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wanted the history of the daughterboard hobbymadetheirown

By lawrephord214 ·
all people that made their own design if you know
of anyone ? write about them here please ? i sent
a sketch to an engineering company ! could this interface be changed to edit sketches ?
.................................................
\.....static ram slot .........................\
.\.....dynamic ram slot.........................\
..\.....rom operating system.....................\
...\.....rom basic language...................\
....\.....rom database.........................\
.....\.....rom spreadsheet......................\
eight slots this side
other side
eight more
./.lan card...................................../
../..net ring card............................../
.../..4 lan cards.............................../
..../...4 modem cards.........................../
.
.
anybody do anything similar in the early 1980's ?
PLEASE WRITE IT UP HERE ?
lawrephord214@hotmail.com

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Confusing Post!

by GuruOfDos In reply to wanted the history of the ...

From what I can gether, you are asking if anybody 'built their own' computer back in the 1980s.

Well I certainly did. I also built my own peripherals for many home computers of the time, allowing them to do a lot more than just play games.

Commodore Vic20: Ram upgrades, digital input/output cards, D-A and A-D converters, X-Y plotters.

Sinclair (Timex) Spectrum:Joystick Interfaces, RS232 interfaces, EPROM Programmer, Video Digitiser and Frame Grabber, floppy drive controller, light pen.

I also built my own modular computer system using the legendary Zilog Z80 8 bit processor. What started off as a simple 2MHz Z80 development system with a hex LED display and hex keypad ended up as a full 6U x 84HP dual 19" rack with all manner of 'goodies' which could be plugged in or out as required....and were 'hot swappable' too!

I ended up with a system which used segmented memory so that the 64k address space of the Z80 could be expanded by paging right up to 512kb. Several graphics controllers, including video overlay so that I could 'title' live video (for time and date stamping of security cameras), mix video signals together and a three axis motion controller (for animation recording). Not to mention 512 lines of memory-mapped digital IO for controlling all sorts of goodies.

I also wrote my own monitor programme and various function modules which ended up in ROM and could be strung together as libraries for complex routines. I even went as far as developing a rudimentary interpreted 'language' which was similar to BASIC. I cribbed much of it from Commodore BASIC and dubbed it FLAME, which stood for Flexible Language And Modular Extensions) with a whole host of extra commands and functions which could be added to by dreaming up another 'keyword' and adding it to the interpreter library.

By adding additional Z80 processor cards to certain slots in the rack and linking them via a high speed (lol....this was 1981!!!) shared multi-port memory area, then up to 4 processors could multitask.

When IBM PC-AT's became popular, I then added an interface which converted the Z80 processor bus to an emulation of the ISA bus allowing early 8 bit ISA cards to be plugged in to a daughterboard, so that almost anything that could be done on an IBM could be done on this. Slower, I admit, but 4 parallel Z80B CPU's running at 3.276MHz could often outperform a 286-12! I'd then mess around with assembly language to disassemble PC ROM and BIOS routines and 'rewrite' them in Z80 assembler so that the cards would work on my system, using programming calls similar to DOS INT routines.

To this day, I still fire the beast up and tinker with it, just to keep my electronic skills in tune more than anything else.

Of course, all computers HAD to have a name back then...it was EXPECTED!!! I wasn't going to go down the road of just using some word or other like most home computer manufacturers did back then. Spectrum, Atmos, Electron, Dragon and such like were not for me. It had to be an acronym (the sillier the better, and preferably RUDE...well, I WAS only 14!).

It was most entertaining to see the looks on people's faces when I offered to show them my ***** (Programmable Electronic Numeric Information System)!!!

What you have to remember is that back then, computers WERE the realm of big business or the dedicated electronics hobbyist. I cut my teeth on electronics long before computers became mainstream, and my early forays into computers were as an electronics engineer. To this day, I'm still more interested in building 'add-ons' and interfaces than I am in word-processing or playing games.

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What kind of a name is that?

by AusMentalCase In reply to Confusing Post!

I suppose with a name like ***** you must be a cocky *******!

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