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30 Years of the BBC Micro
Alioth writes "The BBC has an article on the BBC Microcomputer, designed and manufactured by Acorn Computers for the BBC's Computer Literacy project. It is now 30 years since the first BBC Micro came out — a machine with a 2 MHz 6502 — remarkably fast for its day; the Commodore machines at the time only ran at 1MHz. While most U.S. readers will never have heard of the BBC Micro, the BBC's Computer Literacy project has had a huge impact worldwide since the ARM (originally meaning 'Acorn Risc Machine') was designed for the follow-on version of the BBC Micro, the Archimedes, also sold under the BBC Microcomputer label by Acorn. The original ARM CPU was specified in just over 800 lines of BBC BASIC. The ARM CPU now outsells all other CPU architectures put together. The BBC Micro has arguably been the most influential 8 bit computer the world had thanks to its success creating the seed for the ARM, even if the 'Beeb' was not well known outside of the UK."
The first computer I ever used was a BBC Micro. It was around 1986 in a small private boarding school in the middle of the bush in Zambia. We were over an hour's drive from the nearest telephone. The school got one or two of these computers just before I left, and somehow they got me hooked on computers.
The only command I still remember was that you had to type "CHAIN" to run something. I've been curiours about that command ever since, but a quick Google search leads me to believe that it "chained" the LOAD and RUN commands together.
www.clarke.ca
Not to worry! Thanks to the power of javascript and web2.0, you can again await the day when we'll be able to push a 6502 into the realm of the megahertz!
(Please note, above linked project is actually pretty fucking cool: "In the summer of 2009, working from a single 6502, we exposed the silicon die, photographed its surface at high resolution and also photographed its substrate. Using these two highly detailed aligned photographs, we created vector polygon models of each of the chip's physical components - about 20,000 of them in total for the 6502. These components form circuits in a few simple ways according to how they contact each other, so by intersecting our polygons, we were able to create a complete digital model and transistor-level simulation of the chip.
This model is very accurate and can run classic 6502 programs, including Atari games. By rendering our polygons with colors corresponding to their 'high' or 'low' logic state, we can show, visually, exactly how the chip operates: how it reads data and instructions from memory, how its registers and internal busses operate, and how toggling a single input pin (the 'clock') on and off drives the entire chip to step through a program and get things done."
It is, however, the case that this might not be the fastest way to execute 6502 instructions...)
Changing the screen mode 3/4 of the way down each screen refresh. Programming while counting every clock cycle - fantastic. I still wonder where all the resources are wasted in current software. I still say FRAK! when the need arises. Nobody knows what I'm talking about :(
Ah, someone with brains. If it still works, why would you change it (concerns about suitable replacement being timely aside as that's a separate issue).
BBC's were great for all sorts of things. Working in school IT departments I often find them, and sometimes I find "old" staff there who tell me how they used them for EEPROM reading/programming, and other interfacing that today's school machines hardly do any more with specialist adaptors.
They even ran the Teletext service in the UK (they actually have a "Teletext" video mode on them) and all sorts. It was a programmable, extendable computer that did what was necessary and no more.
Oh for those days again. Here's hoping that Raspberry Pi thing takes off.
What Braben and Bell did to get this running on the BBC makes for pretty interesting reading.
http://en.wikipedia.org/wiki/Elite_(video_game)#Technical_innovations
Summation 2
What the 6502 in the C64 (and the BBC Micro, under discussion) had which most people who started asm on the Z80 missed was the zero page. Effectively, using the zero page you had 256 registers. Zero page operations on the 6502 were as fast as register operations on the Z80. While I'm much more proficient at Z80 asm than 6502, I really appreciate the very straightforward and uncomplicated - but powerful - design of the 6502.
Oolite: Elite-like game. For Mac, Linux and Windows