ZX81 floppy disk systems
Posted: Sun Sep 18, 2022 12:30 am
Recently reading the "10 Year Sinclair Retrospective" piqued my interest in floppy disc systems for the ZX81. And it occurred to me that I knew virtually nothing about them. Here's a summary of the rabbit hole i've gone down
When the ZX81 came out in 1981, home computers used tape recorders to save and load programs. Of course a floppy disk is more convenient:
* more reliable/consistent
* faster in loading
* Faster in finding a particular program (no fast-forwarding/rewinding needed)
* better organizing & storing. Multiple programs stored on a diskette can be shown using the DIRECTORY command, and can be loaded on demand
photo: George Chernilevsky, Public domain, via Wikimedia Commons
In 1981, the 5.25 inch floppy disk was the choice of hobbyists -- the smaller 3.5 "hard-case" floppy had not been introduced yet. With the rise of CP/M, floppy drive prices were dropping (e.g. a raw drive was $399 in 1979, down to $179 in 1982 and $79 in 1986) And with the recent introduction of the IBM PC, the 5.25" disk drive and media would soon become even more affordable
In 1982, the first floppy disk system for the ZX81 appeared
November 1982 seems to be the first ad for the Aerco controller.
Floppy Disc Interface $179
5.25" double density floppy disc drive $189
Power and cable for two drives $69
That's a total of $437 for a single-floppy setup. In 2022 dollars it would be $1,346
In 1982 I was in my last year of high school, in the Computer class we had a TRS-80 with floppy disk drive (I still have a couple of disks from it). I don't know what the class was officially titled, it wasn't really a computer literacy class, and there was no fixed curriculum. It was the first year at our school for such a class. The mathematics teacher was assigned the class and he just let us do whatever. The only requirement was to complete a "project", which was self-selected. I chose to write a music playback program in machine code. It played twinkle twinkle little star, and could be heard over an AM radio. The teacher said he didn't understand how it worked, and gave me a passing grade for the class. But mostly we tried out the BASIC examples from the manual, played games (especially Scott Adams adventures) and hacked about. For example, we changed the bootloader on floppy disks to display custom messages. Of all the students in the class only one other guy besides me showed this much interest. Later we both ended up working at Microsoft. The little 8-bit machines started many people down a path in the industry
This other student got an Apple II with floppy drives. The cost was more than a year's home rental for me. So with that background, I never even considered get a floppy drive setup for the ZX81
And it seems that many felt the same. It's been said that while USA home computer enthusiasts favored floppy disks, Europeans favored tapes
ZX81 ALTERNATIVES to Floppy Disks
* tape recorder: cheap, ubiquitous but slow
* digital tape player: TZXDuino/MaxDuino/CASDuino/SVI-CAS
* SD-card system: ZXpand+ multi-purpose interface
* USB stick system: Vdrive
* Floppy Stringy: CAI/ESF Stringy Floppy by Extatron/A&J
* Hard drive: IDE controller (pre-SATA technology) see IdeDos
* Online fileserver: ZX-WESPI
FDC setups for ZX81
* Aerco FD-ZX a.k.a. "Aerco 1000 Disc System"
* Larken "ZX81 Disk System" and LDOS
* Mageco Electronic "Interface floppy ZX81"
* Macronics "F.I.Z. Floppy Disk Interface"/Compusa "Floppy Disk Controller"
* Compusa "FDC-100 Floppy Disk System"
* Analogue Interface Systems
* Audio Vision "Floppy Disc Controller"
* Sinclair Place "Floppy Disk Interace"
And the new one:
* ZX1541 interface to use Commodore 1541 disk drive with ZX81
When the ZX81 came out in 1981, home computers used tape recorders to save and load programs. Of course a floppy disk is more convenient:
* more reliable/consistent
* faster in loading
* Faster in finding a particular program (no fast-forwarding/rewinding needed)
* better organizing & storing. Multiple programs stored on a diskette can be shown using the DIRECTORY command, and can be loaded on demand
photo: George Chernilevsky, Public domain, via Wikimedia Commons
In 1981, the 5.25 inch floppy disk was the choice of hobbyists -- the smaller 3.5 "hard-case" floppy had not been introduced yet. With the rise of CP/M, floppy drive prices were dropping (e.g. a raw drive was $399 in 1979, down to $179 in 1982 and $79 in 1986) And with the recent introduction of the IBM PC, the 5.25" disk drive and media would soon become even more affordable
In 1982, the first floppy disk system for the ZX81 appeared
November 1982 seems to be the first ad for the Aerco controller.
Floppy Disc Interface $179
5.25" double density floppy disc drive $189
Power and cable for two drives $69
That's a total of $437 for a single-floppy setup. In 2022 dollars it would be $1,346
In 1982 I was in my last year of high school, in the Computer class we had a TRS-80 with floppy disk drive (I still have a couple of disks from it). I don't know what the class was officially titled, it wasn't really a computer literacy class, and there was no fixed curriculum. It was the first year at our school for such a class. The mathematics teacher was assigned the class and he just let us do whatever. The only requirement was to complete a "project", which was self-selected. I chose to write a music playback program in machine code. It played twinkle twinkle little star, and could be heard over an AM radio. The teacher said he didn't understand how it worked, and gave me a passing grade for the class. But mostly we tried out the BASIC examples from the manual, played games (especially Scott Adams adventures) and hacked about. For example, we changed the bootloader on floppy disks to display custom messages. Of all the students in the class only one other guy besides me showed this much interest. Later we both ended up working at Microsoft. The little 8-bit machines started many people down a path in the industry
This other student got an Apple II with floppy drives. The cost was more than a year's home rental for me. So with that background, I never even considered get a floppy drive setup for the ZX81
And it seems that many felt the same. It's been said that while USA home computer enthusiasts favored floppy disks, Europeans favored tapes
ZX81 ALTERNATIVES to Floppy Disks
* tape recorder: cheap, ubiquitous but slow
* digital tape player: TZXDuino/MaxDuino/CASDuino/SVI-CAS
* SD-card system: ZXpand+ multi-purpose interface
* USB stick system: Vdrive
* Floppy Stringy: CAI/ESF Stringy Floppy by Extatron/A&J
* Hard drive: IDE controller (pre-SATA technology) see IdeDos
* Online fileserver: ZX-WESPI
FDC setups for ZX81
* Aerco FD-ZX a.k.a. "Aerco 1000 Disc System"
* Larken "ZX81 Disk System" and LDOS
* Mageco Electronic "Interface floppy ZX81"
* Macronics "F.I.Z. Floppy Disk Interface"/Compusa "Floppy Disk Controller"
* Compusa "FDC-100 Floppy Disk System"
* Analogue Interface Systems
* Audio Vision "Floppy Disc Controller"
* Sinclair Place "Floppy Disk Interace"
And the new one:
* ZX1541 interface to use Commodore 1541 disk drive with ZX81