Scout
The blue MINDSTORMS brick from the Robotics Discovery Set (9735, 1999): an LCD, four buttons, two touch inputs, two motor outputs, a light sensor, indicator LEDs and six AA cells. It hears the same 38 kHz infrared link as the RCX, and its light sensor decodes VLL on top of that.
Reach
| Capability | State | Note |
|---|---|---|
| Motors A and B over infrared | works | no program has to be running; an infrared LED sending the remote's frames drove a real Scout at good range |
| Built-in behaviours on the Msg keys | works | Msg 1 seek dark, Msg 2 seek light, Msg 3 bug dance |
| VLL out on the Motor C output | works, untested here | C is a red LED, not a motor: C up and C down send VLL forward and reverse, so a remote reaches a Micro Scout through the Scout |
| VLL in on the light sensor | works, untested here | the same 7-bit code set the Micro Scout uses |
| Programs written on the brick | works, untested here | the LCD and four buttons program it with no computer in the room |
| Download and live control from a computer | works, untested here | over the 9713 serial or 9783 USB tower |
| One VLL command from a running program | works, untested here | the SDK vll opcode carries one 7-bit value |
| Stop and Sound keys of the remote | unknown | plausible on a Scout, never confirmed |
| Program keys P1 to P5 | unknown | the Scout holds one program slot, not five, so no mapping is obvious |
What it hears
Infrared is the main channel and it is RCX-class: the same link layer the RCX uses, so the IR tower and the handheld LEGO Remote Control (9738) both reach it. Frames, timings and opcodes are in RCX IR protocol, and the Scout column of the button map, key by key, is in LEGO Remote Control (9738). The early-firmware bug that made C-reverse unreliable on an RCX never applied here, because on a Scout C is the lamp rather than a motor.
Light is the second channel, and it runs both ways. The sensor drives the brick's own behaviour — a light-change alarm, firing a dart — and it decodes VLL, the same code set as the Micro Scout (VLL opcode table). Outward, a red LED on the Motor C output sends VLL, and LEGO named this as one of the sanctioned ways to fill a Micro Scout's P slot (LEGO FAQ — P program & IR tower). It is the only brick that both reads light and flashes it with nothing added, so a Scout can command a Micro Scout on its own.
Reaching it today
- The bridge. Flash Force ships the 9738 remote as a library layout and sends its frames through the bridge. Aim at the Scout's middle infrared port, not at the light sensor, with the brick idle and its options off; replicated at good range with an infrared LED.
- The handheld remote itself, if you own one. It drives a Scout with no program running: A and B are the two real motors, C is the VLL lamp.
- From a computer. NQC and BricxCC download programs over the tower and also drive the brick live — BricxCC's Direct Control panel is a remote control in software. The serial tower 9713 plugs into a computer's 9-pin port and the USB 9783 works too; the 9-pin belongs to the tower, not to any cable reaching the brick. The older path is the Scout SDK,
ScoutTool.exeandScoutDOS.exewriting LASM — see pbrick.info and LEGO official docs — Tower Interface + Scout SDK. ROBOLAB covers the brick too. - On the brick. The LCD and buttons pick from roughly 3000 command combinations with no computer involved.
Links
- Set 9735 Robotics Discovery Set — Sets & bricks index · Rebrickable.
- Part 32104c01 (Rebrickable).
- The
vllopcode, the tower download path and the VLL code set: Scout SDK, November 1999. - NQC targets RCX, CyberMaster and Scout. ROBOLAB covers it too.
- Motor C as the VLL lamp: O Falcão, ofalcao.pt · Mike Kollross, news.lugnet.com.