Connecting and working with Mega +WiFi R3 ATmega2560+ESP8266 (32Mb memory)

Development Tools IDE 1.x
81

gabrielcsapo:
2. Yes I am aware I was more interested in the source as the direct firmware download has changed looking through articles.

AT fw wasn't available for download separately some years ago, but now the AT section on the Espressif's site is the right download location.

EDIT:
if the esp8266 flash has only DIO then it usually supports 80 MHz access. 80 MHz DIO is faster then 40MHz QIO

82

gabrielcsapo:
Hey everyone! I have been reading through forums trying to figure out how to get the latest AT firmware on this chip! I got a lot of useful information reading through a bunch of threads and just wanted to give back as I compiled as much as I could in a blog post. https://blog.gabrielcsapo.com/arduino-web-server-mega-2560-r3-built-in-esp8266/ Let me know if I am missing anything, since I got this working I am excited to write more about it.

Compliments on the site and the instructions. Very useful. So I followed the steps according to you instructions but I got stalled after flashing the firmware. No error messages etc, changed the switches so I can use the serial monitor. Kind of looks like the serial monitor gets overloaded. There is a lot of activity on the onboard leds. The output in the serial monitor doesn’t make sense and after a few second the whole system freezes.
Any suggestions where to look? Wrong firmware?

Thx

83

menkepie:
Compliments on the site and the instructions. Very useful. So I followed the steps according to you instructions but I got stalled after flashing the firmware. No error messages etc, changed the switches so I can use the serial monitor. Kind of looks like the serial monitor gets overloaded. There is a lot of activity on the onboard leds. The output in the serial monitor doesn’t make sense and after a few second the whole system freezes.
Any suggestions where to look? Wrong firmware?

Thx

Couple questions:

  1. What is the baudrate in the serial monitor?
  2. What position in the serial monitor switch in? TX0 or TX3?
  3. Have you tried flashing more than once? For one of the boards on the first flash it was displaying similar symptoms you are describing but after the second flash it was fully functional.
84

gabrielcsapo:
Hello Juraj!

Thank you for the reply.

  1. I was unable to get the esptool to properly detect settings for me (I am using a Mac, not sure if that is the case)
  2. I tested qio, its write performance were worse for me and also upon trying to connect the esp8266 to the serial monitor I was unable to do so and saw in another buadrate that there was an infinite boot. (I flashed 3 different boards all the same problem)

Thank for the edits.

  1. I updated that, that was my bad :confused:
  2. Yes I am aware I was more interested in the source as the direct firmware download has changed looking through articles.
  3. Yes it was just easier to do both the special switch configuration and the serial1/3 settings at the same time when writing the steps down.
  4. I updated the article to include the durability of the dip switches in the beginning

Thank you so much for your edits and your work on WiFiEspAT!

is the tutorial updated?

you have -ff 20m

you didn't move WiFi.begin after WL_NO_MODULE check

and remove the comment "waiting for connection to Wifi network set with the SetupWiFiConnection sketch", because t is not true

you instruct to turn off 3,4 after upload to Mega. it doesn't make sense

85

gabrielcsapo:
Couple questions:

  1. What is the baudrate in the serial monitor?
  2. What position in the serial monitor switch in? TX0 or TX3?
  3. Have you tried flashing more than once? For one of the boards on the first flash it was displaying similar symptoms you are describing but after the second flash it was fully functional.
  1. Started at 115200 but tried all of them available
  2. TX3
  3. Several times (3)
86

Juraj:
is the tutorial updated?

you have -ff 20m

you didn't move WiFi.begin after WL_NO_MODULE check

and remove the comment "waiting for connection to Wifi network set with the SetupWiFiConnection sketch", because t is not true

you instruct to turn off 3,4 after upload to Mega. it doesn't make sense

Updated to include those changes.

menkepie:

  1. Started at 115200 but tried all of them available
  2. TX3
  3. Several times (3)
  1. It is for sure 115200 which should have the output
  2. TX0 is what I have when communicating with the esp8266, switching to that might remedy the issue.

When you are trying to connect to the esp8266 via the serial monitor can post a picture of the dip switches?

87

gabrielcsapo:
Updated to include those changes.

  1. It is for sure 115200 which should have the output
  2. TX0 is what I have when communicating with the esp8266, switching to that might remedy the issue.

When you are trying to connect to the esp8266 via the serial monitor can post a picture of the dip switches?

RX/TX0/3 switch doesn't matter, if 3,4 are off

88

gabrielcsapo:
Updated to include those changes.

still after testing the AT firmware you instruct to switch only 3,4. but at this point the final switch configuration can be set

some additional info:
the MODE button is same as switch 7, but it must be pushed while connecting power to the board. (it is connected to io 0 of esp8266. io 0 LOW at boot makes the bootloader to go in flashing mode)

89

No change of behavior after switching to TX0
Board settings: for some reason I can’t upload a picture so trying to describe:
Switch on TX0

Dipswitch:
1,2,3,4 off
5,6 on
7, 8 off

Led’s:
L and the one below/beside RX blinking red
ON green

Jumpers:
All open

90

Juraj:
still after testing the AT firmware you instruct to switch only 3,4. but at this point the final switch configuration can be set

some additional info:
the MODE button is same as switch 7, but it must be pushed while connecting power to the board. (it is connected to io 0 of esp8266. io 0 LOW at boot makes the bootloader to go in flashing mode)

Hello Juraj,

I consistently get avrdude issues when I have switches on for 1,2,3,4 when trying to upload my program. That is why I am suggesting on to switch to 3,4.

I added a section before flashing the esp8266 to disconnect it and press the mode button.

menkepie:
No change of behavior after switching to TX0
Board settings: for some reason I can’t upload a picture so trying to describe:
Switch on TX0

Dipswitch:
1,2,3,4 off
5,6 on
7, 8 off

Led’s:
L and the one below/beside RX blinking red
ON green

Jumpers:
All open

I have added additional instructions that describes how to put the esp8266 into flashing mode as Juraj describes. Could you try to do that?

One more thing, I put this in the article but maybe I should stress the importance. When you finish flashing, make sure to disconnect the arduino and switch the dip switches and then reconnect. I was having similar random characters and boot loops if I tried switch the dip switches and just hit the reset button.

91

gabrielcsapo:
Hello Juraj,

I consistently get avrdude issues when I have switches on for 1,2,3,4 when trying to upload my program. That is why I am suggesting on to switch to 3,4.

with RX/TX switch on 3?
the dip switch will fall apart if you have to switch it for every upload.

gabrielcsapo:
I added a section before flashing the esp8266 to disconnect it and press the mode button.

sorry, I meant that only as information for you. for multiple attempts to upload the AT firmware the switch 7 is a better option in the tutorial. on this board the esptool can reset the esp8266 over auto-reset circuit, but it can't set the esp8266 into flashing mode (io 0 LOW at reset)

92

gabrielcsapo:
Hello Juraj,

I consistently get avrdude issues when I have switches on for 1,2,3,4 when trying to upload my program. That is why I am suggesting on to switch to 3,4.

I added a section before flashing the esp8266 to disconnect it and press the mode button.

I have added additional instructions that describes how to put the esp8266 into flashing mode as Juraj describes. Could you try to do that?

One more thing, I put this in the article but maybe I should stress the importance. When you finish flashing, make sure to disconnect the arduino and switch the dip switches and then reconnect. I was having similar random characters and boot loops if I tried switch the dip switches and just hit the reset button.

Same story. Tried it several times. Even flashing older versions 1.4&1.6 no change at all. Looking at the serial monitor I keep feeling it’s a baudrate mismatch.

93

menkepie:
Same story. Tried it several times. Even flashing older versions 1.4&1.6 no change at all. Looking at the serial monitor I keep feeling it’s a baudrate mismatch.

what same story? how is AT version related to upload from IDE to the ATmega?

esp8266 can output 'garbage' at boot. it is normal. it is the bootloog but at different baudrate. don't care about it. if the AT firmware starts it runs on 115200 baud

but you should not see the output of the AT firmware if you switch 1,2,3,4 ON 5,6,7 OFF and the RX0/TX0//RX3/TX3 switch to RX3/TX3

94

Juraj:
what same story? how is AT version related to upload from IDE to the ATmega?

esp8266 can output 'garbage' at boot. it is normal. it is the bootloog but at different baudrate. don't care about it. if the AT firmware starts it runs on 115200 baud

but you should not see the output of the AT firmware if you switch 1,2,3,4 ON 5,6,7 OFF and the RX0/TX0//RX3/TX3 switch to RX3/TX3

I mean with same story....if I follow the instructions according to the blog (12347 on) the serial monitor is floated with data and using AT commands in impossible.

95

If I ignore this and move one with the mega2560 and upload the script, switch the dip-switches to the final stage(according to the blog of gabriel) I get the message “communication with WiFi module failed”

96

menkepie:
If I ignore this and move one with the mega2560 and upload the script, switch the dip-switches to the final stage(according to the blog of gabriel) I get the message “communication with WiFi module failed”

so first make sure the AT firmware works. the blog had errors.
the right upload command is here

it is

esptool.py write_flash --flash_size 2MB-c1 0x0 boot_v1.7.bin 0x01000 at/1024+1024/user1.2048.new.5.bin 0x1fb000 blank.bin 0x1fc000 esp_init_data_default_v08.bin 0xfe000 blank.bin 0x1fe000 blank.bin

it is possible you will have to add
--flash_mode dio
before --flash_size

97

Hi Jura,

It workes like a charme with your instructions. Thank you for that! Webserver is in the air I can see the output on the ip adres. Serialmonitor doesn’t create output but for me not an issue at all.

Thx
Men

98

menkepie:
Hi Jura,

It workes like a charme with your instructions. Thank you for that! Webserver is in the air I can see the output on the ip adres. Serialmonitor doesn’t create output but for me not an issue at all.

Thx
Men

you use Serial for comm to esp8266? use Serial3. there is a switch labeled RX1/TX1//RX3/TX3 on the board. set it to RX3/TX3 and in code use Serial3 for WiFi

99

Thx M8.

100

I have updated the article to reflect the correct flash command. https://blog.gabrielcsapo.com/arduino-web-server-mega-2560-r3-built-in-esp8266/