Hi,
I know that this issue was in the past already discussed but even if I've read the forum discussions regarding this topic I've not found a solution for the particular issue I'm getting (maybe because I'm a newbie).
I'm trying to use an ESP32-CAM that I bought together with its MB that should allow for power and uploading throug a USB port. However, even if I connect the GPIO0 to GND when uploading the sketch, as suggested ,( I tried a very simple LED blinking) I always get the same error No serial data received.
Pressing the BOOT button and the EN button that ARE on the MB was of no help.
So I decided to discard the MB and to use the ESP32-CAM connected with an external FTDI adapter and in this case ,after pressing the reset button (that is the only button available for this board), I was able "apparently" to upload the sketch without any error but it simply does not work ( the led doesn't blink and a test message is not printed in the serial monitor).
So, I'm completely stuck. Why the sketch doesn't work if it's correctly uploaded ? Thanks for your help.
Hi,
The MB relies on the esp32cam being a slightly modified from standard which has a reset pin, so maybe yours does not have this (although if it was supplied with the motherboard you would assume it does).
Try holding the program button whilst you connect power to the esp32cam via its motherboard and keep it held a couple of seconds, see if it will program then?
BTW - the LED pin is 4 for the main flash led and 33 for the small one (I think on the underside of the board)
Hi,
sorry for my long delay in answering your suggestion but I preferred to read more info on this issue that was debated in several forum discussions ( with contrasting results, someone saying that he was able to upload sketches only by using FTDI, someone else only with the dedicated MB).
Furthermore I've tried all the different solutions suggested in the various discussions and at the end I was able to consistently upload a sketch ( just a LED blinking with a text message iprinted in the serial monitor).
The sequence of steps that worked for me is the following one:
- use a FTDI adapter connecting its VCC to 5V pin of the board and connecting its GND with the >GND pin close to 5V pin of the board ( in some forum discussions only this pin is judged a "reliable" GND)
- use a jumper to connect GND and GPI0 of the board ( it will be disconnected after succesful uploading)
- poweron the board
- upload the sketch
- when uploaded ,disconnect the jumper between GND and GPI0
- press RST button of the board
and voila the sketch seems to work correctly.
For an old (74) newbie as I am this sequence seems disproportionately awkward but it the only that works in my hands.
Still I have the problem of using the ESP32-CAM connected with the MB that was sold together... Every effort I made was useless
Do you have any idea for this last topic ?
Thanks for your patience
Hi,
as I told you in my previous answer I was able to upload a simple cketch on esp32cam but now I've found that also camerawebservver works fine. So, probably at the present the issue seems solved in a satisfactory way.
One other thing worth investigating is if the esp32cam is not getting a good 5v power supply as they tend to be very fussy about power and can do all sorts of weird things if this is the issue.
Maybe try different usb cables (short and or thicker wires best) or a different computer?
Other thing worth trying is add a capacitor across the 5v and gnd pins on the esp32, I tend to use something like 2000uF on all my esp projects.
Hi, thx for your suggestion.
I'll try a capacitor between 5V and gnd pins but I have a doubt: do you mean that I have to try this between the pins of the ESp32cam WITHOUT the MB board or between the pins of the MB connected to the ESP32-cam ?.
Sorry for the maybe a silly question but, as I told you, I'm a newbie.
Thanks
Basically just on the esp32/MB end of the wire to act as a sort or reservoir to smooth out any spikes etc..
The esp32 especially when using wifi has big spikes of power draw and if the power supply or wire is not up to it this can result in the voltage dropping too much.
Several times I have wasted many hours chasing some weird problem only to eventually discover it is just the power supply. I am always saying this on here but then still manage to fall for it myself again - lol