mickeypop wrote:ESP_Angus is right.
Almost all FTDI chips can only supply 50mA, so when the WiFi goes live the BROWN OUT happens.
On the FTDI there is usually a voltage select jumper 3.3V/5V.
I piggy backed a LM1117-3.3 and tied the center pin to the LM1117 output (no more jumper) and brownouts stop since the 1117 can drive around 600mA.
As to flashing;
Look at the 2 NPN, 2 resistor circuit on any USB programmable board.
The 3.3v,tx,rx,DTR are on any FTDI board output pins, however not every board brings out the RTS.
It on the chip, just connect to it.
You will need to connect it to make the auto flash work.
Just wire up any NPN pair between the FTDI and the ESP32 for the auto programming.
That is a good point. In the current rev of my board I haven't wired up DTR and RTS on the header, those go to testpoints but not to the npns like the same signals from the usb connector.
One other point is that I do have 100 ohm current limiting resistors on each signal. I don't think this should be a problem but wanted to bring it up.
Shouldn't I be able to program without DTR and RTS signals? If I follow a process like:
- Press boot
- Press en
- Release en
- Release boot
- Run 'make flash' from the terminal with the FTDI TTL-232R device
At this point I see the connecting output with ...____...___...___ etc and it fails.
If I repeat button process above while connected via 'make monitor' or 'make simple_monitor' I see from the esp32 something like "Waiting for download" which appears to indicate the device is in the correct mode, but it won't program when in this mode via 'make flash'.
Is esptool looking for the state of one of those hardware flow control lines before starting?