Esp32 on Notebook

Neovim and Rustaceanvim With Esp Toolchain

Sat, 29 Aug 2026 14:28:29 +0100

I was trying to get cargo to use the custom esp toolchain from Espressif, but use stable for rust-analyzer because the esp toolchain does not include a rust-analyzer component.

Neovim has a built-in option to load user-defined config at the project level called excr, which can be enabled with:

vim.o.exrc = true -- enable project local config

With this enabled, the following .nvim.lua will merge the global configuration I have set for vim.g.rustaceanvim (and this is helpful because I have settings for use with the bacon-lsp as well):

ESP32-C5 Programmable Usb

Sun, 23 Aug 2026 13:04:17 +0100

TL;DR: it can’t be done.

The USB peripheral on ESP32-C5 is non-programmable and only supports serial/JTAG (unless they release a new MCU).

ESP32, Embassy & Sockets

Sun, 09 Aug 2026 12:02:50 +0100

The Problem

I was running a webserver (picoserve), but I was only able to run one worker; somewhere in the picoserve code I was running into a panic from SocketSet add function, specifically this panic:

match &mut self.sockets {
 ManagedSlice::Borrowed(_) => panic!("adding a socket to a full SocketSet"),
 #[cfg(feature = "alloc")]
 ManagedSlice::Owned(sockets) => {
 sockets.push(SocketStorage { inner: None });
 let index = sockets.len() - 1;
 put(index, &mut sockets[index], socket)
 }
}

The problem, I eventually figured out, was that the network stack created with embassy-net was being initialized with 3 sockets: one for DHCP, one for DNS, and one for the rest of the code.

Lily T-Dongle S3 SD Card Pins

Sun, 19 Jul 2026 10:28:54 +0100

SD Card pin numbers for use with SPI

LilyGo Pin Name	GPIO #	SPI
SDMMC_D0	14	MISO
SDMMC_D1	17
SDMMC_D2	21
SDMMC_D3	18	CS
SDMMC_CLK	12	SCK
SDMMC_CMD	16	MOSI

Example

let spi_bus = Spi::new(
 peripherals.SPI2,
 spi::master::Config::default()
 .with_frequency(Rate::from_khz(400))
 .with_mode(spi::Mode::_0),
)
.unwrap()
.with_sck(peripherals.GPIO12) // clk
.with_mosi(peripherals.GPIO16) // cmd
.with_miso(peripherals.GPIO14) // d0
.into_async();

let sd_cs = Output::new(
 peripherals.GPIO18, // d3
 Level::High,
 OutputConfig::default().with_pull(Pull::Up),
);
let spi_dev = ExclusiveDevice::new(spi_bus, sd_cs, Delay).unwrap();
let sdcard = SdCard::new(spi_dev, Delay);

Flashing ESP32 Mini SD Card

Sun, 21 Jun 2026 18:40:16 +0100

For most ESP32 projects, a microSD card should be formatted to FAT32.

FAT32 only supports microSD cards up to 32GB.

# find the sd card with lsblk, then unmount it
sudo umount /dev/mmcblk0

# format in fat32 command
sudo mkfs.vfat -F32 /dev/mmcblk0

Connecting to ESP32

Tue, 09 Jun 2026 08:45:33 +0100

Note

The hardware in this example is the ESP32-C3-DevKit-RUST-1 on Arch