CP/M is really open-source now

https://retronic.us/cp-m-is-now-really-open-source/

by jstanley • 4 years ago

393 208 4 years ago

retronic.us

gjvc2• 4 years ago

Symbolics next, please!

Tomte• 4 years ago

Good luck hoping for that!

They sold their "first .com domain" to some guy who… seems to be a domain squatter (although he writes a lot about not being one).

Companies that eager to make a quick buck are usually not the ones open-sourcing their stuff.

rbanffy4• 4 years ago

It certainly feels like the people in the Amiga space. They'll milk their cow until its last drop of blood.

gjvc2• 4 years ago

this is the guy who presumably sold the original domain, http://www.symbolics-dks.com/

rbanffy4• 4 years ago

That'd be INSANELY cool.

Let's go a bit further then.

Next, open source SCOPE, NOS/VE and PLATO!

cestith2• 4 years ago

For nostalgia purposes, I'd like to see MUSIC & MUSIC/SP source with a fully open license. It was on our mainframe at uni in the 1990s.

skywal_l• 4 years ago

I remember, when I was a kid, having a CP/M diskette for the Amstrad CPC. It was provided with the machine. Every now and then I would try it out, not really understanding what it was about.

Years later I learned, reading about it, that it was some sort of "professional" OS on which productivity software would be used.

Does anyone actually used that OS on CPC or any other 8bits machine of the 80s to do anything remotely useful? Genuinely interested.

jstanley3• 4 years ago

I haven't used a real 80s computer (except in a museum). I've used CP/M a fair amount on an RC2014[0], but never for anything you might describe as "useful".

[0] https://rc2014.co.uk/

stevekemp2• 4 years ago

Same here, I've been running a single-board Z80-based system with 64k and CP/M 2.x

I worked my way through the various infocom adventures, and even wrote my own trivial text-based adventure game in Z80 assembly language - later porting it to the ZX Spectrum (which was the actual computer of my youth).

It's fun to play with these systems, and I've rebuilt the CP/M from sources a few times to add simple changes and new built-in commands.

taffronaut• 4 years ago

I worked on an industrial process monitoring system using CP/M in the 80s. It wasn't on CPC. It ran on a professional Z80-based S100 bus system with lots of I/O cards.

omega1• 4 years ago

I did, on a Czechoslovak 8080-based machine called TNS: I have written & cross-compiled a fulltext screen editor for another 8080 machine. It was written in the assembly language, and the resulting product had less than 2 KB.

PaulHoule• 4 years ago

CP/M was a lot like MS-DOS. People used the Wordstar word processor on it, you could run a BASIC interpreter and compiler on it. There was an upgraded version called ZCPR3 that was used on a BBS server in my town where you could log in and use the command line.

zekica• 4 years ago

Me too. I used it only for copying floppy disks. I didn't know better at the time.

Doctor_Fegg3• 4 years ago

Yeah, I used it a fair bit on the CPC.

There was huge amounts of CP/M software, much of it distributed for the CPC by "public domain libraries", who'd send you a disk of stuff by post for a small fee. (I ran one such!) But, to be frank, it was a minority taste because there were often faster, more graphical native programs available - i.e. running under the CPC's ROM-based firmware. For example, why would you use a CP/M wordprocessor when you could use Protext? Why would you use a CP/M assembler when you could use Maxam? And so on.

So CP/M programs on the CPC tended to flourish in areas where there wasn't much decent native software. Comms programs, for example - dialling up to a BBS, or even running one. (There were a couple of BBSs run on CPCs using the ROS software under CP/M.) Languages other than BASIC or assembler. Compression/archiving.

CP/M was a bigger thing on the Amstrad PCW because it didn't really have native firmware, and because the hardware was closer to a decent CP/M machine.

dividuum• 4 years ago

Same here. Had it on the CPC464. Had no idea what to do with it other than IIRC loading an image editor whose highlight (for me) was a brush in the form of a propeller fighter plane :)

boffinAudio2• 4 years ago

Wrote thousands and thousands of lines of code on CP/M, back in the day - not on an Amstrad CPC back then, rather some other strange machine - but it opened the door for a lot of great work in the decades that followed.

In my retro collection I currently have a CPC6128 that boots CP/M and for which I have Turbo C and Turbo Pascal installed.

I prefer to run SymbianOS on it though - it has multitasking, a network stack and a working GUI. ;)

lproven20• 4 years ago

Symbian OS is something entirely different: a native ARM OS written in C++ for smartphones.

You're probably thinking of SymbOS:

http://www.symbos.de/

shadowofneptune• 4 years ago

CP/M was at one point the native platform of Turbo Pascal. It only got fine-tuned for MS-DOS in later versions.

defined• 4 years ago

Yeah, I wrote quite a bit of Turbo Pascal code on CP/M on a Radio Shack TRS80 Model II. I loved TP and CP/M, especially TP.

lproven20• 4 years ago

Do you mean back then, or now?

wazoox• 4 years ago

There was a famous tracker for the CPC6128 that ran on CP/M. The name escapes me ATM.

marktangotango3• 4 years ago

There was a category of med/high range microprocessor machines ($10k+) that used it a lot, like Z-80 S100 machines with a bunch of "custom" expansion cards. I don't recall any of their names now, but if you look at the ads in late 70's Byte magazine you'll see them.

sedatk4• 4 years ago

Yes, I remember using Dr.Logo on CP/M on my friend’s CPC6128 and being very impressed with the capabilities of the language compared to BASIC. I also loved how detailed were the help text for the CLI tools. I remember reading HELP pages. I used to like command-line option syntax in brackets too. It felt very thorough and professional compared to AMSDOS :)

atq21192• 4 years ago

I remember using Wordstar and Turbo Pascal (version 3.0, I think?) via CP/M on a CPC.

billforsternz• 4 years ago

My first job straight out of engineering school in 1983 was developing Z80 embedded code. My 'development system' was some kind of semi home made floppy disk based CP/M computer with 48K of RAM and the native Dev tools including ED a command line editor and ASM an 8080 assembler (which was basically sufficient if not ideal for writing Z80 code). For the first few days I recall being confused about the difference between the ED command line and the CP/M command prompt. In other words, I was all at sea. But it was basically being thrown into the deep end and I learned fast. Within a year or so I was writing my own BIOS for an Intel bubble memory based customer CP/M computer that we were embedding into a field application. I didn't have the proper OEM documentation, but if you understood the CP/M architecture you didn't really need it.

linuxhansl• 4 years ago

My foray into disk-based operation systems. Oh, sooo many years ago. A friend of mine had it, and I would ride my bike through country roads as a kid to play around with it.

zabzonk5• 4 years ago

Lots of the source of CP/M came with the distribution, and it wasn't hard to dis-assemble specific bits you were interested in.

Some CP/M software (I'm thinking of WordStar specifically here, but no doubt others) almost required you to write a keyboard and display handler in Z80/8080 machine code to get decent performance over the generic CP/M code - been there on Research Machines 380Zs.

jstanley3• 4 years ago

Source has been available for years, it just hasn't been clear whether it was legal to redistribute it. Now it's clear :).

bornfreddy• 4 years ago

...clearer (if at all). The proper license, whatever it is, is still missing. Sorry. :)

doctor_eval2• 4 years ago

Why about MP/M. I loved having more than one user on a 8080.

dfawcus4• 4 years ago

Source and binaries are on the site:

http://www.cpm.z80.de/source.html

http://www.cpm.z80.de/binary.html#operating

Search for MP

doctor_eval2• 4 years ago

That is so cool. I'm not really a retro-computing guy and am unlikely to ever run this code, but it does bring back memories of bringing home an old unsold box from work, sitting on the garage floor, writing a program in unfamiliar 8080 mnemonics, and getting two terminals to chat to one another. OTOH it might be fun to get something working on a Z80 SOC. Or something like this https://hackaday.com/2017/01/02/retrocomputing-for-4-with-a-...

Has anyone ever trans-compiled Z80 assembly to a microcontroller? Is that even a thing?

kriro• 4 years ago

That is cool news because it's probably a nice starting point for osdev projects. At least more code to read :)

I feel like the code was available before and I read parts of it but I may remember it wrong.

Edit: Yes it was indeed "just" a license clarification. Link to the source: http://www.cpm.z80.de/source.html

usr1106• 4 years ago

In high school in 1980 we had Commodore PETs. They had no tangible OS, just a BASIC interpreter in ROM. There was an easter egg that made it say Microsoft or wasn't it spelled MicroSoft? Either way a company nobody had ever heard of.

CP/M had the aura of being something for real pros. Read some journal articles and it looked really complicated. But without suitable hardware I had never any chance to touch it.

In 1983 I went to university where beginner courses happened on VAX/VMS and my definition of "pro" got shifted.

hdjjhhvvhga2• 4 years ago

In high school in 1980 we had Commodore PETs. They had no tangible OS, just a BASIC interpreter in ROM.

Five years later the Commodore 128 appeared. It had the best of both worlds: could run all C64 games and CP/M. These were magic times.

mongol4• 4 years ago

I always booted mine while pressing the Commodore key. Waste of money.

salmo• 4 years ago

I inherited one of these from a friend in 2000. The ‘l’ key switch was broken. It (like most) were only booted into C64 mode and used for Batman and stuff. ‘L’ was broken because of ‘load’? I think that was the command. It’s been too long.

I passed it on, but wish I didn’t. At this point, I probably could have replaced the switch.

rasz3• 4 years ago

128 was a scam. It was a way for Commodore to get rid of unused sunk cost R&D (MOS 8563). Buyers were promised C64, but twice the number so must be 2x better, received C64 with another almost separate computer glued to its ass. Second graphic chip requiring expensive monitor, second CPU. As a bonus manufacturing C128D was more expensive than Amiga 500!

dhosek• 4 years ago

The early microcomputer OSes were little more than program loaders and only came into play if you had a disk drive. Even MS DOS was not much more than a program loader for most of its existence. It was a little jarring when making the transition from a TRS-80 or Apple ][ or Commodore computer to something running MS-DOS or CP/M that you could no longer just type 10 PRINT "HELLO, WORLD!" to start writing a program.

elvis70• 4 years ago

WAIT 6502,1 would output MICROSOFT! https://www.c64-wiki.com/wiki/Microsoft#Easter_Egg_.28Micros...

pavlov2• 4 years ago

CP/M was the popular operating system that IBM wanted to license for their skunkworks Personal Computer project. But the founder of Digital Research, the company that developed CP/M, was more interested that day in going flying his plane than meeting with corporate men in navy suits. (This may be apocryphal.)

IBM turned instead to their second choice, a small company that was supplying BASIC interpreters to many 8-bit micros. The company didn’t actually have a suitable disk operating system product, but the founder knew someone who did. He made a deal to license the source code for a fixed fee and no limitations on redistribution. And that’s how Bill Gates acquired MS-DOS for $50k.

Neil442• 4 years ago

CP/M was nice, it's a shame we got saddled with MS-DOS for decades.

pjmlp4• 4 years ago

Having started my MS-DOS path with version 3.3, and used all MS-DOS versions, also the DR-DOS 5.0 and 6.0 versions, experienced CP/M on the Spectrum +3A, I fail to see how CP/M was better.

jll292• 4 years ago

IBM turned instead to their second choice, a small company that was supplying BASIC interpreters to many 8-bit micros.

a small company founded by a kid, Bill Gates, whose parents happened to be IBM's lawyers.

de6u99er• 4 years ago

A small but probably important detail!

throwaway9870• 4 years ago

I have never heard that before. Do you have a reference? What I have read is that Bill Gates's mother was on board of directors of United Way with the chairman of IBM.

dtech• 4 years ago

And had access to a computer at school starting eight grade in 1968, at a time purchasing price started at $500k, 4 million adjusted for inflation.

P_I_Staker• 4 years ago

but what kind of lawyers were they?

monocasa• 4 years ago

The real story was that she was a board member on another corporate board with someone who was also on IBM's board. Even with that indirection, she did use that influence to convince IBM to use Microsoft for the PC.

https://www.nytimes.com/1994/06/11/obituaries/mary-gates-64-...

pjmlp4• 4 years ago

Small correction, he acquired QDOS, which was then morphed into MS-DOS.

lproven20• 4 years ago

Initially, just licensed. Only later acquired.

If you're going to correct, you've got to be right!

I say this as something of an HN admirer of yours, because you so often comment to people with exactly what I would say myself. We should talk.

AlbertoGP2• 4 years ago

was more interested that day in going flying his plane than meeting with corporate men in navy suits. (This may be apocryphal.)

That day was his wife’s birthday and he had already promised her to go flying.

Here it is reported by Stewart Cheifet, his long term co-host of the Computer Chronicles (which is a treasure and freely available in the Internet Archive https://archive.org/details/computerchronicles):

“... but it’s just as good. It’s just that that day they came was his wife’s birthday, and he said «Sorry, I’m committed to my wife, we’re gonna go flying» [...] He didn’t have to worry about money, but what killed Gary was just the... he was annoyed at what happened. [...] [Cheifet in an excerpt from Computer Chronicles in 1983:] Gary, are we at the end of the line in the evolution of computer hardware?” https://www.youtube.com/watch?v=WdtHS_X1ibg&t=430s

Edit to add: the first video in the Computer Chronicles Archive collection is the “Gary Kildall Special” from 1995, and I quote here a couple of paragraphs:

“In 1976, Gary and his wife Dorothy founded a company called «Intergalactic Digital Research», later shortened to «Digital Research».”
“The main thing that CP/M brought that was different from how anybody else was approaching micro-computers, was that Gary made a logical separation of the physical I/O system from what was called the BDOS. The physical layer system was called the BIOS, the Basic I/O System, and that was the term that Gary used in early CP/M. The BDOS was the Basic Disk Operating System. The BDOS was independent of the specific hardware that you had in your micro-computer. By comparison, we are looking at the time of UNIX being out as a major mini-computer operating system, and you could not move executables of any application program from one UNIX machine, unless it was an identical machine, to another system. So that was really a remarkable innovation.”
“CP/M sold extremely well, and DRI flourished. The company expanded to larger quarters across the street, the number of employees grew from 9 to 24. When the new VAX mini-computer arrived, it was too large to fit inside the building, so the entire structure was lifted off its foundation to accommodate the machine. A beaming Gary told the staff that they would all be getting a «raise» that week.”

dfxm12• 4 years ago

I've got to second checking out Computer Chronicles for anyone at all interested in the history of computers or people just looking for a little nostalgia.

The YouTube algorithm suggested it to me a few months back and I've been watching episodes whenever I get a little downtime. Watching John Dvorak teardown a brand new IBM PS/2 literally and figuratively was pretty fun.

AlbertoGP2• 4 years ago

Reply to myself: watching that Gary Kildall Special of The Computer Chronicles, there is a segment at 17:10 talking about that incident, presented too by Stewart Cheifet, where Tom Rolander, first DRI employee, tells that he was flying with Kildall that morning for a business trip, then “flew back down and joined the IBM meeting, we were there for the meeting later in the afternoon”.

A sibling comment (https://news.ycombinator.com/item?id=32082362) tells a story consistent with this one.

The first video from which I quoted Cheifet is from 2013, while this last one is from 1995. I have no way of verifying which one is right.

Here is Tom Rolander again, in 2017, in an interview with the Computer History Museum, describing the background between Gary Kildall, Bill Gates, and IBM, and then a very detailed report of the incident, again consistent with his 1995 report: “Oral History of Tom Rolander” https://www.youtube.com/watch?v=VREZ6Zx_usc&t=5040s

forinti• 4 years ago

Surely the choice of OS cannot depend on a single day.

CP/M seemed much nicer.

Narishma• 4 years ago

How was it nicer?

guenthert2• 4 years ago

Hell no. (MS-)DOS was awful in every aspect, but CP/M was worse. It's quite amazing how age seems to make people paint the distant past rosy.

In 1980 CP/M would have been the obvious choice though for a micro computer, due to market dominance (there were penty of commercial software application available for CP/M, including, later, WordPerfect and Multiplan) and limitation of the hardware at that time. Glad that we moved on.

seemaze• 4 years ago

Entertainingly clarified in the wonderful podcast 'Advent of Computing' ep. 36 [0]. Highly recommended!

[0]https://adventofcomputing.libsyn.com/episode-36-the-rise-of-...

lproven20• 4 years ago

Yes it's apocryphal. Please stop repeating it. It's disrespectful to the late great Dr Gary Kildall, for a start, and to his cofounder and business partner, the late Dorothy McEwen.

From memory and without consulting much in the way of references:

* Dr Kildall's personal and business partner Dorothy was the company's cofounder and dealt with contracts etc. https://en.wikipedia.org/wiki/Dorothy_McEwen_Kildall

* Dr Kildall, as the CEO of the most significant microcomputer OS vendor in the world at that time, had his own plane, yes, and he piloted it himself. He was going on a site visit to a major customer. It wasn't for fun; it was a business trip, and it wasn't his job to deal with IBM.

* DR had good reasons to refuse the deal.

1. IBM wanted DR to sign a very restrictive NDA; DR had a policy against that. Ms Kidlall refused. MS, as a small company with nothing much to lose, happily signed.

2. IBM offered $250K for an unlimited license. DR quite rightly refused and so did MS. MS retained the rights to licence DOS to other vendors, and it did, a lot, and made a lot of money thereby. The deal IBM offered DR precluded that.

* AIUI, MS licensed SCP QDOS for $50K. It only bought it in later on, for a lot more money. It ended up paying $1M for it, and that was still a bargain.

This is not ancient history. It was only about 40 years ago. Many of the protagonists are still alive and active, notably Tim Paterson and a certain William H Gates the 3rd.

hindsightbias• 4 years ago

So DR had a dumb policy and were not great negotiators. Gates knew exactly what had fallen into his lap.

jecel• 4 years ago

The IBM guys had gone to Seattle expecting to license CP/M. Their "benchmark" (in business terms) was the Apple II with Microsoft's Z80 SoftCard running CP/M. As far as they could tell, Microsoft owned CP/M. Bill Gates told them otherwise, phoned Gary Kildall but had to be vague and then sent the IBM guys on a plane to California. I can only guess they were pretty upset even before they ever got to DRI.

People's memories of what happened vary. One of the IBM guys claimed no meeting happened and they went back to Seattle even more upset (which is the most popular version). Gary claims that after some back and forth between Dorothy and her lawyer she did sign the NDA and that he arrived towards the end of the meeting and had a nice chat about the technical side with the IBM people.

The PC was launched with a choice of three operating systems: PC-DOS (the licensed MS-DOS), CP/M86 and UCSD Pascal. But the first cost less than a third of the other two.

II2II2• 4 years ago

We will never know what happened on that day. None of the witnesses can be considered reliable. Even if they consider their own accounts as honest, the eventual fallout would taint their memories of the events. The best we can hope for is documentation to support one hypothesis or another (e.g. contracts).

That said, I do agree the common account is both disrespectful and inaccurate. I never understood why people would believe that Gary Kildall or Dorthy McEwen would brush off a business meeting. They may not have been an empire builders, but they were successful business people who built a successful business.

kmeisthax• 4 years ago

There's a third reason why the DR/IBM deal didn't work out: CP-M/86 was extremely delayed. The reason why SCP QDOS even existed was that SCP had an S-100 machine with an 8086 in it and there was no OS that could run it.

Microsoft wasn't necessarily a "small company with nothing to lose", either. They had the best BASIC interpreter in the business[0] and everyone licensed from them already.

[0] This also allowed them to strong-arm Apple into making a few licensing deals that would kill all the "look and feel" shenanigans later into that decade.

kabdib2• 4 years ago

I did some work at DRI in 1984 (my group was housed in the old KMST television studio, on the outskirts of the DRI campus, for about four months while we ported GEM to the Atari ST).

My manager talked with Gary about the CP/M incident at one point. Apparently some "guys in suits" showed up without an appointment one day, wouldn't say who they were, wouldn't sign an NDA, and were demanding to see Gary. They were sent away without talking to anyone. Gary was in his office the whole time, and definitely not flying.

Take it as you like. My Kildall Number is 2.

anonymousiam• 4 years ago

You left out the part about SCP blatantly ripping off the CP/M OS to produce QDOS, which Bill Gates purchased in order to license to IBM. The CP/M source code was widely available, but still copyrighted by DRC. At the time, I recall having a CP/M-based x86 cross-assembler that did a pretty good job. It probably took Tim Paterson a day or two to hack QDOS together given the availability of the CP/M source code and tools. If QDOS was an original work, why use "5" as the system call interrupt? (CP/M used "call 5".) The QDOS system call function list and arguments are identical to CP/M. The FCB-based disk layout was also virtually the same as CP/M.

https://en.wikipedia.org/wiki/Seattle_Computer_Products

https://www.theregister.com/2007/07/30/msdos_paternity_suit_...

phendrenad22• 4 years ago

When I heard the (fake) story, it went like this:

IBM offered to buy DOS first, but Gates & Allen rejected it. Gates, being an acquaintance of Gary Kildall, told them to give Digital Research a try. He phoned Gary and said, playfully "They're coming for you next". Gary took this to mean someone was coming for him, and jumped in his plane and left. When IBM showed up, he was mysteriously missing, and everyone involved was confused.

Usually truth is stranger than fiction, but in this case I think the fiction above is hilarious and top-notch alternate history.

piokoch• 4 years ago

"This may be apocryphal."

Yes, you story is not true at all. Bill's mom was higher-up executive in IBM and persuaded company to do business with her son's company, not DR. That gave rise to Microsoft.

BTW: for a long time many people were using DR DOS as a much better replacement for MS DOS, which was broken in many places (I did that too). Bill was not very much worried about shipping broken stuff, that's why we have seen "great" stuff like Windows ME or Windows Vista. Sadly, at that point Microsoft was practically a monopoly on the operating system market (Unix/Linux were not a thing, Apple was fighting with its own problems).

The good thing that happen to Microsoft and to its users was Windows NT kernel, that was a sort of a rip-off of rather sane VMS kernel, so Windows NT, Windows 2000 and their successors were more or less acceptable operating systems.

mbrubeck• 4 years ago

Bill's mom was higher-up executive in IBM

This is also not true at all! Mary Gates never worked for IBM. However, she knew IBM's chairman John Opel.

dboreham2• 4 years ago

That gave rise to Microsoft

Microsoft was already one of the biggest most significant microcomputer software companies.

jodrellblank• 4 years ago

"Bill was not very much worried about shipping broken stuff"

This goes against claims like[1] where Bill Gates got the spec for Excel Basic (to become Visual Basic for Applications) and read it and annotated it overnight, to grill the the author on the details, and says "Bill Gates was amazingly technical. He understood Variants, and COM objects, and IDispatch and why Automation is different than vtables and why this might lead to dual interfaces. He worried about date functions. He didn’t meddle in software if he trusted the people who were working on it, but you couldn’t bullshit him for a minute because he was a programmer." and

"Over the years, Microsoft got big, Bill got overextended, and some shady ethical decisions made it necessary to devote way too much management attention to fighting the US government. Steve took over the CEO role on the theory that this would allow Bill to spend more time doing what he does best, running the software development organization, but that didn’t seem to fix endemic problems caused by those 11 layers of management, a culture of perpetual, permanent meetings, a stubborn insistance on creating every possible product no matter what, [...] and a couple of decades of sloppy, rapid hiring"

[1] https://www.joelonsoftware.com/2006/06/16/my-first-billg-rev...

JJMcJ4• 4 years ago

You could get a CP/M-86 license for the PC. Also Turbo Pascal. But MS-DOS was the cheapest so it prevailed.

One of the most impressive things about this is that Bill Gates and MSFT actually had a deal with IBM and came out ahead. Very few companies did this.

lproven20• 4 years ago

It was not Turbo Pascal. You are confusing it with the UCSD p-System, a different Pascal.

https://en.wikipedia.org/wiki/UCSD_Pascal#UCSD_Pascal_and_th...

TP was a Borland app which ran on CP/M and later DOS; it would be no use on its own. It was not an OS.

The 3 OS choices for the IBM PC were:

[1] The UCSD p-System, a Pascal environment with a VM for portable code.

[2] PC DOS, IBM's version of MS-DOS.

[3] DR CP/M-86, at about 3× the price.

drieddust• 4 years ago

Bill Gates mother having a seat on IBM's board was not a factor in IBM giving him such a sweet deal?

themadturk4• 4 years ago

Mary Gates was on the board of United Way; so was IBM's chairman at the time, so they were friendly. She didn't work for as a director of IBM.

timonoko• 4 years ago

I thought I had CP/M source code for Osborne-1. But no, I have only inch-thick listing of BIOS. And it did not matter, one always used direct Bios-calls for speed.

CP/M was not actually needed for this implementation, it could boot on its own: http://timonoko.github.io/Nokolisp.htm

lkxijlewlf• 4 years ago

Slightly off topic:

I recall as a youngin watching Gary Kildall on the Computer Chronicles. I was always fascinated by what people were doing with computers. I know it is nostalgia and there's infinitely more to learn about today than there was then, but I do miss that era of computing.

Cockbrand2• 4 years ago

Of course, there's a CP/M emulator in the browser now, so you don't have to dig out your Z80/8080 computer: https://www.tramm.li/i8080/

jhallenworld• 4 years ago

HP should open OS/8 and RT-11, the two big influences on CP/M. OS/8 is kind of remarkable, running on a system arguably less powerful than the first 8-bit home computers (I would say they are closer to PIC microcontrollers, but with more RAM):

https://www.pdp8online.com/os/os8/index.shtml

PDP-8 memory is heavily paged. There are 128 word pages- direct addresses can only reach within the current page, and literals (immediate data including addresses to other pages) have to be allocated out of this current page along with the instructions. Second, there are 4K-word fields. So you need to use far jumps and returns to access outside the current field. This is just like PIC microcontroller pages.

OS/8 reserved only two pages for itself. Things like the command interpreter were swapped out to disk or DECTape.

https://en.wikipedia.org/wiki/DECtape

If the application needed device drivers, it got to choose which pages the drivers would occupy- meaning the device drivers had to be written as position independent code. Also I think each driver was limited to two pages..

Barrera• 4 years ago

The discussion is not over yet, but we believe this statement is equivalent to the well-known BSD or MIT licenses.

That's not now I'd interpret it. "Open Source" in my mind means that the software uses one of the OSI approved licenses. The quoted paragraph:

Let this paragraph represent a right to use, distribute, modify, enhance, and otherwise make available in a nonexclusive manner CP/M and its derivatives. This right comes from the company, DRDOS, Inc.'s purchase of Digital Research, the company and all assets, dating back to the mid-1990’s. DRDOS, Inc. and I, Bryan Sparks, President of DRDOS, Inc. as its representative, is the owner of CP/M and the successor in interest of Digital Research assets.

is not even a license in the traditional sense. It defines nothing. Whatever rights it grants do not appear to be transferrable. Worst of all, it does not even mention source code.

If the owners of the CP/M source code want to make it open source, what's so hard about attaching the actual MIT or BSD licenses to a source distribution and publishing it?

nibbleshifter• 4 years ago

what's so hard about attaching the actual MIT or BSD licenses to a source distribution and publishing it?

From experience in related things: lawyers.

zozbot234• 4 years ago

This is most likely why the post mentions that "discussion is not over yet". They seem to be quite optimistic that we might be getting a proper FLOSS release.

Cyberdog• 4 years ago

This sort of confusion could have been avoided if they had just said "the source code to this program is now free to distribute under the (MIT|BSD|GPL|etc) license" from the beginning. Nobody knew what exactly the intent of this novel "let this paragraph represent" approach was supposed to be, and now it just sounds like we have a slightly clearer idea.

No need to get cutesy with something as important as your license terms, people.

Communitivity• 4 years ago

I remember CP/M with fondness. My father gave me an Osborne 1 for my first computer when I was 12 (41 years ago). It came with CBASIC2 as well as MBasic, and I managed to find a Lisp (I forget what flavor). To put the Osborne 1 in perspective, the stats:

* 64kb memory (yes that's kilobytes)

* 2 5 1/4 floppy disks

* No hard disk

* 5" monochrome green screen monitor

* 4 MHz CPU

* 37 watt power supply

* weighed ~25 pounds

jfengel• 4 years ago

Plus an RS-232 for your modem and an IEEE 488 for your printer.

That CPU lacked a multiply instruction, so you had to implement that yourself.

veltas• 4 years ago

The multiply instructions on later CPUs were implemented as microcode programs on the silicon, so sometimes it was faster to write your own or a specialised routine anyway.

jahnu• 4 years ago

Luxury!

https://m.youtube.com/watch?v=ue7wM0QC5LE

;)

OnlyMortal2• 4 years ago

4mhz CPU?

Luxury super computer!

varjag• 4 years ago

3.5-4Mhz was standard for most Z80 based systems.

cosmiccatnap• 4 years ago

I'm sorry but it's not on MIT, GNU, or BSD so I would go so far as to say the title is clickbait...like can I take this code and try and get it to work on my x86 machine and then commit my changes under bsd? Probably not

Can someone point me to a repo to look at it? I can't find a link and it doesn't show up on Google.

dboreham2• 4 years ago

https://github.com/brouhaha/cpm22/blob/master/bdos.asm

from http://www.cpm.z80.de/source.html

kazinator• 4 years ago

This right comes from the company, DRDOS, Inc.'s purchase of Digital Research, the company and all assets, dating back to the mid-1990’s

What the Wikipedia says, if you piece it together is that Bryan Sparks founded Caldera in the mid 1990's, which bought Digital Research. Around the time Caldera went defunct in 2002, Sparks started DeviceLogics which got renamed to DRDOS Inc. So that must have inherited the Caldera assets, including the Digital Research stuff.

smm11• 4 years ago

So IBM went crazy with CP/M, and Microsoft suffered. We'd now have CP/M 11, and DOS would be open-source now.

sbuk• 4 years ago

In all likelihood in that timeline DOS as we know it wouldn't have existed.

BirAdam• 4 years ago

I am not so certain that it would have made much difference. Microsoft would still have produced both BASIC and Windows, and we may have had the exact same evolution anyway. DigitalResearch's GEM was mired in legal red tape preventing from much evolution.

Also, MSDOS is opensource now.

https://computerhistory.org/blog/microsoft-ms-dos-early-sour...

phendrenad22• 4 years ago

Always excellent when a piece of computing history has it's source made available. Even better when it's provided under a libre license, as this is!

CP/M is a powerful example of what you can do without multitasking. The code is also a time capsule of development techniques and styles of the time.

marcodiego• 4 years ago

Good but 30-40 years too late.

CP/M is really open-source now

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