The Smart Box is a general purpose control interface for use with a wide range of computers found in education in the early 1990s. These computers include the BBC Microcomputer, the Acorn Archimedes range, Apple Macintosh computers, the Research Machines 480Z range and IBM PC-compatible computers. This particular model was for use with an IBM PC-compatible computer.

The box provides the following facilities;

  • 8 digital outputs, which are active low, that is they sink current, and which can handle 35mA per bit maximum. Each output bit can be individually set.
  • 8 digital inputs, which are active high and which can be individually tested.
  • 4 Analogue ports to which a range of sensors may be attached. Each sensor has a unique ID, which is used to identify it to the Smart Move program.
  • 4 outputs for bi-directional motor control.
  • a serial interface working at 9600 baud for connection to the host computer system.



The following pictures show the outside appearance of the SB-01


Top view

Side and back panel views

The label on the underside showing the box variant ID and the serial number.




Internally the device is very well constructed and is based on the 6502 microprocessor.


Power is provided from the 240v AC mains through a fused 'kettle plug'. The circular component is a toroidal transformer which provides the low voltage to the system. The case is earthed though the outputs are floating.

The motherboard occupies most of the top part of the case. The power supply components are in the top right corner. The serial input socket is at the top and is a 240 5-pin DIN socket. To the right of the serial socket is the reset push switch.

To the right are the four, black, 180 5-pin DIN, analogue sensor sockets. The red and yellow sockets inside are for the digital sensors. To the left are the eight, white motor outputs and the sockets for the digital outputs, red and blue. Between the digital output sockets is a double row of power transistors for motor control.

This is an issue 3 motherboard.

The CPU is a 65C02 and to the left of it is an 8K EPROM of type 2764, which holds the box Operating Sytem (OS). Of this 8K only 4K is actually used by the OS. To the left of the EPROM is a 32K static RAM and immediately below that a 6522 VIA for digital input and output. The analogue ports are read by a 7002 ADC chip. These major ICs are identical to those found in the BBC Master.



The control box is managed by a piece of software called SmartMove on the PC. The supplied 3" disk contains two important files;

  1. SMART.EXE - is a DOS-based program that displays and manages the interface and which uploads the interpreter for the built-in programming language.
  2. AL.COD - is a 6502 machine code program that is uploaded by SMART.EXE. It is the interpreter for the control programming language and allows fast interaction with the box's electronics.

This software can be downloaded here.

SmartMove for the BBC Master is available here.



The Smart Box version SB-01 communicates with the host computer via a serial interface running at 9600 baud. The communication protocols can be found in this document, which appears to be an extract from the Smart Box OS manual. The document contains a number of errors and omissions;

  • command #43 in the document does not exist; command #23 should be used instead for the same function,
  • command #29 is shown as command #28. The second entry for command #28 is actually for command #29
  • commands #14 and #21 have detail about their functions omitted. These commands allow PWR control of the motors and the digital outputs.



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