Custom board, no serial data received error, but is able to go into download mode

[anees.ahmad.jaffer]

I have made a custom board using the esp32-wroom-32d. Board powers on. Connecting to USB of my laptop, opening putty at 115200, the board starts with this message:

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ets Jun  8 2016 00:22:57

rst:0x1 (POWERON_RESET),boot:0x2 (DOWNLOAD_BOOT(UART0/UART1/SDIO_REI_FEO_V2))
waiting for download

When I press the button connected to the third pin on the MCU, RST, the board constantly resets, with the message:

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ets Jun  8 2016 00:22:57

rst:0x1 (POWERON_RESET),boot:0x12 (SPI_FAST_FLASH_BOOT)
configsip: 0, SPIWP:0xee
clk_drv:0x00,q_drv:0x00,d_drv:0x00,cs0_drv:0x00,hd_drv:0x00,wp_drv:0x00
mode:DIO, clock div:2
load:0x3fffeba4,len:4
load:0x4009f000,len:3248
entry 0x4009f574
▒OHAI▒

After that, if I press the button connected to IO0, pin 25, I get this message once:

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rst:0x10 (RTCWDT_RTC_RESET),boot:0x2 (DOWNLOAD_BOOT(UART0/UART1/SDIO_REI_FEO_V2))
waiting for download

When I try to upload code through PlatformIO, Arduino IDE, or WSL, it fails. The error in WSL is:

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esptool.py v3.3.2
Serial port /dev/ttyS19
Connecting......................................

A fatal error occurred: Failed to connect to ESP32: No serial data received.
For troubleshooting steps visit: https://docs.espressif.com/projects/esptool/en/latest/troubleshooting.html

[ESP_Sprite]

Are you sure you don't have a terminal open while uploading? You can't have two programs on the same serial device, and the OHAI message does suggest that's what you have. (OHAI is a handshake for the flashing stub)

[bidrohini]

I think you must troubleshoot your PCB also. See if there is any broken trace or short circuit.

[anees.ahmad.jaffer]

Are you sure you don't have a terminal open while uploading? You can't have two programs on the same serial device, and the OHAI message does suggest that's what you have. (OHAI is a handshake for the flashing stub)

Hi. Yes, 100% sure. If I purposefully leave a terminal open, then try to flash it, the error specifically says access denied. I also closed all programs, restarted the laptop, just to make sure there's no open serial ports. Still get the error.

[anees.ahmad.jaffer]

I think you must troubleshoot your PCB also. See if there is any broken trace or short circuit.

Hi. I've gone with a multimeter, checked that 5v, 3.3v and ground are not shorted. Check continuity from the USB programmer to the ESP chip's RX and TX pins. All that should be connected is connected, all that shouldn't be connected is not connected (from what I've tested). I've also tried cutting the traces for the GPIO's that I would've used for what this device would be used for. Still same error. I've tried soldering wires directly to the RX TX pins of the ESP, then connecting that to an FTDI programmer. No luck, but that may have been my soldering skills.

[anees.ahmad.jaffer]

Here are the schematics for my PCB:

Power schematic:

Power schematic

2.png (74.33 KiB) Viewed 4215 times

USB programmer schematic:

USB programmer schematic

3.png (102.32 KiB) Viewed 4215 times

Here is the PCB design:

PCB design

5.png (266.94 KiB) Viewed 4215 times

Note: the green lines are islands that were not filled correctly. I have taken a dremmel and cut these islands. Tested with a multimeter, the islands are no longer connected to the tracks, and the tracks are connected where they should be