Brainbox Serial Protocol Reference

The Brainbox receives data from Podcatcher devices over BLE and exposes it as CSV frames on a USB serial connection. Interactive installations, kiosks, and custom software can read these frames to react to visitor actions in real time.

Physical connection

Parameter	Value
Interface	USB Serial (CDC)
Line delimiter	\r\n (CR+LF)
USB Vendor ID	0x2dcf
USB Product ID	0x6003

Connect the Brainbox to a computer via USB. It appears as a standard serial (COM) port — no special drivers are required on modern operating systems.

Console commands

After opening the serial port, activate the Brainbox console and enable the frame types you need:

<CR>                        ← send a carriage return (0x0D), wait 300 ms
console tracking 1<CR>      ← enable Tracking V2 frames, wait 200 ms
console interactive 1<CR>   ← enable Interactive V1 frames, wait 200 ms
version<CR>                 ← response: "version: 2.5.1"

Tip

<CR> means a single carriage return character (hex 0x0D). In most serial terminals this is just pressing Enter. In code, send \r (e.g. serial.write("console tracking 1\r") in Python).

Available commands

Command	Function
console tracking 1	Enable Tracking V2 output
console tracking 0	Disable Tracking V2 output
console interactive 1	Enable Interactive V1 output
console interactive 0	Disable Interactive V1 output
console syncdock 1	Enable Basecamp frames (not yet in firmware — see AVS-147)
version	Query firmware version
help	List all available commands

Note

Console responses such as version:, console *:, ble, BLE scan:, serial:, Sync OK, Brainbox, tracking:, error, and ok are not data frames — your parser should ignore them.

Content structure in the CMS

To understand the frame data, it helps to know how content is organized in the Guide-ID CMS:

Site
 └── Tour
      └── Stop
           └── Clip (audio file + optional Interactive Clip Id)

• A site has one or more tours
• A tour contains one or more stops
• A stop contains one or more clips — a clip is the actual content, typically with an audio file linked to it
• Each clip has an optional Interactive Clip Id (1–65535) that uniquely identifies it for interactive setups

The clipIdUser value in the frames below corresponds to this Interactive Clip Id. You configure it per clip in the CMS under the clip settings.

How clips get triggered

A clip starts playing on the Podcatcher in one of these ways:

• Beacon scan — the visitor manually scans a beacon at a stop
• UWB auto-trigger — the visitor enters a zone and the Podcatcher triggers automatically based on proximity (UWB distance)
• Clip flow navigation — the visitor presses buttons (Up, Down, Left, Right) to navigate through the clip flow within a stop (e.g. choice clips with multiple branches)

Each time a clip starts, the Brainbox sends a frame with the corresponding Interactive Clip Id — regardless of how the clip was triggered.

BLE frame types

All frames arrive as CSV lines over serial. The first field (version byte) determines the frame type.

Tracking V2 — version 66 (0x42)

Sent approximately once per second for each device in range. Use this for real-time visitor position tracking, battery monitoring, and button state.

66,pp009071,0xA1B2C3D4E5F60718,1001,150,3700,0x0004,0x0000

#	Field	Type	Example	Description
0	version	decimal	66	Always 66
1	deviceSerial	string	pp009071	Podcatcher serial number (pp + 6 digits)
2	visitorId	hex	0xA1B2C3D4E5F60718	16 hex chars (8 bytes) — 0x0000000000000000 = idle
3	clipIdUser	decimal	1001	Interactive Clip Id of last activated clip (0 = none)
4	lastTriggerDistance	decimal	150	UWB distance in cm (0 = no trigger)
5	batteryMv	decimal	3700	Battery voltage in mV
6	keysLast	hex	0x0004	Last pressed buttons (bitmask)
7	keysHeld	hex	0x0000	Currently held buttons (bitmask)

Caution

Fields 6 and 7 (keysLast, keysHeld) are hexadecimal encoded — note the 0x prefix in the output. All other numeric fields are decimal.

Button bitmasks

Bit	Hex	Button	Description
0	0x0001	Down	Button down
1	0x0002	Right	Button right
2	0x0004	Center	Button center
3	0x0008	Up	Button up
4	0x0010	Left	Button left
12	0x1000	Volume Up	Increase volume one step
13	0x2000	Volume Down	Decrease volume one step

Interactive V1 — version 161 (0xA1)

Sent every time a clip starts playing on a Podcatcher — whether triggered by a beacon scan, UWB auto-trigger, or clip flow navigation. Each frame tells you:

• Which device triggered (deviceSerial)
• Which visitor is using it (visitorId — unique per session)
• Which language they selected (NL, EN, DE, FR, ES, IT)
• Which clip was triggered (clipIdUser — the Interactive Clip Id configured in the CMS)
• Which armed code was set by the Podcatcher (requestedVideoCode — usually an AV-Sync video code)
• How many triggers this visitor has had so far (sequence)

161,pp009071,A1B2C3D4E5F60718,2005,EN,7,0x0000001A

#	Field	Type	Example	Description
0	version	decimal	161	161 or 160 (both accepted)
1	deviceSerial	string	pp009071	Podcatcher serial number
2	visitorId	hex	0xA1B2C3D4E5F60718	Visitor ID (unique per session)
3	clipIdUser	decimal	2005	Interactive Clip Id of triggered clip
4	language	string	EN	2-character language code from the trigger file (NL, EN, DE, FR, ES, IT)
5	sequence	decimal	7	Counter that increments per trigger, rolls over after 255
6	requestedVideoCode	hex	0x0000001A	Armed code — usually an AV-Sync video code (0x00000000 = none)

Example: interactive display scenario

A visitor walks past an interactive display with their Podcatcher. The display receives:

161,pp009071,0xA1B2C3D4E5F60718,2005,EN,7,0x0000001A

The display now knows instantly:

• Visitor 0xA1B2C3D4E5F60718 → recognizable at the next display too
• Language is English → show English subtitles or text
• Clip 2005 → play the matching animation
• Armed code 0x1A → play the AV-Sync video assigned to this stop
• Trigger #7 → visitor has been active for a while, adapt content accordingly

Use cases for interactives

Automatic language adaptation The visitor selects their language on the Podcatcher. Every display in the museum adapts automatically — no touchscreen or language button needed on the display itself.

Visitor recognition across rooms The visitorId persists throughout the entire visit. A visitor triggers a display in room A, then walks to room B — the display there recognizes the same visitorId and can personalize: “Welcome back, you previously saw…” No login or QR scan required.

Interactive projections and animations A Podcatcher comes in range → the projection starts automatically. Multiple visitors at once? Your application sees all active visitorId values in the zone and can adapt content to the number of visitors (solo experience vs. group experience).

AV-sync with external displays When a visitor triggers a stop, the Podcatcher arms a code (usually an AV-Sync video code). This requestedVideoCode is sent via the interactive frame. The connected display matches the armed code and plays the corresponding content — no additional hardware (tablet, touchscreen) needed.

Debugging interactive installations

When developing an interactive installation, use a serial monitor to:

• Live debug: See frames arriving in real time as you stand in front of the display
• Test language switching: Change language on the Podcatcher, verify the display reacts
• Check timing: Frames arrive within 1 second of the beacon trigger
• Multi-visitor testing: Test with 2–3 Podcatchers simultaneously and observe all visitorId values

Related articles

• Understanding the Brainbox — what the Brainbox does and how it works
• AV-Sync Setup — configure synchronized audio-visual playback