ESP32 Pico -D4 will not connect to arduino IDE

Hi all. I have a ESP32 pico D4 chip that i want to program. The circuit is very bare it includes just the chip a pull up resistor for the enable pin and a programming port. The port I designed is connecting 6 pins to a serial bridge.

EN pin9-EN
IO/0 pin 23 - IO/0
U0TX pin 41 - RX
U0RX pin 40 -TX
3.3v - 3.3V

The chip powers up and sucks 5mA of current so I know it is on and functioning properly. However the connection sequence goes on forever.

I’m using the latest Arduino version 1.8.12 and these programming parameters.

Board: esp32 pico kit
upload speed: 921600
partition scheme: default
Core debug LV: None

parallel programmer.

I’m running the latest version of Windows 7.

I have dozens of ESP32 wroom boards that program just fine. I can’t get one of theses pico chips to program at all.

What am I missing?

The chip powers up and sucks 5mA of current so I know it is on and functioning properly

in this document it states that 80mA is the standard consumption and you should deliver 500mAdocument

OK that does seem suspicious now that you mention it. Here are the pins I have connected to 3.3V. Let me know If I missed any.

3.3V Connected:


The only pin I have connected to ground is EP_GND which is the large power pad underneath the chip.

Where did I mess up?

Where did I mess up?

maybe by signalling the boot mode using GPIO 0 & GPIO,

IO/0 pin 23 - IO/0

ah that is what you mean ! Other option would be that the chip is waiting for upload and therefore uses little power, i am reluctant but i have to ask if you have RX & TX the right way round ? For the rest i think i would have done it the same way. Check the solder work, that i would do.. it wouldn't be the first time, make sure the connections are actually conductive.