04-29-2017, 03:30 AM
04-29-2017, 11:23 AM
I'd take the beautiful case if it were available.
No need for a dediacted PCB since a Pi can easily emulate the Speccy, but good keyboards are not easy to come by. I used to own one for my Spectrum in the 80th, but sold everything.
Did you know the Spectrum was able to evaluate formulas stored in strings? Very powerful BASIC with full control over the display and a nice manual ... killer features for us kids who loved programming!
Thanks for sharing :-).
No need for a dediacted PCB since a Pi can easily emulate the Speccy, but good keyboards are not easy to come by. I used to own one for my Spectrum in the 80th, but sold everything.
Did you know the Spectrum was able to evaluate formulas stored in strings? Very powerful BASIC with full control over the display and a nice manual ... killer features for us kids who loved programming!
Thanks for sharing :-).
04-29-2017, 05:54 PM
It is 35 years this month since the Spectrum was launched.
When I heard of an earlier remake, I had a look to see how it might fit on the HP Prime's screen.
http://www.hpmuseum.org/forum/thread-7611.html
In the specs I have seen, the number of lines varies - I am not aware of any specific upgrade associated with the change, so perhaps it just varies according to whether the documentation assumes you are using NTSC or PAL?
When I heard of an earlier remake, I had a look to see how it might fit on the HP Prime's screen.
http://www.hpmuseum.org/forum/thread-7611.html
In the specs I have seen, the number of lines varies - I am not aware of any specific upgrade associated with the change, so perhaps it just varies according to whether the documentation assumes you are using NTSC or PAL?
05-02-2017, 09:54 AM
The ZX-81 is the machine that I cut my programming teeth on so when the "Speccy" came out I couldn't resist making it my own by customising a load of things on it.
First thing I did was write a Z80 assembler/disassembler in BASIC. I then used it to rewrite it in assembly language and promptly disassembled the on-board ROM.
With the information I had from that, I first accelerated the tape I/O about threefold. I also ripped out the disk I/O section knowing that I would never need it and used the space freed up to rewrite the floating point arithmetic routines and replace the awful 40-bit "precision" (I use that term loosely) ones with my own custom-built 64-bit precision.
All of these alterations were burned to an EEPROM that I mounted in place of the original ROM in the machine.
Those were the days!
First thing I did was write a Z80 assembler/disassembler in BASIC. I then used it to rewrite it in assembly language and promptly disassembled the on-board ROM.
With the information I had from that, I first accelerated the tape I/O about threefold. I also ripped out the disk I/O section knowing that I would never need it and used the space freed up to rewrite the floating point arithmetic routines and replace the awful 40-bit "precision" (I use that term loosely) ones with my own custom-built 64-bit precision.
All of these alterations were burned to an EEPROM that I mounted in place of the original ROM in the machine.
Those were the days!
05-06-2017, 04:48 AM
I had a TK-85 the Brazilian "discrete" (no ULA) clone of the ZX-81. Mine had an extra EEPROM with fast loading and saving routines. I remember that I had discovered how to type more than one line with the same number by poking into the line number space. I had a lot of fun playing b/w games with almost no graphics and no sound...They were *fun* !
05-07-2017, 01:40 PM
Hello!
Actually I started programming with the Ti59 and a Commodore PET 2001 my school bought when I was in my last year. But the Sinclair ZX-81 was my first "home computer" too. No way could I afford a PET then, but the ZX-81 (which I bought as kit to save some money) and a second hand black-and-white TV were just doable. I tinkered around quite a bit with that, from memory extension, EPROM programmer, Centronics printer interface and most difficult of all: connecting a proper keyboard. Unfortunately nothing of that survived to this date. The Spectrum I skipped because I needed a proper computer with a decent keyboard and 80 characters per line on screen to write my masters thesis. The Spectrum was too much of a toy for that and it's successor, the QL, was too strange. So I got an Amstrad 464 (sold in Germany as "Schneider 464") instead. Apart from it's native BASIC it had CP/M and could run a decent word processor and spreadsheet - at least for the mid 1980ies.
(05-02-2017 09:54 AM)grsbanks Wrote: [ -> ]The ZX-81 is the machine that I cut my programming teeth on ...
Actually I started programming with the Ti59 and a Commodore PET 2001 my school bought when I was in my last year. But the Sinclair ZX-81 was my first "home computer" too. No way could I afford a PET then, but the ZX-81 (which I bought as kit to save some money) and a second hand black-and-white TV were just doable. I tinkered around quite a bit with that, from memory extension, EPROM programmer, Centronics printer interface and most difficult of all: connecting a proper keyboard. Unfortunately nothing of that survived to this date. The Spectrum I skipped because I needed a proper computer with a decent keyboard and 80 characters per line on screen to write my masters thesis. The Spectrum was too much of a toy for that and it's successor, the QL, was too strange. So I got an Amstrad 464 (sold in Germany as "Schneider 464") instead. Apart from it's native BASIC it had CP/M and could run a decent word processor and spreadsheet - at least for the mid 1980ies.