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Prerequisites

Gather these before you open the flasher.

Hardware

Item Notes
Heltec WiFi LoRa 32 V4 This walkthrough targets Heltec v4 in the MeshCore flasher
USB-C data cable Charge-only cables do not expose serial
LoRa antenna Fit it before you transmit

Computer

Host checks below are from Fedora. On another OS, use the matching browser and serial permissions.

Item Notes
Chrome, Chromium, or Edge Web Serial required — Firefox alone is not enough
Serial access on Linux User in dialout (or equivalent); re-login after adding
usbutils Provides lsusb

Confirm the package (Fedora):

rpm -q usbutils

usbutils-017-3.fc41.x86_64

If missing:

sudo dnf install usbutils

Complete!

Confirm serial group membership:

groups

you wheel dialout

dialout must appear. If it does not, add your user and re-login:

sudo usermod -aG dialout "$USER"

# no output on success — log out and back in, then re-check groups

USB identity after you plug the board in:

lsusb | grep -i espressif

Bus 003 Device 076: ID 303a:1001 Espressif USB JTAG/serial debug unit

Serial node (path and bus/device numbers can differ):

ls -l /dev/ttyACM* /dev/serial/by-id/ 2>/dev/null

crw-rw---- 1 root dialout 166, 0 Oct  1 20:37 /dev/ttyACM0

/dev/serial/by-id/:
total 0
lrwxrwxrwx 1 root root 13 Oct  1 19:53 usb-Espressif_USB_JTAG_serial_debug_unit_10:BD:A3:5B:13:E0-if00 -> ../../ttyACM0

That proves USB — next, identify and select Heltec v4.

Tools

Next: Identify the board.