So, in addition to that though, there's also a chip enable.
Now chip enable is because with SPI, if you remember, there can be a master,
the single master, talking to many slaves.
But it can only talk to one slave at a time.
So it needs to assert the chip enable for the particular slave that it's talking to,
to let that slave know it is communicating,
right, that slave should wake up and listen.
So each slave has to have a chip enable associated with it that the master can
assert, can pull down, in order to wake them up and have them listen.
So in this case, in this board you get two chip enables, pins 24 and 26.
So 24 is chip enable CE0, and 26 is CE1.
And notice the N after the name, CE0_N, CE1_N.
N is for negative.
So it's negatively assertive, meaning you have to pull that wire down so
the Raspberry Pi will send that from one to zero to let the client know,
let the slave know that it is being communicated with.
So Raspberry Pi gives you two chip enabled pins.
You might need more, depending on how many SPI components are on your bus, how many
slaves you have on your bus, cuz you need a chip enabled for every single slave.
But this gives you two, which is pretty good.
I mean, I don't know how many you are gonna need, depends on the application.
So this is SPI, and SPI you've got the MOSI and MISO,
and you got two chip enables.
And again, when you actually do this, when you actually use this protocol,
you'll be using the Python library for
communication, which we will talk about later.
Thank you.
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