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Topic: Arduino Nano with SPI Daisy Chain (Read 1 time) previous topic - next topic

DeB86

Hi to all,
First time posting here, I need an advice on the possibility to build a daisy chain with 2 or more SPI slave devices.

The master will be the Arduino Nano, with an RF24L01+ and a ISD 1790 connected to it.
I need a daisy chain to connect them because I haven't more pins available to do a separate slave select for each device.

There is any possibility to realize a daisy chain without having the control over the devices' software?

Other solution is using an Arduino Mega and a separate slave select line for each device. ;)

Thank you in advance.
Marco

Graynomad

#1
Mar 05, 2012, 12:53 pm Last Edit: Mar 05, 2012, 01:04 pm by Graynomad Reason: 1
You can daisy-chain SPI devices under certain conditions like they are all the same and/or simple devices like shift registers and/or smart devices that can handle the data stream.

I'm not familiar with the devices you are using but I doubt it would be possible to connect them like that as they would have different requirements for the data written. Do they even have data outputs?

If you can spare a single extra pin you can use external logic to select between any number of devices by using a shift reg to provide the CS signals.

_____
Rob
Rob Gray aka the GRAYnomad www.robgray.com

DeB86

Thank you very much,
i should be able to free 2 pins to do 2 slave select channels.

Thankyou again!

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