels......Connect an 8 bit port between
> each device
> > and have a couple of control lines ie a data / node line to tell
> the dmx pic
> > that the info on the 8 bit port is either data (light level) or
> channel
> > number ...So two bytes would be transferred  between the pics
with
> every
> > xPL-DMX command received ...........
> >
> > Frank
> >
>
> Why two PICs?  This guy has built a 64 channel DMX interface with a
> single 16F84 hanging off the parallel port.
> http://users.skynet.be/kristofnys/
>
> I would have thought a more powerful PIC could deal with both the
> small amount of serial port traffic from the PC and sending the DMX
> data.
>
> Mal
>
>
>
>
>
>
>
>
> xPL Links: http://www.xplproject.org.uk http://www.xplhal.com
http://www.xpl.myby.co.uk
> To Post a Message: ukha_xpl@xxxxxxx
> To Subscribe:  ukha_xpl-subscribe@xxxxxxx
> To Unsubscribe:  ukha_xpl-unsubscribe@xxxxxxx
> Yahoo! Groups Links
>
>
>
>
>
>
>