ESP8266 Community Forum

- Sat Oct 29, 2016 9:07 am #57330 Hi All,

I'm new to both these forums and ESP development so please be gentle.

Following some of the guides, I've hooked up an ESP-03 module to a custom circuit board. I've ensured that the CH_PD pin is pulled up to 3V3 and I've ensured that GPIO15 is pulled down to GND. When I initially powered up the circuit board, I noticed that the current was a little excessive - 210mA from a bench supply set to 3.3V.

I connected my FTDI USB-to-TTL converter up to the ESP-03 (there's nothing else on the circuit board at the moment, just the ESP) and connected to it using Hyperterminal. When I powered the unit up, all I got was garbage coming out of it. I went one step further and hooked up my little logic analyser to the TX and RX on the ESP-03 and it would appear that the baud rate of the device is somewhere around 74800baud - odd.

Putty allowed me to set a custom baud rate so at 74800, I checked that I was actually getting something out of the ESP-03. This is the output I got:

Code: Select allets Jan 8 2013,rst cause:1, boot mode:(3,2)
load 0x40100000, len 1396, room 16
tail 4
chksum 0x89
load 0x3ffe8000, len 776, room 4
tail 4
chksum 0xe8
load 0x3ffe8308, len 540, room 4
tail 8
chksum 0xc0
csum 0xc0

2nd boot version : 1.4(b1)
    SPI Speed : 40Mhz
    SPI Mode : DIO
    SPI Flash Size & Map : 8MBit (512KB+512KB)
jump to run user1 @ 1000


I have tried other ESP-03 modules - some work perfectly, some have this very same issue. I've read some of the tutorials regarding updating firmware and I've got all the relevant utilities to do it (taken from the Updating-ESP8266-Firmware article on the mbed website and from Instructables).

The main issue I'm having is that the firmware update tools just can't communicate with the ESP-03.

Could anyone please offer any suggestions to the above?

Thank you in advance.

- Sat Oct 29, 2016 12:37 pm #57349 A bit of additional information...

Since posting the message, I've downloaded the XTCOM_Util flasher and also the ESP8266Flasher utility and tried to program 4 binary files onto the ESP-03: boot_v1.1.bin, user1.bin, esp_init_data_default.bin and blank.bin at various locations.

One thing that the ESP8266Flasher allows is the selection of all 4 bin files at once, whereas the XTCOM_Util is a bit more numb.

When the ESP8266Flasher tool reports that its finished programming, a power cycle comes back with almost identical information as posted initially but with a much older boot version (1.1 instead of 1.4(b1)) and also differences in SPI information (4Mbit instead of 8Mbit) followed by:

Code: Select alljump to run user1
<some binary garbage>


I'm thankful that I'm getting some kind of output from the ESP-03 module but I'm a little baffled as to what is going on. Looking at the on-board flash markings, it looks like it is an 8Mbit part (25Q80A or something like that) so I'll re-try flashing but with different SPI configuration settings.

I've also hand picked 20 other boards out of my pile and all exhibit the same issues. Some have comms problems but pressing down on the ESP-03 boards seems to resolve that - albeit temporarily. I'm guessing (as reported elsewhere) that there could be some bad soldering/dry joints going on.

- Mon Oct 31, 2016 6:14 am #57427 Ok, so it would seem that this issue is very much a hardware issue.

I found some posts which suggested a 10uF capacitor be placed as close to the VCC pin of the ESP-03 module - this didn't work for me. However, there was a more fundamental problem with my setup.

Although there was only the ESP-03 module fitted on the board, there was a P channel MOSFET being used as a "power on/off" control with a 10K pull-up on the gate, keeping the power control off by default. I was pulling this down to GND as part of my test but what I never did was check that 3.3V was on the drain of the FET.

It wasn't, it was about 1.3V which was causing the ESP-03 to partly boot up but go into some weird state which consumed waaaay more current. As it turns out, the MOSFET fitted was the wrong one - one with quite high RdsON. Once this was swapped, the module worked perfectly and current consumption was normal.

I can't believe it took almost days to solve this!