i uploaded an empty Sketch to the uno and while uploading the Tx and Rx of the Arduino are flashing as well as the blue led on the Module, then with opening the Serial Monitor of the Arduino IDE and typing the "AT" command the blue led of the Module does not flash any more which means that the Module does not recieve the Serial input, after reading a lot of articles i found a lot of solutions but all of it didn't work, i just need to know the answer of these questions :
1- Should i connect the Tx of the Module to the Rx of the Arduino (insted of Tx => Tx )?
2- i knew that Uno's 3.3v does not provide enough current to power the Module, i powerd the Arduino from an external 9V 0.6A wall adapter, is that sufficent or should i power the Moudle itself externally not the Arduino ?
3- is using Tx and Rx of the Arduino should work or should i use another 2 pins to communicate with the Module using the SoftwareSerial Libray ?
thanks for your time, any help would be greatly appreciated
tx -> rx
rx -> 100 Ohm -> tx // resistor limits currents as arduino's tx is working at 5v and the esp at 3v3
vcc -> 3v3
ch_pd -> 3v3 // eps doesnt do anything without this
gnd -> gnd
the arduino can provide more than enough to feed an esp8266 @ 3v3
tx -> rx
rx -> 100 Ohm -> tx // resistor limits currents as arduino's tx is working at 5v and the esp at 3v3
vcc -> 3v3
ch_pd -> 3v3 // eps doesnt do anything without this
gnd -> gnd
the arduino can provide more than enough to feed an esp8266 @ 3v3
ok i made this connection and i bypassed the Atmega chip by connecting the Reset to GND so that the Arduino is now just a USB to Serial Converter, still dont get any response from the ESP but i can see the ESP Wi-Fi AP in the Available Wi-Fi Netwroks, i wrote "AT" and "AT\r\n" through the Arduino IDE Seria Monitor on both 9600 and 15200 baud rates ..... any guess on what i am missing ?
mFar:
ok i made this connection and i bypassed the Atmega chip by connecting the Reset to GND so that the Arduino is now just a USB to Serial Converter, still dont get any response from the ESP but i can see the ESP Wi-Fi AP in the Available Wi-Fi Netwroks, i wrote "AT" and "AT\r\n" through the Arduino IDE Seria Monitor on both 9600 and 15200 baud rates ..... any guess on what i am missing ?
thanks again
Ignoring requirement of the 3.3V power supply yet again?
ieee488:
Ignoring requirement of the 3.3V power supply yet again?
actually i don't have a 3.3V power supply and i am not experienced enough to build a cuircuit to convert my 9V supply to a 3.3V one, can i do it by a basic voltage divider?
Than wire the reset of the arduino to ground, so the atmega chip gets bypassed. Your uno board now functions as usb-ttl converter for your esp module.
You don't need/want an external 9V power supply for now. If you plug in your USB cable in the computer, you have plenty of juice to feed uno and esp.
If you done all this, you can simply open up the serial monitor of arduino IDE. It is important that in the bottem of this monitor you select newline character and return carriage NC and RC. Later when you start writing code it is important to use the println() instead of print() because println() adds these 2 chars to your string, but thats problem for later
If you have done all this, and there is an LED of the esp shining, you should be able to send AT commands. IF you type AT, the module will respond by echoing back AT followed by OK
PS it could be, but I doubt this, that as people said before the 3v3 pin of the uno might not supply enuf power. The circuit to make a 3v3 regulator is a simple one. You need one NPN transistor like a bc547, one 1k resistor and one 4V zener diode.
bask185:
You don't need/want an external 9V power supply for now. If you plug in your USB cable in the computer, you have plenty of juice to feed uno and esp.
Parameters Min Typical Max Unit
Tx802.11b, CCK 11Mbps, P OUT=+17dBm 170 mA
Tx 802.11g, OFDM 54Mbps, P OUT =+15dBm 140 mA
Tx 802.11n, MCS7, P OUT =+13dBm 120 mA
Rx 802.11b, 1024 bytes packet length , -80dBm 50 mA
Rx 802.11g, 1024 bytes packet length, -70dBm 56 mA
Rx 802.11n, 1024 bytes packet length, -65dBm 56 mA
Modem-Sleep① 15 mA
Light-Sleep② 0.9 mA
Deep-Sleep③ 10 uA
Power Off 0.5 uA
This seems to be a new usage of 'plenty' I was not aware of.
Whandall:
Arduino Uno spec:
ESP datasheet
This seems to be a new usage of 'plenty' I was not aware of.
As said mine responds to my AT commands using the onboard 3v3 regulator, I might have a clone. But the chance that he has a clone is bigger than a legit one.
If he follows my instructions and if the ESP than still does not respond, than we all know that the power supply is most likely the issue.
Than wire the reset of the arduino to ground, so the atmega chip gets bypassed. Your uno board now functions as usb-ttl converter for your esp module.
You don't need/want an external 9V power supply for now. If you plug in your USB cable in the computer, you have plenty of juice to feed uno and esp.
If you done all this, you can simply open up the serial monitor of arduino IDE. It is important that in the bottem of this monitor you select newline character and return carriage NC and RC. Later when you start writing code it is important to use the println() instead of print() because println() adds these 2 chars to your string, but thats problem for later
If you have done all this, and there is an LED of the esp shining, you should be able to send AT commands. IF you type AT, the module will respond by echoing back AT followed by OK
PS it could be, but I doubt this, that as people said before the 3v3 pin of the uno might not supply enuf power. The circuit to make a 3v3 regulator is a simple one. You need one NPN transistor like a bc547, one 1k resistor and one 4V zener diode.
now i have a 3.3v 8A power supply to feed the Module, Tied the RESET pin of the Arduino to GND and made the following Connection :
opend the Arduino IDE Serial Monitor and sent "AT" with all possible combinations of (Carriege Return-New Line- both) at baud rate 9600 and 115200 ... still no response though the blue LED on the Module is ON (not blinking)
this is the only connection to get the blue LED ON, even when i connected the voltage divider to the Rx of the Arduino it went OFF
now it is not a power issue i think it is a hopeless case .... does anyone know anything about the NodeMCU Esp8266 board ? will i just plug it and start to program without making any connections ?