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The Concept Keyboard Company A4-128 Keyboard

[Index by function  ]     [Index by Company ]

Concept Keyboard A4-128 keyboard top

 Concept Keyboard A4-128 Keyboard (top)

Concept Keyboard A4-128 Keyboard back

  Concept Keyboard A4-128 Keyboard (back)

Concept Keyboard A4-128 bottom

 Concept Keyboard A4-128 Keyboard (bottom) 

This Concept keyboard is designed for the BBC Microcomputer and connects to the User Port. A cable is provided to connect the port on the back to the BBC Microcomputer's User Port.

The Concept keyboard was originally designed for the BBC Micro, having a touch sensitive membrane panel typically with 128 squares labeled 00 - 128. The keyboard connects to the BBC Micro user port and can also be connected to the RM Nimbus and Acorn Archimedes with optional user ports. The original keyboard was available in 2 sizes A4 or A3. The example that I have is the A4-128. The original models are identified by their blue metal surround. Later models, the Concept Universal and Universal Plus include a serial port as well as user port connection to provide broader compatibility.

Primarily used in education for very young children or children with special needs. There is a wide range of educational software particularly for the BBC Micro that makes use of the Concept keyboard. The concept keyboard could also be found in use for special scientific applications, industrial applications and display terminals where the computers keyboard was not a desirable input method. A paper or plastic overlay is typically used to provide a user friendly interface.

INTERFACE PIN OUT
A 25 pin D type connector is used on the concept keyboard with the following connections.

  1. USER PAD
  2. USER PAD
  3. DATA BIT 7 (MOST SIGNIFICANT BIT)
  4. NOT USED
  5. SYSTEM GROUND 0v
  6. DATA BIT 6
  7. DATA BIT 5
  8. DATA BIT 4
  9. DATA BIT 3
  10. DATA BIT 2
  11. DATA BIT 1
  12. DATA BIT 0 (LEAST SIGNIFICANT BIT)
  13. NEGATIVE STROBE
  14. POSITIVE STROBE
  15. RS422 OUT A
  16. RS422 OUT B
  17. RS232C/V24
  18. CURRENT LOOP POSITIVE
  19. CURRENT LOOP NEGATIVE
  20. RS 423
  21. NOT USED
  22. NOT USED
  23. NOT USED
  24. UNREGULATED INPUT 8 TO 12V
  25. +5v SUPPLY +/- 0.25v

In May 1985 Acorn User published a comparative review titled "A new breed of Keyboards "

Here is the Installation Guide for the Concept A3-128, A4-128 Keyboards.
Here is the Concept Keyboard User Registration Form .