Lights, verdicts and messages
What the board's LEDs, its one-line health verdict, and the notes on its pages can tell you — and what to do about each.
1. The LEDs
The board's LEDs are the diagnostics that work with no network and no computer. What they show depends on the LED mode (led_mode, the LEDs selector on the Live page):
| Mode | What the LEDs show |
|---|---|
| Magnitude meter (the default) | The status LEDs form a bar graph of signal strength. From firmware v482 the bar jumps up for each lightning event chosen by Lightning indicators (below), to that event's magnitude step; before v482 it jumped with each captured signal, by its strength relative to the trigger threshold. The bar falls back over about a second, and a single dot holds the peak for about two seconds. Between events the bar's base LED breathes gently — that is the sign the capture path is running; a frozen or dark base LED means it has stopped. The individual LED meanings below do not apply in this mode, except that the Fault LED lights steadily whenever there is a fault. |
| Classic | Each LED has its own meaning, as in the table below. |
| Blind | Every controllable LED is off, the Fault LED included. Only the hard-wired power LED stays lit. |
From firmware v482, the Lightning indicators setting on the Live page selects which lightning events light the meter and the classic mode's Signal LED: by default, lightning whose location used this station’s timestamp; alternatively, any lightning the network locates within 250 km, even without this station’s participation. Both come from the Denko lightning service after the network has located the stroke, so the LEDs light after the service reports the stroke. The station accepts a used-event confirmation for up to 90 seconds after it sent its signal, and a nearby report only while the stroke is no more than 90 seconds old. A late or unlocated stroke lights nothing. Both need the station to be registered with the lightning network. Captures alone no longer light the meter or the Signal LED. Used events show the magnitude step of the signal this station reported; nearby events show the magnitude supplied by the Denko service and need a current satellite position. When switched on, the buzzer follows the same events, beeping once per magnitude step, up to seven times. It is off by default. The LEDs appearance selector remains separate.
In the classic mode:
| LED | Meaning |
|---|---|
| Mode | The heartbeat: blinking means the application is running and the capture path is alive. Dark on a powered board (and in every mode, every LED dark) means one of two things: the board is in its recovery image (the network up, a plain-text page at the station's address saying it is installing its firmware — leave the power on; it restarts by itself when the installation is done, section 9), or nothing starts at all (no network answer either — recover over USB DFU, firmware chapter, section 3). |
| Network | On while the Ethernet link is up. |
| GPS | On while the clock is locked to the satellites' 1PPS signal. Off for the first minutes after power-on is normal; if it stays off, check the GPS page and the antenna’s view of the sky (chapter 3). |
| Signal | From firmware v482, flashes briefly (about 0.15 s) for each lightning event chosen by Lightning indicators (above); earlier firmware flashes once per captured signal. Dark between events is the normal state most of the time. |
| Fault | Lit when the measurement converter is not running or the satellite receiver could not be started. Read the verdict line and the counters on the Diagnostics page for what it is; restart the board once, and contact Denko if it returns. |
2. The verdict line
On the Diagnostics page, next to the boot journal, the station answers “am I healthy right now?” in one line, judged once a second. Three bad seconds in a row are needed to call it unhealthy, and two good ones to call it healthy again, so a single odd reading never flips it.
From firmware v440 the line says this in words. Earlier firmware shows a short code instead; the code is also what /api/status reports on every version. Both forms are listed:
| Shown (from v440) | Shown (earlier) | Meaning |
|---|---|---|
| healthy | OK | Healthy by the latest evaluation. |
| starting up | INIT | Not yet judged since boot. Normal for the first seconds. Reasons after it (starting up · …, or INIT: + reasons) mean something is already wrong but has not lasted long enough to call. |
| healthy · now: + reasons | OK? + reasons | Something is wrong, but not persistently — a dirty reading that may clear by itself. |
| not healthy · + reasons | BAD: + reasons | Persistently unhealthy. The reasons name what, worst first. |
The verdict is advisory: it describes the station’s condition. Read its reasons and the related page readings before deciding what to do.
| Reason (code · words from v440) | Meaning | What to do |
|---|---|---|
faulta crash was recorded on the previous boot | This boot follows a recorded processor fault. | Note the firmware version and contact Denko if it repeats. |
crashthe previous run ended unplanned (watchdog or crash) | The previous run ended unplanned — watchdog or fault. | As for fault: once is an event, a pattern is a bug worth reporting. |
adccapture is not running or is restarting | The measurement converter is dead or being restarted: no captures are happening. From v440, once capture is running again the reason reads capture was restarted this boot instead: the converter stalled and was restarted, and it stays listed until the next restart of the board. | Check the Diagnostics ADC row. Restart the board; if it stays, contact Denko. |
ringcaptured data was dropped (the reader fell behind) | Captured data was dropped — captures cannot be trusted while this counts. | Restart the board; if it recurs, contact Denko. |
nofixno GNSS fix | No satellite fix, past the 10-minute grace after boot. | Give the GPS antenna more sky (chapter 3). |
nokeyno valid lightning-network key | The selected compatibility profile (10.1 or 11.x) needs a valid registration to send, and the station does not currently hold one — registration has not completed, or it has lapsed. | Check the registration note (section 4) and network reachability; contact Denko if it stays. |
3. The boot journal
The Boot journal beside the verdict is the durable half of the pair: which firmware images ran, for how long, and why each stopped, newest first, in the form boots=[version:seconds:reason …]. A board that restarts every minute tells that story there even when you cannot catch it in the act. The reasons:
| Reason | Meaning |
|---|---|
ota · stock | A planned restart to install a firmware update, or to stage the stock firmware. |
trial | A new image on trial could not confirm itself in time and restarted (chapter 5). |
user | A restart someone asked for. |
wdt · wwdt · fault | Unplanned: a watchdog fired, or the processor faulted. One is an event; a pattern is worth reporting. |
escape | After repeated crashes the board handed over to its recovery image. |
power · pin · lpwr · soft · unknown | Power was cut or switched on, the reset button was pressed, a low-power reset occurred, a software reset without a recorded reason, or no reason could be determined. |
A processor fault also appears after the journal as fault: with its details — quote it when you report the problem.
4. Registration notes
The Lightning network row on the Diagnostics page reports registration when it is enabled. It shows station N once registered, otherwise not registered, followed by a note that says where the process stands:
| Note | Meaning |
|---|---|
| registered | Registered; N is the station number the network assigned (chapter 6). |
| waiting for a fix; will not declare 0N 0E | No satellite position yet, so registration is deliberately waiting. Normal until the first fix. |
| 2D fix; will not declare a sea-level altitude | A position without height. Registration still waits — one more satellite, usually. |
| no nameserver from DHCP yet · resolving the control host · resolving the next hop · posting | Registration is in progress: finding the server and sending the request. Seconds, normally. If it stays on no nameserver from DHCP yet, the network did not give the board a DNS server. |
| no reply -- timeout, reset, or refused | The registration server did not answer. Retried automatically; check the network if it persists. |
| server refused the request (HTTP code) | The server answered but rejected the request — for example a processor ID not linked to any account. Link the board; the station retries every 5 minutes. |
| server answered but assigned no id | The server replied without a station number. Usually the board is not linked to an account yet. |
| protocol changed; old reply discarded | The compatibility profile changed while a request was in flight; the station asks again. |
| body would not build | The station could not assemble its request. Contact Denko if it stays. |
5. Network states
| Shown | Meaning |
|---|---|
| DHCP: discovering / requesting | Still asking for an address. Seconds, normally. |
| DHCP: bound | Has an address. Normal. |
| DHCP: no answer — using the compiled address | No DHCP server answered, so the board took its fallback address in the 192.168.6.x subnet, and keeps asking for DHCP in the background. Reachable only if your network matches — give it DHCP (Quick start). |
| Address: none yet · gw: none | No address, or no gateway to send off-subnet traffic through. The collectors are all off-subnet: nothing leaves the board. |
| Lightning network / Denko: off · on · on · no collector yet · always on | Per-network participation (chapter 8). no collector yet means enabled, but with no usable destination learned so far. From firmware v482 the Denko row adds always on: Denko cannot be switched off. shared with the lightning network on the Denko row means both networks use the same destination, so the station sends once and counts it under the lightning network. |
| Network choice: the station did not accept that | A participation change was refused. The state that matters is the one the page reads back. |
| Network choice: not stored · attempt(s) did not reach flash | The choice was made but could not be saved; it will not survive a restart. Try again; if it repeats, contact Denko. |
| Aborted uploads · peer stopped sending; running image untouched | An upload to the station was cut off part-way. Nothing was changed. |
6. Detector, GPS and capture warnings
| Shown | Meaning |
|---|---|
| ADC: NOT converting | The sample ring never filled — started or not, there are no captures. See adc in section 2. |
| Interference: noise / burst | The trigger rate is high enough that the station calls the input interference, not weather. Move the antenna away from electrical equipment; check the spectrum on the Live page. |
| Triggers (N over the rate limit) | The per-second rate cap fired; N triggers were deliberately not captured. A dead input does this continuously — the cap is what keeps the board serviceable. (Before v440: N over rate_max.) |
| Ring laps · batches dropped: new samples overwrote ones not yet read | Batches were dropped: acquisition overtook the reader. Should be zero; see ring above. (The note quoted is the v440 wording; earlier firmware words it differently.) |
| Late windows | A trigger was found after part of its window had already passed. Occasional counts are harmless; a fast-growing count is worth reporting. |
| Reader trims · old frames skipped | The reader fell behind and skipped old frames to catch up. Expected now and then while the station's pages are being served. |
| Timestamp drops | A capture was dropped because one coherent trigger time could not be established. Should be zero. |
| Unusable windows | A capture was dropped because its sample window did not survive until readout. Should be zero. |
| ADC restarts · capture path recovered | The capture path stopped and was restarted by the watchdog. It recovered by itself; a growing count is worth reporting, together with the details shown after at restart:. |
| Tone rejects · dropped, dominated by a steady tone (tone rejection) · Tone track | Windows dropped because a steady tone dominated them (the tone reject, reject_hz and the automatic tracker), and the tracker's state: off, learning, active, or manual, with the frequencies it answers to. (Before v440 the note read dropped, tone-dominated (reject_hz).) |
| Antenna: SHORT · OPEN | SHORT is a fault in the GPS antenna cable or connector. OPEN is normal with the standard passive antenna; if you use an external antenna with an amplifier (active antenna), then it is not getting power: check its cable and connector (chapter 3). |
| open-detect off, so "ok" only means not shorted | Open-circuit detection is switched off (ant_ocd 0, the default), so the receiver can only report a short. |
| open-detect REFUSED | Open-circuit detection was asked for, and this receiver will not take it. |
| UART saturation · label(s) withheld | The receiver's messages arrived faster than the station could account for them, so the station held its clock unlocked rather than risk a wrong timestamp. Shown only once it has happened; a count that keeps climbing is worth reporting. |
| Held in flash: no — a reboot would use the compiled defaults | No remote configuration has been stored on the board yet. |
| Truncated fetches · file too large — nothing applied | The remote configuration file was too large to read, so none of it was applied. The station keeps its previous settings. |
7. Firmware update outcomes
The Firmware update section of the Diagnostics page says what the last update checks found, each with how many times in a row (×N):
| Outcome | Meaning |
|---|---|
| not enabled (fw_seq is 0) | Self-updating is switched off for this board by the remote configuration (fw_seq 0). Updates are on by default, so this is a deliberate choice for this board (chapter 5). |
| offered version is not newer | The offered release is the same version as, or older than, the version running. Normal. Releases reach stations in stages; this message does not mean every station has been offered the same version. |
| update started | A newer release was found and handed to the recovery image to install. |
| manifest unreachable: no DNS answer or no route · connection failed or timed out · HTTP N · not a usable manifest · reply too large | The update server could not be reached or gave an unusable answer. Retried by itself; check the board's internet access if it persists. |
| signature not OK | The update was not signed as expected and was not installed. |
| refused: this image is still on trial | Normal right after an update: the new version has not confirmed itself yet (chapter 5). Clears by itself. |
| refused: checking the ring's release against golden's manifest | Normal and brief while a new release is being delivered: before installing, the station checks that its recovery image will install the same release it was offered. It checks again straight away. |
| refused: golden's manifest names another release, vN | The recovery image would install a different release (vN) from the one this station was offered, so the station waits and checks again later. Normal while a new release is being delivered; it clears by itself. |
| refused: handoff back-off (N s left) | Earlier handovers to the recovery image did not end in a confirmed update, so the station waits the time shown before trying again. The wait grows with each attempt, up to a day. Clears by itself. |
| refused: installed golden is not bootable | The recovery image that installs updates is damaged, so the station stays on its current version. It repairs the recovery image by itself in the background; keep it powered on (recovery refresh guidance). If it stays, contact Denko. |
| refused: stock staging owns the flash | A conversion to the stock firmware was started on the Firmware page and has not finished (section 8). The update waits until the conversion is completed or abandoned; do not restart merely to abandon a staged conversion. Stay on the Firmware page and complete or retry the upload and step 2 (chapter 5). |
| refused: waiting for the console enrollment restore to finish · Golden updater owns flash | Firmware v484 and later: the station is still restoring its remote-console registration, or refreshing its recovery image. Keep it powered on; the update follows by itself (recovery refresh guidance). If the first one is still the outcome after the next check about 30 minutes later, restart the station. |
| refused: not running from the application slot · boot log does not name a confirmed application | Rare: the station cannot confirm that it is running its normal, confirmed firmware, so it does not hand over an update. If it stays after a restart, contact Denko. |
8. Firmware page messages
| Message | Meaning |
|---|---|
| that file size is not an official stock BLUE 9.4, 10.0, 10.1 or 11.0b3 image | Only the four exact published files are accepted (chapter 5). Get the right file. |
| entering golden recovery · verifying golden recovery · prepare response lost; checking golden recovery | Step 1 is switching the station into recovery before uploading. Keep the page open and power on while it checks that recovery is ready. A lost prepare response does not establish failure; the page checks the station. |
| Could not read the selected file. | The browser could not read the file you chose. Choose it again. |
| staging - this erases the staging sectors first, so the first seconds look stalled | Normal. Do not power off. |
| verified official image is staged; ready for step 2 | The stock image is verified and waiting; step 2 writes it and reboots. |
| upload failed: … | The upload did not complete. Press step 1 again. |
| writing - do not power it off · this page will stop responding | The conversion is committed and the board is becoming a stock station. Expected. |
| refused: … · Connection lost; check the station state before retrying | The commit was refused or its outcome is unknown. Check current station state before any retry; contact Denko if the station stays unavailable. (Firmware before v482 words the second message Connection lost; verify the board before retrying.) A refusal saying … owns flash can mean a temporary recovery refresh, and a console enrollment copy is still being restored (firmware v482) means the station is still restoring its remote-console registration; in both cases keep power on, wait and retry. See recovery refresh guidance. |
| Refreshing the recovery image. Wait for the refresh to finish; keep the station powered on. Downloaded … of … bytes. | Firmware v482 and later: the station is refreshing its recovery image in the background, and the conversion controls stay hidden until it has finished. The page checks again by itself every 2 seconds and shows the download progress when it is known. Keep the power on and wait. |
| Browser stock restoration is currently unavailable… | Restoration is unavailable right now, including while a recovery refresh owns flash. From firmware v482 the message goes on Wait for the station to finish its current task., and the page checks again by itself every 2 seconds. This message alone does not prove an unsupported layout or a need for USB DFU/SWD. Wait, reload and check state; contact Denko if it persists. |
| Could not verify recovery status… | The station has not answered the page’s status request. Keep the station powered on and wait; from firmware v482 the page asks again by itself every 2 seconds, otherwise reload it. This message alone does not prove a flash-layout fault or require USB DFU/SWD; contact Denko if the station stays unavailable. |
| Could not verify flash layout… | Firmware v475 wording of the message above. The page could not read station status, so controls remain hidden. A failed status read is not proof of a flash-layout fault or a need for USB DFU/SWD. Wait and reload; contact Denko if the station stays unavailable. |
9. Recovery page messages
While the board's recovery image runs, the station's address shows a single line of plain text instead of the web interface, and every indicator LED is dark. The one exception is step 2 of the Firmware page conversion: there the station's main page and its Firmware page are the upload page, and the line is what the station's other page addresses show.
| Message | Meaning |
|---|---|
| DENKO Blue is installing its firmware. Do not power it off. This takes up to about 5 minutes; the station restarts by itself when done. | The first install from the installation page, or an update, is being written. Leave the power on and wait; the normal web interface comes back by itself, usually within about 5 minutes. A slow connection can make it take longer. If the page is still there much later, check the station's internet connection: it keeps retrying on its own, and it does not need USB recovery (chapter 5). |
| DENKO Blue is ready to receive the firmware file. Open this station's main page and upload the file there. If no file arrives within 30 minutes, the station restarts by itself. | Step 1 of the Firmware page conversion has finished (section 8); continue with step 2 on the station's main page. After 30 minutes without upload progress, the station restarts by itself. If it then shows the installing page, keep power and internet connected and wait; a partial upload may have affected the normal firmware. |
| DENKO Blue recovery mode: checking for application firmware | A board with an older recovery image shows this line in place of the installing message above. It means the same: leave the power on and wait; the station restarts by itself. |
| DENKO Blue recovery mode: waiting for official stock image | A board with an older recovery image shows this line in place of the ready message above. It means the same: continue with step 2 on the station's main page. |
Wi-Fi setup network and setup password: not applicable. DENKO Blue uses wired Ethernet and has no Wi-Fi setup network or setup QR code.
10. Page not found
| Message | Meaning |
|---|---|
| Page not found · This page does not exist on DENKO Blue. | Firmware v482 and later: the address typed after the station’s IP address does not exist on the station. Use Go to the front page, or check the address. The page follows the language selector like the station's other pages. The addresses the stock firmware's update screen leaves in the browser are not affected: they lead to the front page by themselves (chapter 5). Firmware before v482 answers an unknown address with the plain text no such path. |