How L108 CPU communicates with WIfi CPU in ESP-WROOM-02?

[ritesh]

Hi,

I am working on ESP-WROOM-02 Wifi Module and want to understand how L108 CPU communicates with WIfi CPU.

Please provide me some details or links for that.

Regards,
Ritesh Prajapati

[ESP_Sprite]

Erm.. the WROOM2 runs on an ESP8266, which only has one CPU (namely the Xtensa LX106).

[ritesh]

Hi,

But, How ESP-WROOM-02 CPU communicates with WIfi Circuit?

I want to understand that how ESP-WROOM-02 CPU handles STA and AP mode at a time and provides communication interface with devices connected with it

Regards,
Ritesh Prajapati

[prismatics]

Anyone? Is it via SPI or is it a peripheral connected via AHB? Are there registers which can be accessed, is there a DMA channel or interrupt whatsoever provided just for WiFi? Is there a possibility to get the entire packet information (including radio tap header)?

[ritesh]

Hi,

Anyone has any idea or informations about how L108 Xtensa communicates with WiFi circuit to work on both STA+AP mode into ESP-WROOM-02 WiFi module?

Please let me know if anyone has any informations for that.

Regards,
Ritesh Prajapati

[diegogonz76]

Hi, I am new in this module also, but as I understand there are three main things inside the WROOM-02, the ESP8266 that is a micrcontroller with wifi, the spi flash memory and the oscilator. No wifi only chip.

[pratik]

Hello all,

I hope I clarify things with my answer here:
The ESP-WROOM-02 is a module based on the ESP8266. The main purpose of this module is to give you a small subsystem or module that you can directly place into your applcaition without having to bother about designing a chip antenna and dealing with RF circuit design!

What does the ESP-WROOM-02 contain?
It contains the ESP8266 SoC, which contains the entire RF transceiver circuit on the silicon die. The ESP8266 chip thus has a 32-bit Xtensa core which interfaces to the on-chip WiFi block via the usual way SoC cores access peripherals (i.e. address bus, data bus, registers... etc).
The WROOM-02 also contains a flash memory chip to store the user program... and a crystal oscillator to clock the ESP8266. So there are these 2 chips and a crystal inside + some discrete cmoponents!

Can you access the WiFi peripheral using registers?
No! We provide SDK APIs and functions for that. The main code is confidential because we don't want people to be messing around with a programmable 2.4GHz radio and render all other WiFi networks in the area useless by transmitting gibberish with a buggy software!
Also, messing with the internal parameters may potentially cause permanent damage to the chip in some cases.

How is the flash connected to the ESP8266?
The flash chip inside the WROOM-02 module uses the SPI interface to connect to ESP8266.