MonoFrame

MonoFrame is an open-source (MIT) e-ink picture frame. You flash the firmware onto your own frame using a standard ESP32 flashing tool of your choice — this page shows you how. You only do this once; after that, the MonoFrame iOS app handles all setup and updates over WiFi.

Flashing rewrites the frame's firmware and erases its settings. As with any firmware flashing, you do this at your own risk — the software is provided as-is, without warranty, per the MIT license.

Supported frames

Elecrow CrowPanel ESP32-S3 4.2″ e-paper display (400 × 300)
Elecrow CrowPanel ESP32-S3 5.79″ e-paper display (792 × 272)
Seeed reTerminal E1001 7.5″ monochrome ePaper terminal (800 × 480)

Have a different e-ink frame you'd like supported? Request it here — or add a 👍 to an existing request.

Step 1 — Download the firmware

Grab the binary for your panel size from GitHub Releases:

⬇ CrowPanel 4.2″ ⬇ CrowPanel 5.79″ ⬇ reTerminal E1001

All releases and checksums: github.com/jbaker00/MonoFrame/releases. The binaries are complete images (bootloader + partition table + app), so one file is all you need.

Step 2 — Flash it

Plug the frame into your computer with a USB-C data cable (a charge-only cable won't work), then use whichever tool you prefer. The parameters are the same everywhere:

Chip	`ESP32-S3`
Flash offset	`0x0`
Baud rate	`115200` (higher is often unreliable on these boards)

Option A — In your browser (easiest)

Open Adafruit's WebSerial ESPTool in Chrome or Edge (Safari and phones won't work).
Set the baud rate to 115200 and click Connect, then pick the USB serial port that appears.
In the first file row, click Choose a file… and select the monoframe-fw-*.bin you downloaded. Set its offset to 0x0.
Click Program and wait for it to finish (a couple of minutes).

Option B — Command line (esptool)

Install esptool: pip install esptool (or brew install esptool on macOS).
Find your serial port: on macOS/Linux run ls /dev/cu.usb* /dev/ttyUSB* /dev/ttyACM*; on Windows check Device Manager for the COM port.

Flash:

esptool --chip esp32s3 -p YOUR_PORT -b 115200 write-flash 0x0 monoframe-fw-42.bin

(swap in the .bin for your frame)

Option C — Windows GUI (Espressif Flash Download Tool)

Download the Flash Download Tool from Espressif.
Choose ChipType ESP32-S3, WorkMode Develop.
Add one row: your monoframe-fw-*.bin at address 0x0, and tick its checkbox.
Set SPI SPEED 40MHz, SPI MODE DIO, select your COM port, baud 115200.
Click START and wait for FINISH.

Step 3 — Set it up

Unplug the frame from the computer and power it on (the reTerminal E1001 has a power switch on the back). Within a minute the screen shows Setup Mode with a hotspot name and a WiFi code.
Open the MonoFrame app on your iPhone and tap My Frames → Add a Frame — the app walks you through the rest.

Troubleshooting

No serial port appears: your cable is probably charge-only — try another USB-C cable.
Tool can't connect to the chip: hold the frame's BOOT button while plugging it in to force download mode, then try again.
Flashing fails partway: just run it again — a failed flash is recovered by flashing again, and can't harm your computer.

Source code, issues, and firmware releases: github.com/jbaker00/MonoFrame.