ESP8266 Community Forum

A serial connection between a FTDI serial board and ESP8266 does not respond to AT+ commands. The serial board is working (hardware is tested and ok), the ESP8266 does respond when the reset button is pressed (74880baud):
ets Jan 8 2013,rst cause:2, boot mode:(1,7)
But that is all; no further response to any AT command.
I tried to upload new firmware (v0.90.2.2) using ESP8266 Download Tool v3.4.9.2; I use AccessPort v1.37 as serial monitor: flashing
All wiring is done according to https://www.instructables.com/id/Gettin ... 66-ESP-12/
On the scope I can see data coming in on the RX pin of the ESP8266, and the only time there is any output is when the reset button is pressed (see above).
Flashing command window says: WindowsError: [Error 5] Access denied: 'c:\\Program Files (x86)\\FLASH_DOWNLOAD_TOOLS_V3.4.9.2\\bin_tmp'

What should best be done now to start getting this resolved?

In a new trial I used a virgin ESP8266 ESP12-F with wiring as in the drawing here attached. The same wiring principle was used for the Node MCU board used in my first post. A separate 3.3V power supply is used.

The only reply I receive (74880 baud again) is when a reset is performed or when 3.3V is applid to Vcc:

ets Jan 8 2013,rst cause:2, boot mode:(1,7)

What is wrong with my setup?

This morning I tried to communicate USB-serial (ftdi chip), same wiring as before except I left GPI0 open.
Response in Putty after startup:


ets Jan 8 2013,rst cause:2, boot mode:(3,0)

load 0x40100000, len 1856, room 16
tail 0
chksum 0x63
load 0x3ffe8000, len 776, room 8
tail 0
chksum 0x02
load 0x3ffe8310, len 552, room 8
tail 0
chksum 0x79
csum 0x79

2nd boot version : 1.5
SPI Speed : 40MHz
SPI Mode : DIO
SPI Flash Size & Map: 32Mbit(512KB+512KB)
jump to run user1 @ 1000

rf[112] : 03
rf[113] : 00
rf[114] : 01

SDK ver: 1.5.4(baaeaebb) compiled @ May 17 2016 19:23:54
phy ver: 972, pp ver: 10.1

mode : softAP(5e:cf:7f:da:6f:13)
add if1
dhcp server start:(ip:192.168.4.1,mask:255.255.255.0,gw:192.168.4.1)
bcn 100
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▒UT▒%▒▒▒uT
▒▒▒▒I▒UE▒▒▒TT▒U▒▒UU(ZUUR▒▒*U*▒*U*▒QTj*PkP▒Vխ▒▒▒QE▒rf[112] : 03
rf[113] : 00
rf[114] : 01

SDK ver: 1.5.4(baaeaebb) compiled @ May 17 2016 19:23:54
phy ver: 972, pp ver: 10.1

▒▒▒R▒U▒
▒▒▒▒▒▒.E▒B*KV▒▒ԪTWT

I finally got something working.

First the ESP8266 ESP12-F:
- found out communication works if GPIO0 is left floating and GPIO15 to GND and GPIO0, CH_PD to 3.3V.
- remainder of responses: see my previous post. Basically I think what it said is that the ESP12-F has an AT+GMRAT version:1.1.0.0(May 11 2016). Also some other text (see previous post) of which I understand nothing.
- using AT+UART? it responded with 115200; I the issued the command AT+UART=9600,8,1,0,3
Response= ok
- since then no meaningfull comms anymore, not on 9600 nor any other speed
- next step: reflash with different firmware. Any suggestiosn please?

Then the Node MCU v1.0:
- used the same wiring (SPI_CS2 floating, CH_PD and GPIO2 to 3.3V)
- no communications
- when put in flash mode (GPIO0 or SPI_CS2 to GND) some text:
ets Jan 8 2013,rst cause:1, boot mode:(3,0)
- then I tried to flash, succesfully: v0.9.2.2 AT Firmware.bin
- since then I get responses; but AT+UART does not work, I have to use AT+CIOBAUD etc, the other commands still to find out.
- UART speed: 9600, which is about actually what I want: using software serial when connected to Arduino Uno I have to keep speeds below 56000 baud, so 38400 is the best I can use on ESP8266.

Further questions:
1. Where can I download the most recent reliable original firmware for A. the Node MCU v1.0 and B. for ESP12-F units?
2. Is there some manual available because I would not know how to flash multiple files and use the correct memory allocations
3. Is there a difference in AT commands between firmware issues, and if so, where do I find documentation on that?
4. Is it true that the firmware gets thrashed when using the Arduino IDE to download software (incl bootloader), and if so what are the consequences/inconveniences/advantages/disadvantages/... ?
5. What is the most convenient non-Arduino IDE to write/compile/download software into the ESP8266?

Thanks for any responses!
Erik