Different circuit neeeded for automatic upload using CP210x

[probonopd]

[Comment shortened in order not to confuse people -- see https://github.com//issues/480#issuecomment-122993574 for the recommended circuit]

I can reliably upload using baud rate 921600.

It would be good if others could test this setup too and if it works for everyone, it could be changed in the README.

[Links2004]

the problem is the Arduino IDE or you Serial terminal.

is the boot loading still working with the 10k?
i don't think its good for the stability of the uploading.

the problem shut be fixed in software (Arduino IDE) so that DTR and RTS is not activate in our case.
i use "real term" for serial debugging there i can control DTR and RTS manually.

[probonopd]

Yes 921600 is working fine for me.

[cimba007]

I thing I have the same problem here. What are your resistor values for "pull up and pull down"?

[probonopd]

10K

[cimba007]

What are u doing with GPIO0 and RESET when the CP210x is not connected? What values are you using in this case?

[probonopd]

Good point. In my case the CP210x is always connected and is also used to provide the 3.3V (which appears to work sometimes in my case - better use the 5V from USB and a voltage regulator). I guess you'd have to put in pullups instead when the CP210x is removed.

[Links2004]

https://github.com/esp8266/Arduino/blob/esp8266-sdk-1.0/README.md#minimal-hardware-setup-for-running-only

[probonopd]

Following advice from igrr, I am now using the circuitry from the NodeMCU 0.9 for my ESP-12Es. See the schematics of the NodeMCU 0.9.

I used slightly different parts that I had lying around, two 2N2222 npn transistors and 3 10k resistors, thereof 1 pullup for CH_PD. (I think I inadvertently connected CH_PD instead of nRST; need to double check.) U2 is the CP210x in my case. Note that it cannot provide enough 3.3V current, but using a voltage regulator to convert 5V coming from USB works.

Working well (occasionally I have to press upload twice, maybe this is related to me wiring up CH_PD instead of nRST). This circuit can be used for flashing and running, it does auto-reset and the serial monitor in the IDE can be used.

I built a jig out of perfboard that holds the ESP-12E in place using the castellated pins.

This way I can flash and experiment with bare ESP-12E boards very quickly - no need to solder anything to them.

Possibly the documentation in the README should be updated to reflect this.

[JeroenBeemster]

Thanks probonopd, This solved my issue aswell.For everyone who find it hard to read electronic schematics. I created a simplified example using a breadboard explanation.
http://www.arduinesp.com/blink

[probonopd]

Thanks JeroenBeemster, I hope you are not offended if I attach your example for quick reference here.

[ReMiA00]

I have tried several methods on resetting the ESP-12E for flashing with Arduino IDE
However none worked great, and all will break the "serial monitor" in the IDE

Since i had a ATtiny85 lying around i used this to send the reset to the ESP:

• The RTS pulse on my CP2102 lasts about 5 to 8 millis
• When serial monitor is started RTS remains low until the monitor is closed.
• To reset the ESP the RST pin needs to gow LOW while keeping GPIO0 LOW while booting the ESP

/*
  Reset ESP-12E with ATTiny85 (8Mhz)
 */

#include <SoftwareSerial.h>
#define rxPin 3  
#define txPin 4

SoftwareSerial mySerial(rxPin, txPin);

const int RTS_pin = 2; // Pin 7 on Attiny
const int RST_pin = 0; // Pin 5 on Attiny
const int GPIO0_pin = 1; // Pin 6 on Attiny

// Hookup 
// ESP     <--> Tiny pin <--> CP2102 or FT232RL
//  GND   <-->  4        <--> GND
//  5V    <-->  8 
//              7        <--> RTS 
//  RST    <--> 5            
//  GPIO0 <-->  6                  
//  RX <-------------------> TX
//  TX <-------------------> RX

unsigned long StartReset = 0;
unsigned long Puls = 0; 

void setup() {
  mySerial.begin(9600);

// USB to Serial Converter Flow Control RTS
  pinMode(RTS_pin,INPUT);

// ESP Pins
  pinMode(RST_pin,OUTPUT);
  pinMode(GPIO0_pin,OUTPUT);
  digitalWrite(RST_pin, HIGH);
  digitalWrite(GPIO0_pin, HIGH);
}

void loop() {
  int RTS = digitalRead(RTS_pin);

  if (RTS == 0 and StartReset == 0 ) { // Start Reset Puls
    StartReset = millis();
    mySerial.println("Reset");
  } 
  if (RTS == 1 and StartReset > 0 ) {  // Eind Reset Puls
    Puls = millis() - StartReset;
    mySerial.print("Puls = ");
    mySerial.println(Puls);
    StartReset = 0;

    if (Puls > 0 and Puls < 20) { // puls is around 5 to 8 millis
      digitalWrite(RST_pin, LOW);
      digitalWrite(GPIO0_pin, LOW);
      delay(5);        // length Reset puls
      digitalWrite(RST_pin, HIGH);
      delay(1000);        // Wait for ESP to boot
      digitalWrite(GPIO0_pin, HIGH);
      Puls = 0;
    }  
  }
}

I used a Arduino Nano with ArduinoISP sketch to program the ATTiny using IDE 1.6.5
Add in "Boards Manager" https://raw.githubusercontent.com/damellis/attiny/ide-1.6.x-boards-manager/package_damellis_attiny_index.json (see http://highlowtech.org/?p=1695)

Wire it up:
// Hookup to Program ATTiny85
// NANO <--> Tiny pin
// GND <--> 4
// 5V <--> 8
// 10 <--> 1
// 11 <--> 5
// 12 <--> 6
// 13 <--> 7

Choose ATTiny85 Board at 8Mhz and flash the Bootloader
Now you can upload the sketch to the ATTiny (use Arduino as ISP as programmer)

Wires for Serial debugging
// NANO <--> Tiny pin
// RX(0) <--> 3 serial monitor
// TX(1) <--> 4 serial monitor