Re: TI-H: TI <--?--> I2C

To: ti-hardware@lists.ticalc.org
Subject: Re: TI-H: TI <--?--> I2C
From: kaus <kaus@cybrzn.com>
Date: Sat, 17 Oct 1998 11:14:28 -0500
Delivered-To: ti-hardware-outgoing@towerguard.unix.edu.sollentuna.se
In-Reply-To: <003201bdf9e6$59d3f7e0$a0d4fea9@eddie>
Reply-To: ti-hardware@lists.ticalc.org


all the connectors are conneted to a set of common connecting connectors :))

each 2.5mm plug has three lines, which the I2C defines as SDA (data) SCL
(clock) and GND (ground).  

/SCL---+		\
|	|		|
{SDA-----+		}This is one 2.5 mm connector
|	| |		|
\GND-------+		/
	| | |
/SCL---+ | |		\
|	| | |		|
{SDA-----+ |		}This is one 2.5 mm connector
|	| | |		|
\GND-------+		/
       | | |
/SCL---+ | |		\
|	| | |		|
{SDA-----+ |		}This is one 2.5 mm connector
|	| | |		|
\GND-------+		/
	| | |
/SCL---+ | |		\
|	  | |		|
{SDA-----+ |		}This is one 2.5 mm connector
|	    |		|
\GND-------+		/

	^ ^ ^
	| | |
SCL----+ | |
line	  | |
SDA------+ +----GND line
line

So you connect as many 2.5mm connectors as you need to the 3line bus, and
when you start the applications on the calculators, a unique address is
found for each calculator.




At 10:53 AM 10/17/98 -0500, you wrote:
>
>So then how are TI-calcs networked if there is no MBus hub?  I understand
>the MBus/I2C thing now, but I still don't get how people told me that it was
>a network if there is no hub for it...
>
>-Miles Raymond
>
>-----Original Message-----
>From: kaus <kaus@cybrzn.com>
>To: ti-hardware@lists.ticalc.org <ti-hardware@lists.ticalc.org>
>Date: Saturday, October 17, 1998 10:53 AM
>Subject: Re: TI-H: TI <--?--> I2C
>
>
>>
>>Go to www.clinet.fi/~ozone/i2c for information on the Mbus and I2C systems.
>> Grant is right in that you only can legally use the I2C protocol if you
>>have a I2C device made by Phillips in the network.  However, its not likely
>>that Phillips is going to come to your house and investigate your
>>calculaotr for fear that it may use the I2C protocol.
>>
>>Back to your initial question, yes, two calculators using a ti-cable can
>>use the i2c protocol. When grant said there was no MBus, he meant that
>>there was no MBus protocol.  While this is not entirely true (Osma did
>>modify the I2C protocol slightly to better accomadate a calculator
>>network), the MBus system is more like a bunch of routines which enable you
>>to use the I2C protocol from your calculator over the link port.
>>
>>Jonathan Kaus
>>
>>At 10:19 PM 10/16/98 -0800, you wrote:
>>>There is no MBus.  Under the restrictions made by Philips the standard
>must
>>>be called 'I2C' and have atleast one authorized I2C device on the network,
>>>none of which include a TI calculator.
>>>
>>>You can use the I2C bus routines on your calculator only if you have a
>real
>>>I2C device on the network.
>>>
>>>The SDA and SDC lines are all connected in parallel and handshaking is
>>>accomplished similar to 10b-t ethernet, but not totally the same.  All
>>>grounds also have to be connected.
>>>
>>>Grant
>*CLIP*
>>-Jonathan Kaus
>>kaus@cybrzn.com
>>jedsmeny@hotmail.com
>>jedsmeny on IRC  (DALNet or EFNet)
>>ICQ: 15973088 (jedsmeny)
>>AIM: Jedsmeny
>
>
-Jonathan Kaus
kaus@cybrzn.com
jedsmeny@hotmail.com
jedsmeny on IRC  (DALNet or EFNet)
ICQ: 15973088 (jedsmeny)
AIM: Jedsmeny

Follow-Ups:

Re: TI-H: TI <--?--> I2C

From: Grant Stockly <gussie@alaska.net>

References:

Re: TI-H: TI <--?--> I2C

From: "Miles Raymond" <m_rayman@bigfoot.com>