CrossPoint for the Xteink X4 Pro Unofficial · early beta
Install the CrossPoint e-reader firmware on your X4 Pro from the browser. It takes about two minutes. Two units can also be paired as a two-page book over their built-in radio.
1 Put the X4 Pro in download mode
- Unplug the USB cable and, if the unit is on, switch it off.
- Press and hold the left page button.
- While holding it, plug in the USB-C data cable, keep holding for about 3 seconds, then let go.
The screen stays as it was in download mode. A charge-only cable won't work. If the screen shows the reader after you plug in, it is not in download mode: start again.
2 Connect
Click the button, pick USB JTAG/serial debug unit in the list, and wait for the checks.
3 Install
Only the first app slot (0x10000) is written. Your bootloader, partition table, settings and books are not touched.
Want a copy of the Xteink firmware first?
Reading 8 MB over the browser's serial port stalls too often, so this page doesn't offer it. With
esptool (pip install esptool) and the unit in download mode:
esptool --port PORT read-flash 0x10000 0x7e0000 x4pro-app-backup.bin
PORT is /dev/cu.usbmodem… on macOS, /dev/ttyACM0 on Linux, COM3 or similar on Windows. Keep the file private, as it is Xteink's software.
To put it back, use Install my own firmware file below.
Other options
A file of your own must be an app image for the ESP32-S3, not a full-flash image. This is also how you put back a copy saved above.
Working…
Keep the cable plugged in and this tab open until it says it's done.
Pairing two units as a two-page book
- Install CrossPoint on both units with this page, then put the book on the left unit's SD card. The right unit gets its own copy over the radio when you open it; a copy already on its card must have the same file name and size.
- On each unit open Settings and choose Link to second unit. Choose Left page on one and Right page on the other. They find each other by radio on their own.
- Open the book on the left unit. The right unit opens it too and shows the next page. If the right unit's card doesn't have the book, the left unit sends it over the radio (about 25 KB/s, so a 1 MB book takes under a minute) and the right unit shows its progress. Closing the two units together locks touch and turns the light off; opening them undoes it.
To unpair, use Cancel link in the link screen on either unit.
Technical log
Having trouble?
- The unit isn't in the list. It must be in download mode (step 1) and plugged in with a data cable. Try another USB port, and avoid hubs.
- "Busy" or "could not open". Close other tabs or apps that use the unit's serial port (serial monitors, other flashers), then unplug and redo step 1.
- It says the partition table is not the stock one. This flasher only supports X4 Pro units with the original layout and refuses to write anything otherwise. Nothing was changed.
- It says the unit starts from the second app slot. An update has moved the unit there. Nothing was changed; a new image in the first slot would not run.
- After flashing nothing happens. Unplug the cable, wait 15 seconds, plug it in again and press the power button briefly. If it still does nothing, redo step 1 and flash again.
- Linux: if the browser can't open the port, add yourself to the
dialout(Debian/Ubuntu) oruucp(Arch/Fedora) group, then log out and in.