I need 2 SPI, is it possible with arduino?

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21

Maybe i'm missing something here as I cannot see how the block diagram would work. MOSI is an output on SPI so it cannot receive whatever comes out of DATA_RX.

Can you not treat this chip as 2 devices on the same SPI bus?

The device has 2 chip select signals, one for Tx and the other for Rx. SCLK_0 & SCLK_1 could go to the micro SCK pin, MOSI_0 to MOSI, and MOSI_1 to MISO. You would have 2 chip select signals from your micro to use to determine if you were sending data to the device or receiving data from the device.

22

Thanks for your help.
It is nevertheless well specified everywhere when one inquires about the component MC33664, it is indeed necessary 2 different SPI.

In general, if I understand correctly, to use the SPI you need a master and a slave. The master's MOSI must be connected to the slave's MOSI, right?
The master sends a message via MOSI, the slave receives it via its MOSI. The slave responds through MISO, the master receives the response through MISO, right?

With the MC33664 it's different.
The MCU, as master, sends a message to the MC33664 which is slave in this case. And, to return a response, the MC33664 becomes master, sends the message (the response) to the MCU (MCU as a slave this time).

So I will need you to teach me how to send an SPI frame via MOSI (by configuring the ESP32 as master). As well as reading the incoming message in another MOSI, with the ESP32 as a slave via another SPI. Am I clear?

23

Ah, ok. I wonder if it would work if you set your Arduino up as an SPI slave (using hardware SPI) to receive data from the device and then use the ShiftOut() function in conjunction with a ChipSel for the Arduino master.

You may need to implement your own ShiftOut if the clock data phase needs changing.

24

Currently I try to use this lib:

with the example "master_slave_polling"

I understand that thanks to this example, I already have one SPI configured as a master and the other as the slave.

Now I try to adapt this to send (master to slave) my frame, which looks like:

mytrame[0]=0x3B;
mytrame[1]=0x1;
mytrame[2]=0x1;
mytrame[3]=0x0;
mytrame[4]=0x0;

but I don' t understand how to do...

And after that I try to understand how to read incoming data from the MOSI of the other SPI

25

I managed to transmit a message from the MC33664 (master in this case) to the ESP32 (slave therefore) on pin 13.
How to read this message from ESP32 side?

26

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