Telemetry

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Telemetry

Everything on the tester screen except the pack voltage comes from the ESC. This page is about where each number came from and how much to trust it.

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Two and a half sources

eRPM rides on the DShot signal wire itself and works on every ESC that supports bidirectional DShot. If the link works at all, you get RPM.

EDT — Extended DShot Telemetry — carries voltage, current, temperature, stress and a status byte on that same wire, interleaved between eRPM frames. It needs support in the ESC firmware and it needs to be switched on. The firmware does that for you; see below.

KISS telemetry is an optional third wire from the ESC's telemetry pad. It is finer (0.01 V and 0.01 A against EDT's 0.25 V and 1 A steps) and it carries consumed mAh, which EDT has no room for at all. See the third wire.

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The tiles

Tile	Source	Notes
VOLTAGE	KISS if fresh, else EDT	The tag on the label row says which
CURRENT	KISS if fresh, else EDT	Same
ESC TEMP	KISS if fresh, else EDT	Turns red at 90 °C and above
STRESS	EDT only	0–255, the ESC's own load figure. Amber above 200
ESC STATUS	EDT only	OK / WARN / ERROR / ALERT. Exact meaning is ESC-firmware specific
LINK	Neither — this is our own count	Good packets per second, and the checksum error rate over the last second

Consumed mAh appears in the corner of the temperature tile, and only with KISS.

The small KISS / EDT tag

The voltage and current tiles carry a tag on their label row: cyan KISS, dim EDT. It is not decoration. 12.25 V from EDT means "somewhere in a 0.25 V bucket"; the same reading from KISS means "within 0.01 V". If a tag drops from KISS back to EDT, the telemetry wire has gone quiet and the readout just got twenty-five times coarser without the number visibly changing.

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Why a tile reads --

Every reading expires. A value that has not been refreshed within its window blanks to -- rather than holding its last number, and the RPM digits go dark red.

This matters more than it sounds. Unplug the ESC, or swap it for a different one, and a display that keeps the old figures is not showing stale data — it is showing a plausible, confident reading from hardware that is not attached. -- is the honest answer.

So -- means one of:

• the ESC does not support EDT at all (you will still get RPM);
• EDT is supported but is not switched on yet — watch the chip on the settings screen and give it a moment;
• the ESC stopped answering.

An expired status tile never reads OK. It reads --. A warning indicator is not allowed to fail in the direction of "all clear".

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Switching EDT on

You do not. The firmware does, and keeps doing it.

The rule is "is it working", not "have we asked": while an ESC is answering eRPM and no EDT frame has arrived for a second, the enable goes out again every second. Lose the link and the state resets, so an ESC connected later, power-cycled, or swapped for a different one gets its own enable rather than silently running without telemetry for the rest of the session.

An attempt is only made when the ESC could actually act on one — the link has been up long enough for the ESC to have finished booting, the tester is disarmed, the motor is stopped, and no other command is on the wire. This matters because a DShot command is only executed after arriving in a run of identical frames, and an attempt made at the wrong moment is one thrown away.

If the chip stays red with an ESC that you know supports EDT, see Troubleshooting.

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The optional third wire

Most ESCs have a telemetry pad that streams a 10-byte frame on request at 115200 baud. Wiring it up buys you finer voltage and current, and consumed mAh.

	2.0" board	2.8" board
Telemetry RX	GP5 — P1 header, pin 10	GP28 — J4 pin 11

It is receive-only — the board never drives that line — and any free GPIO will do. Enable it under CFG → SETUP → KISS TELEM and set the pin below it. The pin stepper skips past whichever pin the ESC signal is on, so the two cannot collide.

If the wire is unplugged mid-session, the tags drop back to EDT and the readouts get coarser. They do not freeze on the last fine value, for the same reason the tiles blank: a steady, precise number from a sensor that stopped reporting is the worst of both.

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LINK, and what a bad one looks like

998/S with 0% ERR is a healthy 1 kHz link. The error percentage turns amber above 5 %.

A poor link usually means the signal wire: too long, unshielded, or run beside something noisy. Shorten it first. If that is not possible, drop DSHOT KBAUD to 300 in SETUP — the LINK row on that screen updates live, so you can see the effect without leaving the page.