SV: [basicstamps] One Wire
Archiver
Posts: 46,084
Greetings!
The 30 seconds run down:
The 1-wire network is a strict master/slave network that only needs
1 IO pin(hence the name) and which allows you to have literally hundreds of
chips connected, while still being able to control them individually.(By use
of the 64bit serial numbers)
Chips in my collection are:
1-Wire 'serial numbers' - Just that. No functions on them. Only the
possibility of finding them...
DS2406/2407 switches. Comes in either TO-92 or 6pin SOIC pacakges and have
either 1 or 2 IO pins
(Pin one can sink/source about 50mA at up to 12V, while pin 2 does
up to 8mA)
There's a lot of NV-RAM,
EPROM(One time Programmable),
some EEPROM,
temperature sensors,
DS2409 'Network switch' - This is connected across the 'bus' and splits it
into two branches. It allows you to 'shut off' one or both branches.
AD converters (4 in one, 8pin SOIC)
Digital potentiometer (256 steps from 0 to 100KOhm)
Then there's the iButtons...
(Encapsulated in steel. 16mm Diameter, 5mm thickness)
Among them can be mentioned
DS1996 - 8KB NV-RAM
DS1921 - 'Thermochron' - Real fun. It can be programmed to take temperature
readings at intervals(from 1 to 255 minutes) and store up to 2048 such
readings. This has a small lithium cell inside that's supposed to last about
10 years...
'Secure iButton'... You can't get to the contents without knowing the
password...
Java iButton. - Runs Java programs. May for example be used as a
'co-processor' or advanced data storage... (client/server database for
example)
As for limits to the chain...
Well...
You can have a LOT of these chips on one line if you just remember a few
simple rules...
1. NEVER command a whole lot of temperature sensors to do a reading at one
time (They draws much more power than usual just then)
2. Use good quality cable. (Capacitance and signal distortion can be a
problem over long distances if there's many chips on the line)
3. 'Star configurations' aren't too good. A single line is best.
(If you need a 'star' either use separate IO pins or use DS2409's )
4. Avoid having the cable next to power lines...
5. Read the 1-wire standards document...
:-)
Trygve
Opprinnelig melding
Fra: Jeremy Arntz [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=8FeU1gK4YihInlqPrYnIUvC54B1cwPkBZ-7aJ5Yaayk_SsVlJrS7z70_iJZeJklo3Rt6Q1lj1PecKs4acCU]jeremy@u...[/url
Sendt: 13. juni 2002 00:25
Til: basicstamps@yahoogroups.com
Emne: [noparse][[/noparse]basicstamps] One Wire
Can someone give me the 30 sec run down on exactly
what one wire is?
From what I understand its a way to have many i/o
"circuits" on one line and they all have seperated
addresses. What kinds of things are available for 1 wire?
and is there any limit to the chain?
is this correct?
thanks,
Jeremy
To UNSUBSCRIBE, just send mail to:
basicstamps-unsubscribe@yahoogroups.com
from the same email address that you subscribed. Text in the Subject and
Body of the message will be ignored.
Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
The 30 seconds run down:
The 1-wire network is a strict master/slave network that only needs
1 IO pin(hence the name) and which allows you to have literally hundreds of
chips connected, while still being able to control them individually.(By use
of the 64bit serial numbers)
Chips in my collection are:
1-Wire 'serial numbers' - Just that. No functions on them. Only the
possibility of finding them...
DS2406/2407 switches. Comes in either TO-92 or 6pin SOIC pacakges and have
either 1 or 2 IO pins
(Pin one can sink/source about 50mA at up to 12V, while pin 2 does
up to 8mA)
There's a lot of NV-RAM,
EPROM(One time Programmable),
some EEPROM,
temperature sensors,
DS2409 'Network switch' - This is connected across the 'bus' and splits it
into two branches. It allows you to 'shut off' one or both branches.
AD converters (4 in one, 8pin SOIC)
Digital potentiometer (256 steps from 0 to 100KOhm)
Then there's the iButtons...
(Encapsulated in steel. 16mm Diameter, 5mm thickness)
Among them can be mentioned
DS1996 - 8KB NV-RAM
DS1921 - 'Thermochron' - Real fun. It can be programmed to take temperature
readings at intervals(from 1 to 255 minutes) and store up to 2048 such
readings. This has a small lithium cell inside that's supposed to last about
10 years...
'Secure iButton'... You can't get to the contents without knowing the
password...
Java iButton. - Runs Java programs. May for example be used as a
'co-processor' or advanced data storage... (client/server database for
example)
As for limits to the chain...
Well...
You can have a LOT of these chips on one line if you just remember a few
simple rules...
1. NEVER command a whole lot of temperature sensors to do a reading at one
time (They draws much more power than usual just then)
2. Use good quality cable. (Capacitance and signal distortion can be a
problem over long distances if there's many chips on the line)
3. 'Star configurations' aren't too good. A single line is best.
(If you need a 'star' either use separate IO pins or use DS2409's )
4. Avoid having the cable next to power lines...
5. Read the 1-wire standards document...
:-)
Trygve
Opprinnelig melding
Fra: Jeremy Arntz [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=8FeU1gK4YihInlqPrYnIUvC54B1cwPkBZ-7aJ5Yaayk_SsVlJrS7z70_iJZeJklo3Rt6Q1lj1PecKs4acCU]jeremy@u...[/url
Sendt: 13. juni 2002 00:25
Til: basicstamps@yahoogroups.com
Emne: [noparse][[/noparse]basicstamps] One Wire
Can someone give me the 30 sec run down on exactly
what one wire is?
From what I understand its a way to have many i/o
"circuits" on one line and they all have seperated
addresses. What kinds of things are available for 1 wire?
and is there any limit to the chain?
is this correct?
thanks,
Jeremy
To UNSUBSCRIBE, just send mail to:
basicstamps-unsubscribe@yahoogroups.com
from the same email address that you subscribed. Text in the Subject and
Body of the message will be ignored.
Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/