Micro Scout
A brick the size of a matchbox with a motor, a speaker and a light sensor built into it, sold in 1999 and 2000 in two Star Wars sets, the Droid Developer Kit (9748) and the Dark Side Developer Kit (9754). It hears one link and only one: VLL, light switched plainly on and off at the sensor on its top, and it carries no radio at all.
Reach
| Capability | State | Note |
|---|---|---|
| Seven fixed programs, cycled by the button | works | One Direction, Two Directions, Light Follower, Light Control, Standby, Alarm, Handshake; slots 3 (Seek Light) and 7 (Code) verified against elecbrick, the middle names are the commonly cited set; none of them can be overwritten or erased |
| Motor forward and reverse | works | direct codes 0 and 1 |
| Beeps 1 to 5 | works | direct codes 4 to 8 |
| The empty P slot: store a program of up to 15 steps, then run it | works | delete, then script steps, then run |
| Reading a whole frame off invisible infrared | works | the sensor has no infrared-cut filter; 30 to 40 cm on direct aim |
| Stopping the motor with a direct code | documented, no effect on device | code 10, in both the Scout SDK and rcxvll.nqh; the older 15 from elecbrick is in no official list; neither one moved the brick |
| "Next" and Reset | documented, no effect on device | codes 70 and 71, real and documented in the Scout SDK and on the printable barcode card |
| Codes 2, 3, 9 and 11 to 14 | unknown | unused or unlisted for this brick, whatever they do on its relatives |
| The application LEGO promised for the P slot | out of reach | a "future application (fall 2000)" that was to arrive through the RIS 2.0 tower, and never shipped |
| Programming it from the kit's own CD | out of reach | the disc carries no VLL class and no port access at all |
What it hears
One sensor on top does both jobs: it reads brightness for the built-in programs, and it decodes VLL for the P slot. The link has no carrier and runs one way, so nothing ever comes back out of the brick. The frame, the bit encoding and the checksum are in VLL — Visible Light Link; the code values are in VLL opcode table.
The sensor has no infrared-cut filter, so it takes a frame off an infrared diode as happily as off visible light. What it will not take is light chopped by a carrier. LEGO's own tower therefore sent VLL on a visible red LED: its 940 nm channel was already spoken for by the RCX serial link, which is modulated and so useless for VLL. Drive infrared with plain on and off timing instead and it works, which is why the old serial-only tower never reached this brick.
Reaching it today
Least effort first.
- Phone torch (Flash Force) — a phone, and nothing else at all.
- Powered Up hub (Pybricks VLL) — a hub's own LED, steadier than a torch because the timing runs on the hub rather than in a browser.
- The bridge — the same frame on invisible infrared, at range, with nothing to watch.
- lego-blockly or an infrared diode driven baseband — timing you can rely on, from a desktop.
Which link this is and what else hears it: How the links work.
Links
- Sets 9748 Droid Developer Kit (white brick) and 9754 Dark Side Developer Kit (grey) — Sets & bricks index.
- Part 32344c01 (Rebrickable).
- What the P slot was for, in LEGO's own words: LEGO FAQ — P program & IR tower.
- The code list, and codes 10, 70 and 71: Scout SDK, VLL Command Set table, November 1999.
- Why the kit's disc could never fill it: Droid Developer Kit CD (_ddk.exe).
- Adafruit, Bluetooth remote for the Droid: learn.adafruit.com.
- Printable build instructions for the kit models: Buildable models (DDK & DSDK).