Esp8266 able to hosting the web server but cannot receive Serial data

Other Hardware Home Automation
1

I am working on esp8266-01 with ch340 converter.
So I was working on a timer program and displaying it on a webpage .I uploaded it and it got uploaded .

Next the webpage was getting displayed and everything was fine but i wanted to modify the program a bit cause it was not working as per expectation .

I tried uploading again and i got cannot sync error . having worked in esp for a while i do encounter that often and am able to fix it .

But ever after trying every solution i know of i couldn't solve it .

Next i went back to normal mode and webpage is still working and esp can still transmit data to serial monitor but it was not able to receive .

I measured the voltages just after opening the serial monitor which sends a data to Rx of esp8266 ,what i found was Rx was at 5V . everything else was fine Vcc / ChPd /Tx all where at 3.3V .

So the esp was not able to receive thats why i couldn't upload new sketch onto it .

I will try some other ways in which i am able to make the Rx work again like voltage divider and using nodemcu or arduino to program .

So has anyone faced something like this before ? and what could have could something like this ?

2

how do you connect the module to computer?

3

Juraj:
how do you connect the module to computer?

I am using CH340G based USB to Serial TTL converter

4

sorry I overlooked it. and do you put the esp8266 into flashing mode before uploading the sketch?

5

Juraj:
sorry I overlooked it. and do you put the esp8266 into flashing mode before uploading the sketch?

I did , and i think it was working too cause when it was entering flash mode it was not connecting to the wifi and not hosting the webpage only for normal mode it was doing so .

6

try if esptool can access it for example to retrieve the mac address

7

Juraj:
try if esptool can access it for example to retrieve the mac address

ok will do .. i will also try using nodemcu to program and see how it goes .

8

So finally .. esptool didnt work with CP340 adapter too .. but esp still responsed when i try to program it via nodemcu ..

So probably the rx pin of CP340 has gone bad will need another esp8266-01 to test that out but for now i can keep on programming via my lua based nodemcu ..