ESP8266 Community Forum

Posted: **Sun Mar 22, 2015 6:12 pm**

Hello all

My ESP8266-01 is connected to an External 3,3V and a FTDI Usb UART.

I connect the GPIO0 to the GND, and I succed to upload the lastest nodemcu with ESPFlasher.

I unconnect the GPIO0 from the ground, restart electrically the ESP8266 and unplug the FTDI.
Start either Esplorer or lualoader, replug both and connect COM6/9600.

If I try to send AT, or anything else, no reply.
I check the connection GND, VCC, TX, RX. Doesn't seem to have a problem.
I see the TX led on the FTDI, no bleu on ESP, and no RX on FTDI;

I tried 2 ESP8266, same phenomena.

Any idea that I made wrong?

I succeded earlier this evennig, but nothing now.

J.P from Belgium

Posted: **Mon Mar 23, 2015 7:21 am**

Hi
Try connecting your ftdi before running esplorer so that esplorer can see the com port.

Regards
Gerry

Posted: **Mon Mar 23, 2015 2:28 pm**

at least it's not a FTDI fault,

this arduino program works fine:

Code: Select all

void setup() {
  // initialize serial communication at 9600 bits per second:
  Serial.begin(9600);
}


also with Esplorer
// the loop routine runs over and over again forever:
void loop() {

  Serial.println("hello");
  delay(1000);        // delay in between reads for stability
}

Now let's plug the famous ESP8266-12 board (self alimented with 3AA).
ai-thinker

3 wires (RX, GND, TX).

Even if I'm a stupid guy, I reverse the TX/RX.

But still no response to an AT command !!!
Here, I don't see what can be wrong with 3 wires !

the ftdi is set to 3,3v

Posted: **Mon Mar 23, 2015 3:27 pm**

With Esplorer, I've to decode some esp communication @ 74880 baud.
The Esplorer is on
Port COM6 open @ 74880 baud
Power on the 3 AA:
here is the result:

1/ I'm not so stupid to connect a TX to RX and reverse (Ouff)

here is the response:

Code: Select all

PORT OPEN 74880

 ets Jan  8 2013,rst cause:2, boot mode:(3,7)

load 0x40100000, len 25408, room 16 
tail 0
chksum 0xf0
load 0x3ffe8000, len 5888, room 8 
tail 8
chksum 0x12
load 0x3ffe9700, len 11840, room 0 
tail 0
chksum 0xe4
csum 0xe4
"à�`1á„¨ç™%F�@-±   ¸äˆu®ro|‹Mk5þêQ*eèôNƒ„5‡1êS®1¥!ŠwQn„h¡«v»QÛe›s‹qI…DtZtJ
DtZôZ
„r7„ô×ht®TKk®1ƒB1Pk©%òêUÊ›S@nÖ-WlµH/-Ç1á�t|Šâ�

From this good try,
I reconnect in the same way (with an external 3,3V) the ESP8266_01 board (GPIO0 to GND)

Code: Select allets Jan 8 2013,rst cause:1, boot mode:(1,7)

and GPIO0 disconnected

Code: Select all

PORT OPEN 74880
 ets Jan  8 2013,rst cause:1, boot mode:(3,7)

load 0x40100000, len 30452, room 16 
tail 4
chksum 0xd2
load 0x3ffe8000, len 2728, room 4 
tail 4
chksum 0x2e
load 0x3ffe8ab0, len 13560, room 4 
tail 4
chksum 0x12
csum 0x12

the boot seems broken

ESP8266 Community Forum

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