Hardware 1wire

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Hi,

is Atmel producing any controllers with hardware 1wire support? I found AVR318 app note - it shows how to use USART + transistors for hardware solution, but I'd prefer chip that is able to handle 1wire without external components.

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No. I guess they can't either as One-wire is a propriety and legally protected system of Dallas/Maxim; a license would be probably cost quite some money.

On the other hand, transistors are very cheap and if you can live with polled communications you need no external components at all according to the appnote.

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Quote:

No. I guess they can't either as One-wire is a propriety and legally protected system of Dallas/Maxim; a license would be probably cost quite some money.

Not sure about that. See I2C, it's a propriety of Philips. Atmel just change the name and we got two wire interface. Why not to remove one wire? :-)

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True, but I2C is used way more often with a lot of ICs that use it, while 1-wire is a bit of an exotic beast.

Apart from the licensing issues, Atmel decided it's not worth it; I2C gives an marketing advantage, likely bigger then 1-wire.

IIRC Dallas has 8051's with a dedicated 1-wire interface.

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mogor wrote:
Hi,

is Atmel producing any controllers with hardware 1wire support? I found AVR318 app note - it shows how to use USART + transistors for hardware solution, but I'd prefer chip that is able to handle 1wire without external components.

Put this in a "tiny" & you have an ATMEL w. 1-wire support.

http://www.mikrocontroller.net/a...

http://www.mikrocontroller.net/t...

Btw: Danni's creation

/Bingo

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Readind from DS 1990 uses only 1 4.7k resistor.Reading from DS 18B20 uses 4.7K resistor from a port and another one port of microcontroller driving a transistor for more current supply during conversions.I think this would be quite difficult without external components,otherwise a dedicated hardware inside micro must be used.