Microprocessor development board

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Photo of two experimenter boards for the MSP430 chipset by Texas Instruments. On the left the larger chip version, on the right a small version in USB format. MSP430-experimenter boards.jpg
Photo of two experimenter boards for the MSP430 chipset by Texas Instruments. On the left the larger chip version, on the right a small version in USB format.

A microprocessor development board is a printed circuit board containing a microprocessor and the minimal support logic needed for an electronic engineer or any person who wants to become acquainted with the microprocessor on the board and to learn to program it. It also served users of the microprocessor as a method to prototype applications in products.

Contents

Unlike a general-purpose system such as a home computer, usually a development board contains little or no hardware dedicated to a user interface. It will have some provision to accept and run a user-supplied program, such as downloading a program through a serial port to flash memory, or some form of programmable memory in a socket in earlier systems.

History

The reason for the existence of a development board was solely to provide a system for learning to use a new microprocessor, not for entertainment, so everything superfluous was left out to keep costs down. Even an enclosure was not supplied, nor a power supply. This is because the board would only be used in a "laboratory" environment so it did not need an enclosure, and the board could be powered by a typical bench power supply already available to an electronic engineer.

Microprocessor training development kits were not always produced by microprocessor manufacturers. Many systems that can be classified as microprocessor development kits were produced by third parties, one example is the Sinclair MK14, which was inspired by the official SC/MP development board from National Semiconductor, the "NS introkit". [1]

Although these development boards were not designed for hobbyists, they were often bought by them because they were the earliest cheap microcomputer devices available. They often added all kinds of expansions, such as more memory, a video interface etc. It was very popular to use (or write) an implementation of Tiny Basic. The most popular microprocessor board, the KIM-1, received the most attention from the hobby community, because it was much cheaper than most other development boards, and more software was available for it (Tiny Basic, games, assemblers), and cheap expansion cards to add more memory or other functionality. [2] More articles were published in magazines like "Kilobaud Microcomputing" that described home-brew software and hardware for the KIM-1 than for other development boards. [3]

Today some chip producers still release "test boards" to demonstrate their chips, and to use them as a "reference design". Their significance these days is much smaller than it was in the days that such boards, (the KIM-1 being the canonical example) were the only low cost way to get "hands-on" acquainted with microprocessors..

Features

The most important feature of the microprocessor development board was the ROM-based built-in machine language monitor, or "debugger" as it was also sometimes called. Often the name of the board was related to the name of this monitor program, for example the name of the monitor program of the KIM-1 was "Keyboard Input Monitor", because the ROM-based software allowed entry of programs without the rows of cumbersome toggle switches that older systems used. The popular Motorola 6800-based systems often used a monitor with a name with the word "bug" for "debugger" in it, for example the popular "MIKBUG". [4]

Input was normally done with a hexadecimal keyboard, using a machine language monitor program, and the display only consisted of a 7-segment display. Backup storage of written assembler programs was primitive: only a cassette type interface was typically provided, or the serial Teletype interface was used to read (or punch) a papertape. [5]

Often the board has some kind to expansion connector that brought out all the necessary CPU signals, so that an engineer could build and test an experimental interface or other electronic device.

External interfaces on the bare board were often limited to a single RS-232 or current loop serial port, so a terminal, printer, or Teletype could be connected.

List of historical development boards

Dragon12-P Freescale HCS12/9S12 microcontroller trainer, an All-In-One EVB, EVBU and project development board Drago12P 68HC12 EVB.jpg
Dragon12-P Freescale HCS12/9S12 microcontroller trainer, an All-In-One EVB, EVBU and project development board

DSP evaluation boards

A DSP evaluation board, sometimes also known as a DSP starter kit (DSK) or a DSP evaluation module, is an electronic board with a digital signal processor used for experiments, evaluation and development. [6] Applications are developed in DSP Starter Kits using software usually referred as an integrated development environment (IDE). [7] Texas Instruments and Spectrum Digital are two companies who produce these kits.

Two examples are the DSK 6416 by Texas Instruments, [8] based on the TMS320C6416 fixed point digital signal processor, a member of C6000 series of processors that is based on VelociTI.2 architecture, [9] and the DSK 6713 by Texas Instruments, which was developed in cooperation with Spectrum Digital, based on the TMS320C6713 32-bit floating point digital signal processor, [9] :3 which allows for programming in C and assembly.

See also

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References

  1. http://www.old-computers.com/MUSEUM/computer.asp?st=1&c=1147 Archived 2010-11-21 at the Wayback Machine description of the National Semiconductor introkit
  2. http://oldcomputers.net/kim1.html KIM was very popular with hobbyists
  3. why Kilobaud published KIM software
  4. "The MEK6800D2 system with MIKBUG". Archived from the original on 1 October 2011.
  5. http://retro.hansotten.nl/index.php?page=micro-kim Micro-KIM is a retro remake of the KIM for which many programs are available that were originally released on papertape
  6. "DSP Starter Kits". DSP. Kane Computing. Archived from the original on 3 December 2013. Retrieved 23 April 2012.
  7. Robert Oshana (29 September 2005). DSP Software Development Techniques for Embedded and Real-Time Systems. Newnes. p. 384. ISBN   978-0750677592 . Retrieved 23 April 2012.
  8. IEEE Nuclear Science Symposium Conference Record 2004. Rome: Institute of Electrical and Electronics Engineers. 2004. p. 4161. ISBN   978-0780387003 . Retrieved 23 April 2012.
  9. 1 2 Rulph Chassaing (13 December 2004). Digital Signal Processing and Applications with the C6713 and C6416 DSK. Wiley-Interscience. p. 497. ISBN   978-0471690078 . Retrieved 23 April 2012.