DT5490 firmware — user guide

This firmware runs on the control board of the DT5490 high voltage power supply. It drives the high voltage module, the front panel and the Ethernet port, and it is updated from the web interface.

What the firmware does

Front panel

• Live output voltage, output current and temperature on the display.
• High voltage on/off and target voltage from the encoder: turn to change the value, press to confirm. The value blinks while it is being edited.
• A long press opens the settings: temperature sensor, isolated output, HV state at power-on (off, last state, on), Ethernet (DHCP, reset), MAC, product id, IP address, host name and firmware version.

Web interface

Open the instrument IP address in a browser.

IV sweeps and voltage profiles are run by the browser: keep the page open until they finish. The setpoints they send are not saved in the instrument memory; the final state is.

The files of a release

Each release of the dt5490-up package contains two files for the user.

Why two files:

• The .dtfw file is the firmware packed with a header (version, size, MD5 checksum). The instrument receives it, checks it, and only then writes it into its own memory. The bootloader and your settings (network, high voltage) are never touched. This is the file to use every time.
• The .hex file is the plain application image. It is written by the recovery tool through the bootloader, which is a small program that stays in the instrument and is never erased by an update. It exists for the rare case in which the application is missing or damaged, for example after a power loss in the middle of an update.

Updating the firmware

1. Switch the high voltage output off.
2. Open the web interface and go to System, then Update firmware.
3. Choose the .dtfw file. The page shows the version and checks the file.
4. Press Upload. When the instrument has checked the file it shows "ready to be written in flash".
5. Press Write to flash, read the warning, then Write and restart.
6. Do not switch the instrument off while the countdown is running (up to 5 minutes). The instrument writes the new firmware and restarts; the page reconnects by itself and returns to Home.

The new version is shown in System and in the front panel settings.

Recovery: when the instrument does not start

If an update was interrupted the display can show a red screen:

No app in flash
Use recovery tool
to upload firmware
IP: 192.168.50.2

The instrument is then waiting for the recovery tool. You need the recovery tool (UDP bootloader) and the dt5490-up-recovery-application-<version>.hex file.

1. Connect the PC directly to the Ethernet port of the instrument.
2. Give the PC a fixed address in the same network, for example 192.168.50.10, mask 255.255.255.0. The bootloader always uses 192.168.50.2, whatever address the instrument normally has.
3. Start the recovery tool, set the address 192.168.50.2 and connect. The display shows "Bootloader mode".
4. Load the recovery .hex file, program it and verify it.
5. Start the application from the tool, or switch the instrument off and on.

Your network and high voltage settings are kept: they are stored in a separate memory.

Entering the bootloader when the application works

At every power-on the display shows the white start screen with "Booting..." and the address 192.168.50.2 for about 6 seconds, then the application starts. If the recovery tool connects during those seconds the application is not started and the instrument stays in bootloader mode. This is useful to reinstall a firmware from scratch.

After a recovery, the next updates can be done again from the web interface with the .dtfw file.