Any advice for non RA I2C devices?

Request new hardware or ideas for the controller
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dcartier
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Any advice for non RA I2C devices?

Post by dcartier »

Are there any rules or advice about using non RA I2C devices? I needed a whack of PWM outputs so I have a couple of 16 channel PWM modules on the way. They can use a 5V I2C bus so I would expect that they should work (provided with the right custom code of course)?

I am also working on a DIY I2C dosing pump, so I guess an I2C hub is in my future.

Dennis
rimai
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Re: Any advice for non RA I2C devices?

Post by rimai »

Yes, I2C is 5V and you should be ok.
Roberto.
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DrewPalmer04
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Re: Any advice for non RA I2C devices?

Post by DrewPalmer04 »

Any reason Roberto you use I2C and not SPI? I'll be playing with master slave relationships soon.
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rimai
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Re: Any advice for non RA I2C devices?

Post by rimai »

SPI uses at least 3 wires.
Roberto.
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DrewPalmer04
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Re: Any advice for non RA I2C devices?

Post by DrewPalmer04 »

Correct. But would you consider SPI easier to select the slave based on the SS pin versus the device address needed for I2C? Just trying to figure out which I'd like to use.
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rimai
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Re: Any advice for non RA I2C devices?

Post by rimai »

You need one chip select wire per device. If you can afford bringing wires out you can go with SPI.
Just keep in mind that each chip select will use up one output pin out of your mcu.
Roberto.
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DrewPalmer04
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Re: Any advice for non RA I2C devices?

Post by DrewPalmer04 »

Any way to interface with the RA via SPI?
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rimai
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Re: Any advice for non RA I2C devices?

Post by rimai »

Open head unit and you will see the ICSP programming header. Those are SPI headers.
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DrewPalmer04
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Re: Any advice for non RA I2C devices?

Post by DrewPalmer04 »

Oh nice. Never looked for them before. Thanks.

Pinout on the eagle?
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