These two hand-made books and mostly hand-written maybe considered the day when everything started 36 years ago. This is the reason I saved them from tenth of movings, from home to home, town to town and then country to country. It was the second half of the '70s when, already studying chemistry I have started the dream to have something like a computer. Then the day arrived at the end of the summer of '79 (just ten years afte the Summer of '69 
) after three months of work to buy the Rockwell AIM65
The choice was done! I preferred to put the hand on a development board, very well equipped and documented instead of moving to the first Commodore and Sinclair devices that started also during these years.
These days I paid the system 684.000 Italian lira, equivalent to the actual date value of 2.029,00 Euros! It was an absolutely incredible price and it will be today if a development platform will cost so, but thanks to this stuff I had the opportunity to play and study for years.
I remember that the real difficult in that years was to find from Italy any sort of documentation; the fastest way to find something was to ask for a fax when you was almost luck to find some importer or company open to cooperate. And electronic components and companies was few and very difficult to contact. One of the better ways it was always possible to count on especially for searching products and non conventional components was just the BBC that until the '90s had a big shop in Turin where I was living in those years.
When the AIM65 arrived
In autumn of 1979 the local importer received the AIM65 I ordered, after spending entire season reading any review it was possible to find in Italy from USA newspapers; who don't remember the famous BYTE monthly review, the during the next decade was reprinted for a period in a Italian version with localised articles (and I had the honour to write a lot for them in that period) ?
The package was just the bare unit, a BBC desktop power supply bought separately while waiting the shipment from Rockwell USA and some kilograms of paper.
How the fascinating system shown when unpacked |
The SYSTEM65 documentation package: circuits, schematics, software and hardware samples and more. |
A lot of paper with useful information, circuits and schematics, sample applications and assembler software example (for manual copy) |
A very well detailed manual on the CPU registers, instruction set and all the possible usage, including a lot of how-to specific of the board |
The board immediately captured my imagination. Very well engineered was studied just to experiment al the features of the 6502 microprocessor, including a graphic thermal printer (with controller schematics and source), 20 characters LED alphanumeric display and two EEPROM for free use. A very powerful 2 pass assembler and two 8 bit GPIO ports directly accessible. The system was completed with a full QWERTY keyboard making a system that was unique for the period.
Programming and controlling the machine
As always happens, I started with very simple projects, like blinking a led, using the I/O programmable ports to control relays to power brush motors and so on.
The image below shows a piece of paper saved in the documentation book; how to use 8 bytes I/O port to control an hexadecimal keyboard acquisition (and also in this case it was a BBC cheap mechanical HEX keyboard).
Then projects evolved; one of the most satisfactory creations was processing data from the AIM65 EEPROM available slot with the pre-encoded phonemes to drive an external Texas Instruments processor of the series TMS. One of the first language synthesis approaches (then abandoned leaving space to the modern voice synthesis software) that required about six months to be setup.
Was always hard to program anything, including some basic elements that in the actual days we consider something obvious.
The approach was hard also to create a simple custom character set for the printer. The images below shows the byte-to byte character design:
And, as you can see, when I say design I mean design The further step was the creation of the assembly code where the unique - but great - advantage was the use of symbolic names for variables and routines calls (aka functions, in the modern informatics). Time has passed, but some thermal printer listing has survived anyway. Scanner? No, thanks, photocopy!
After that magic summer of '79 dreaming this machine and the next years playing and discovering so many things with it a lot of things occurred. This remain anyway the very first starting point when the digital world met my life.
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