[moved] General questions about wifi module -esp8266

Hello World,

Can you please tell me the following basic questions directly without providing link or any other datasheets.

1) which level should wifi module ESP8266 required - TTL or RS232 level?

2) If I want to connect same module directly to PC then which USB to serial module module I would required- USB to ttl or usb to rs232? (please suggest module numbers also).

Thank You in advance. Hope you all are doing well.


Pica

Hi,

Either one of us or you needs to read the datasheeet.

I assume you have it by hand. We don't have it, and because you even didn't give us a link to it, its much more effort for us to find it, download it and read it.

So I recommend to read it yourself. The answer will be written very clearly in it.

Klaus

Dear KlausT,

Please see the below link which is a datasheet of ESP8266

**broken link removed**

Thanks in advance.waiting for your reply.

Have a great day.

Hi,

* your link was broken, i corrected it
* This is not a datasheet, but a quick start guide from un unknown source.
--> please refer to datasheets directely from the manufacturer.

**********
QUICK START GUIDE says:
"The ESP8266 needs to communicate via serial at 3.3V and does not have 5V tolerant inputs".
--> This clearely says it is LVCMOS level and no RS232 level.

**********
DATASHEET says: ()
3.1. GPIO
3.1.1. General Purpose Input/Output Interface (GPIO)
...
These pins are multiplexed with other functions such as I2C, I2S, UART, PWM, IR Remote Control, etc.
...
Table 6 Pin Definitions of GPIOs
Variables Symbol Min Max Unit
Input Low Voltage VIL: -0.3 | 0.25×VIO | V
Input High Voltage VIH: 0.75×VIO | 3.3 | V
*****
None of the papers talk about RS232 levels.

Klaus

Dear KlausT,

Can you please suggest me a USB to LVCMOS level converte. I wanted to buy for the same module ESP8266 to directly connect it to PC.

Pica

Most USB-to-UART bridges work perfectly with 3.3V level, e.g. FT232. It has an inbuilt 3.3V regulator, output drivers can be jumpered to either 5 or 3.3V level.

Well FVM... I will buy the same for my ESP8266 module. Thanks for the suggestion. Appreciated.:wink:

- - - Updated - - -

I have one more doubt. If I run a program in my microcontroller and it has a function which is for sleep mode. the question is, after running sleep function does next portion of my program will executed or not.

Let me clear the idea by one example:


Does I get the values of e,f,d or not?

Hi,

Does I get the values of e,f,d or not?

Click to expand...

Yes, it will be processed AFTER wakeup from sleep.


Klaus

While FT232 does give 3.3 volts regulated output which is required for esp8266, it does not source the required current output. ESP8266 may draw current upto 200 mA. However, FT232 gives a maximum current of 50mA.

the required current output. ESP8266 may draw current upto 200 mA. However, FT232 gives a maximum current of 50mA.

Click to expand...

answer to this

https://fab.cba.mit.edu/classes/863.14/tutorials/Programming/serialwifi.html

https://www.instructables.com/id/ESP8266-Wi-fi-module-explain-and-connection/step2/THE-FTDI232R/