Configuring ESP32 as an Oscillator (Clock Source)

Projects General Guidance
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Hello Community ! I am doing a project which Includes Daisy Chaining of 2 slaves and to one master (ESP32). To achieve proper SPI Communication We need to add 2 Chip Selects for both the slaves. For that we need a clock which is common for both the slaves. Now my Question is ,

  1. Can I Configure any GPIO pin on the esp32 board so that I can use it as an Oscillator (Clock) of 8MHZ ?
  2. Both of the slaves have the pins called clk , Can I just short those two and say that they are Synchronized (Getting the same clock pulse ) ?
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Why do you think that?

Includes Daisy Chaining of 2 slaves

What does that mean? The SPI is a bus, for devices connected in parallel.

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Your topic has been moved to a relevant category. Please be careful in future when deciding where to start new topics

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Hello jremington !
Thanks for the reply !!

Since the slave chip needs an oscillator to operate and to get connected in daisy chain mode , a common (ie; one single source providing the same clk pulses for both the slaves ) clk source is needed. This is what I meant.

Additionally , please note that we are using SCLK for the Master and Slave communication and clk for synchronizing only the 2 slaves.

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The SPI bus already has a clock signal (SCK), which is common to all devices.

Please post a hand drawn schematic or block diagram of the proposed connections, and use it to explain why you think you need another clock signal.

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Okay I will now explain everything here :
We are Daisy Chaining 2 devices along with an esp32. The hardware Components is as follows (A power supply is used, But I haven't specified it in the Circuit Diagram here. ),

  1. Master -- ESP32
  2. Slave1 -- Device1
    3)Slave 2 -- Device 2

Now the Din , Dout , SCLK, CS1(Slave1) ,CS2 (Slave2) is the SPI Interface pins used by ESP32 and its slaves to communicate. (Which can be seen in the Block Diagram).

In order to read data simultaneously , the 2 slaves need to be in Sync with each other through a clock (which is specified as clk ) here.
Note that the SCLK is for the Communication of the Master and 2 Slaves but , clk is for the Synchronization of only the 2 slave together themselves.

Now my Simple Question is ;
Since I need an extra clk , Will I be able to Configure any GPIO pin on the esp32 board so that I can use it as an Oscillator (Clock) of 8MHZ ?
Screenshot (205)

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Not possible. Only one digital signal, from one device, can be placed on MISO at a time.

Why do you think "Device 1" and "Device 2" need to be clock-synchronized?

If you want help with this project, you will have to do a much better job of explaining what it is that you are trying to do.

Please read and follow the instructions in the "How to get the best out of this forum" post.

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Hello @jremington I completely read the "How to get the best out if this forum" sections and now I understand how it works.

Sorry for the late reply.

Thank you for your help and assistance for my Project. I now have successfully achieved the task of synchronizing 2 devices with the Internal Clock pulse and external clock pulse to each of them and they both work perfectly fine now.

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