AVR-Chat

Hello,

I am doing a project where I need multiple mega8 avrs sending sensor
data to another controller.  The other controller is an OOPic-R.  The
OOPic has built in functions for SPI, i2c(twi), and serial
communications.  What is best for a multiple slave, single master
system?  I can make code for the OOPic, but need some slave code for
the avrs.  I am using Codevision and the help file doesn't have that
much information about how to use i2c or SPI in slave mode.

Thanks,
Kc

mega8 has serial port, why not use RS485 communication
bus. Single Master, multiple slaves (32 directly
supported, 128 possible with better driver ic's),
minimal IO requirements (TX,RX,direction pin). One
question however, are you doing onboard comm.?

Murat Karadeniz



--- ckbanner <kcbanner@inbox.lv> wrote:
> Hello,
> 
> I am doing a project where I need multiple mega8
> avrs sending sensor
> data to another controller.  The other controller is
> an OOPic-R.  The
> OOPic has built in functions for SPI, i2c(twi), and
> serial
> communications.  What is best for a multiple slave,
> single master
> system?  I can make code for the OOPic, but need
> some slave code for
> the avrs.  I am using Codevision and the help file
> doesn't have that
> much information about how to use i2c or SPI in
> slave mode.
> 
> Thanks,
> Kc
> 
> 


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HOw do I connect more than one mega8 slave to one master? I know rX
and TX, but what do you mean by direction pin?  I thought serial prot
was for connecting two micros together.  What do you mean by onboard
comm?  

Thanks for the fast reply!

-Kc



--- In AVR-Chat@yahoogroups.com, MuRaT KaRaDeNiZ <karademu@y...> wrote:

> mega8 has serial port, why not use RS485 communication
> bus. Single Master, multiple slaves (32 directly
> supported, 128 possible with better driver ic's),
> minimal IO requirements (TX,RX,direction pin). One
> question however, are you doing onboard comm.?
> 
> Murat Karadeniz
> 
> 
> 
> --- ckbanner <kcbanner@i...> wrote:
> > Hello,
> > 
> > I am doing a project where I need multiple mega8
> > avrs sending sensor
> > data to another controller.  The other controller is
> > an OOPic-R.  The
> > OOPic has built in functions for SPI, i2c(twi), and
> > serial
> > communications.  What is best for a multiple slave,
> > single master
> > system?  I can make code for the OOPic, but need
> > some slave code for
> > the avrs.  I am using Codevision and the help file
> > doesn't have that
> > much information about how to use i2c or SPI in
> > slave mode.
> > 
> > Thanks,
> > Kc
> > 
> > 
> 
> 
> __________________________________
> Do you Yahoo!?
> Free Pop-Up Blocker - Get it now
> http://companion.yahoo.com/

Seems Micro$oft is on the money grab again

http://www.microsoft.com/mscorp/ip/tech/fat.asp

It seems they want to now start charging for use of their FAT file system.

Not good news...

Matthew

On Sat, Dec 06, 2003 at 09:49:37AM +1030, Matthew Cook wrote:
> Seems Micro$oft is on the money grab again
> 
> http://www.microsoft.com/mscorp/ip/tech/fat.asp
> 
> It seems they want to now start charging for use of their FAT file system.
> 
> Not good news...

Microsoft try to make out that that they date back to 1976.
 "The first FAT file system was developed by Microsoft in 1976"

These are the Patents which Microsoft cite further down the page.
I've take the liberty of providing the dates and the titles of the
Patents, as per www.uspto.gov

5,579,517 November 26, 1996
	Common name space for long and short filenames

5,745,902 April 28, 1998 
	Method and system for accessing a file using file names
	having different file name formats

5,758,352 May 26, 1998 
	Common name space for long and short filenames

6,286,013 September 4, 2001 
	Method and system for providing a common name space for long
	and short file names in an operating system

Make up your own mind if that indicates that Microsoft is run by a
bunch of desperate, money-grabbing sleaze-bags.

-- 
/"\ Bernd Felsche - Innovative Reckoning, Perth, Western Australia
\ /  ASCII ribbon campaign | I'm a .signature virus!
 X   against HTML mail     | Copy me into your ~/.signature
/ \  and postings          | to help me spread!

----- Original Message ----- 

From: "Bernd Felsche" <bernie@innovative.iinet.net.au>

> 
> These are the Patents which Microsoft cite further down the page.
> I've take the liberty of providing the dates and the titles of the
> Patents, as per www.uspto.gov
> 
> 5,579,517 November 26, 1996
> Common name space for long and short filenames
> 
> 5,745,902 April 28, 1998 
> Method and system for accessing a file using file names
> having different file name formats
> 
> 5,758,352 May 26, 1998 
> Common name space for long and short filenames
> 
> 6,286,013 September 4, 2001 
> Method and system for providing a common name space for long
> and short file names in an operating system


Would this mean that as I'm using only short names in the FAT filesystems
in my MP3 players, I'm not affected by this ?
Anyway, at $0.25 per unit, they wouldn't get much more than enough for 
a few cups of coffee ;-)

/Jesper

On Sat, Dec 06, 2003 at 02:15:16AM +0100, Jesper Hansen wrote:
> ----- Original Message ----- 
> From: "Bernd Felsche" <bernie@innovative.iinet.net.au>

> > These are the Patents which Microsoft cite further down the page.
> > I've take the liberty of providing the dates and the titles of the
> > Patents, as per www.uspto.gov
> > 
> > 5,579,517 November 26, 1996
> > Common name space for long and short filenames
> > 
> > 5,745,902 April 28, 1998 
> > Method and system for accessing a file using file names
> > having different file name formats
> > 
> > 5,758,352 May 26, 1998 
> > Common name space for long and short filenames
> > 
> > 6,286,013 September 4, 2001 
> > Method and system for providing a common name space for long
> > and short file names in an operating system

> Would this mean that as I'm using only short names in the FAT
> filesystems in my MP3 players, I'm not affected by this ?

That would seem to be the case. I've not studied the Patents in
detail; but they appear to be related solely to long filenames as
the first appeared in Win95. It's interesting to initially follow up
on the refernce Patents that go back to AT&T and G.E.

> Anyway, at $0.25 per unit, they wouldn't get much more than enough for 
> a few cups of coffee ;-)

For every Microsoft minion. Maximum claim against any drive
manufacturer is USD$250,000.

High time for manufacturers to adopt an unencumbered filesystem
(e.g. ext2)

-- 
/"\ Bernd Felsche - Innovative Reckoning, Perth, Western Australia
\ /  ASCII ribbon campaign | I'm a .signature virus!
 X   against HTML mail     | Copy me into your ~/.signature
/ \  and postings          | to help me spread!

RS485 bus connected devices share two cable (A,B), and
they communicate in a half-duplex manner, which means
while a slave or the master talks the others should
listen. You use a 75LS176 or equivalent RS485
transceiver ic with each slave. This IC contains a
receiver and transmitter, and you select which one is
active with the direction signal. the IC outputs the
A,B signals and you connect this outputs to a two
cable bus. The data is transferred as the voltage
difference between A, B and this brings great noise
immunity, since the aritmetic (A+noise)-(B+noise)
results in noise cancellation at microcontroller
datarates (100kbps) you can have a 1km bus.For more
information make a google search. I can provide you a
very efficient c source code if you need further help.

Murat Karadeniz



--- ckbanner <kcbanner@inbox.lv> wrote:
> HOw do I connect more than one mega8 slave to one
> master? I know rX
> and TX, but what do you mean by direction pin?  I
> thought serial prot
> was for connecting two micros together.  What do you
> mean by onboard
> comm?  
> 
> Thanks for the fast reply!
> 
> -Kc
> 
> 
> 
> --- In AVR-Chat@yahoogroups.com, MuRaT KaRaDeNiZ
> <karademu@y...> wrote:
> > mega8 has serial port, why not use RS485
> communication
> > bus. Single Master, multiple slaves (32 directly
> > supported, 128 possible with better driver ic's),
> > minimal IO requirements (TX,RX,direction pin). One
> > question however, are you doing onboard comm.?
> > 
> > Murat Karadeniz
> > 
> > 
> > 
> > --- ckbanner <kcbanner@i...> wrote:
> > > Hello,
> > > 
> > > I am doing a project where I need multiple mega8
> > > avrs sending sensor
> > > data to another controller.  The other
> controller is
> > > an OOPic-R.  The
> > > OOPic has built in functions for SPI, i2c(twi),
> and
> > > serial
> > > communications.  What is best for a multiple
> slave,
> > > single master
> > > system?  I can make code for the OOPic, but need
> > > some slave code for
> > > the avrs.  I am using Codevision and the help
> file
> > > doesn't have that
> > > much information about how to use i2c or SPI in
> > > slave mode.
> > > 
> > > Thanks,
> > > Kc
> > > 
> > > 
> > 
> > 
> > __________________________________
> > Do you Yahoo!?
> > Free Pop-Up Blocker - Get it now
> > http://companion.yahoo.com/
> 
> 


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How about the old DOS program "Golden Retriever?"  It would seem that 
would blow their claim out of the water.

REB

Bernd Felsche wrote:

>On Sat, Dec 06, 2003 at 02:15:16AM +0100, Jesper Hansen wrote:
>  
>
>>----- Original Message ----- 
>>From: "Bernd Felsche" <bernie@innovative.iinet.net.au>
>>    
>>
>
>  
>
>>>These are the Patents which Microsoft cite further down the page.
>>>I've take the liberty of providing the dates and the titles of the
>>>Patents, as per www.uspto.gov
>>>
>>>5,579,517 November 26, 1996
>>>Common name space for long and short filenames
>>>
>>>5,745,902 April 28, 1998 
>>>Method and system for accessing a file using file names
>>>having different file name formats
>>>
>>>5,758,352 May 26, 1998 
>>>Common name space for long and short filenames
>>>
>>>6,286,013 September 4, 2001 
>>>Method and system for providing a common name space for long
>>>and short file names in an operating system
>>>      
>>>
>
>  
>
>>Would this mean that as I'm using only short names in the FAT
>>filesystems in my MP3 players, I'm not affected by this ?
>>    
>>
>
>That would seem to be the case. I've not studied the Patents in
>detail; but they appear to be related solely to long filenames as
>the first appeared in Win95. It's interesting to initially follow up
>on the refernce Patents that go back to AT&T and G.E.
>
>  
>
>>Anyway, at $0.25 per unit, they wouldn't get much more than enough for 
>>a few cups of coffee ;-)
>>    
>>
>
>For every Microsoft minion. Maximum claim against any drive
>manufacturer is USD$250,000.
>
>High time for manufacturers to adopt an unencumbered filesystem
>(e.g. ext2)
>  
>