9 ms·

Games for IBM AS/400

96 points by theletterf 5y ago

Jondar 5y ago
I worked for a company that had Tetris and an analog clock app installed on their AS/400
markus_zhang 5y ago
Considering the power of mainframes, I wonder why there are few games made.
- kej 5y ago
  I would imagine there's a lot of overlap between places that use mainframes and places where anything unauthorized, let alone games, will get you fired.
  - 123pie123 5y ago
    many moons ago, I was lucky enough to have root (QSECOFR) access and treat the box as my personal play thing - even while running prod stuff. we could have put games on it, if we trusted the developer - well may be just the dev server. Windows NT 4 and Windows 3.11 was more interesting at the time with AOL dial up access
  - markus_zhang 5y ago
    Agreed, that's my thought too.
  - ASalazarMX 5y ago
    Definitely any company that could afford a (then) AS/400 wouldn't look kindly on using it for gaming. That being said, some did, otherwise these little games wouldn't exist. At one of my previous jobs, the end of the year was boring, no clients and projects would be on hold until January. One of those years I wasted a week making a crude reversi game complete with CPU player, and it was well received among the other programmers. We tried to make a checkers game, but turns out a checkers CPU player is a lot harder than reversi for business programmers.
    - markus_zhang 5y ago
      Is it possible to make a gui game?
      - ASalazarMX 5y ago
        AFAIK it can only do text games, but I don't know what improvements IBM has made in two decades. The other limitation is that the terminal buffers input until you press Enter, then sends the entire screen, so only turn-based games are practical. The buffering is a neat feature. Your AS/400 could be extremely busy (sometimes the operator would prioritize a very urgent process), but you could do a screenful of code, then press Enter and go for a coffee.
        reaperducer 5y ago
        This is why graybeards understand the difference between the [RETURN] key and the [ENTER] key. Accountants, too.
        jaak 5y ago
        I believe the AS/400 calls it Field Exit. One of the things I used to do for new users was remap Field Exist to Enter in the IBM 5250 emulation software. Then the enter key acted like the user expected (on a real 5250 terminal there is a separate physical Enter key located where the right control key is on modern keyboards). Explaining Field Exit vs Enter was something most users didn't get. However, they did understand Enter as like a submit button (like on web pages) and were fine selecting fields with the mouse.
        ASalazarMX 5y ago
        It's been many years, but wasn't that a key that allowed you to change input fields, just like TAB does it with web pages? IIRC that key was managed purely client-side.
      - _-david-_ 5y ago
  - markphip 5y ago
    You would be surprised. I worked for an AS/400 ISV and while the customers were all huge companies, the part of the company that ran an AS/400 was usually very small and had a lot of autonomy.
- racingmars 5y ago
  To be nitpicky -- The AS/400 is not a mainframe, it's what IBM calls a "midrange system" positioned between commodity x86 servers and mainframes. Today, the AS/400 OS (OS/400, or as it's known now, IBM i) runs on IBM's POWER servers. For a typical IBM i system you're talking a couple 10s of thousands of dollars, for a typical mainframe you're in the hundreds of thousands. Also regarding the power of mainframes: in the case of AS/400, it's definitely not what I would call fast. Everything runs on what is essentially a virtualization layer... the AS/400 instruction set (MI, or "machine interface") doesn't exist in any hardware, it's just run on top of a translation layer on top of (these days) POWER. It's a very weird system from top to bottom. As for actual mainframes, traditionally the power came not from raw CPU power, but from an architecture that efficiently handles parallel I/O. Definitely powerful for batch processing of large amounts of data, but not necessarily optimized for something like games.
  - Yuioup 5y ago
    Is AS/400 Open Source?
    - skissane 5y ago
      No, it is a closed source IBM product. I've seen copies of its installation media on "warez"/"abandonware" sites before, but there is no emulator for it so you can't run it unless you have real hardware. IBM has recently got quite keen on porting open source software to its Unix compatibility environment (PASE) – it is a way for IBM to make it feel fresher and more modern and more accessible to mainstream developers, for only a modest investment of resources. Even if you download the installation media from one of those sites, you can't run it because there is no emulator for it. Now, it is POWER, so in principle there could be an emulator, but QEMU only supports running Linux and AIX, not IBM i. Probably if someone wanted to, they could enhance QEMU to support running IBM i, but it would be a lot of work – IBM i exploits various obscure features, not just of the CPU, but also of the firmware, which AIX doesn't, and so understandably QEMU/etc don't implement those obscure features. Commercial emulators don't really exist either, because if you start selling a commercial emulator, it is almost guaranteed IBM will sue you. I think an emulator for the classic CISC hardware would be really cool – probably make the most sense to start by emulating System/38, then try to extend it to CISC AS/400. Who would ever carry out such a gargantuan and pointless task? Probably some day, eventually, someone will do it. And it will be cool. There were commercial third party emulators, of sorts, for the System/38, such as California Software Products' Baby/38 package. However, Baby/38 wasn't full system emulation, it was actually just an RPG compiler which supported the System/38 dialect, and had a limited emulation of OS services which RPG programs commonly used. They later followed up with a successor, Baby/400. I'm sure it was quite useful to people back in its heyday of the 1990s, trying to port their RPG business applications to Windows. Practical, but not very interesting from a technology perspective.
- jacquesm 5y ago
  Because they cost a ton of money to own and operate, and because they typically lacked graphical output, either in real time or at all. But that didn't stop programmers from writing games for them, those just didn't enter distribution, they were typically just run locally.
- Lutzb 5y ago
  I remember IBM mainframes being used as a backend for the MMO Taikodom by Hoplon entertainment. https://en.m.wikipedia.org/wiki/Taikodom https://en.m.wikipedia.org/wiki/Taikodom
icedchai 5y ago
Back in the 80's and early 90's, my uncle's company had an IBM System/36, which was a predecessor to the AS/400. They used it for accounting. The thing was a monster, and it looked exactly like the top photo on wikipedia: https://en.wikipedia.org/wiki/IBM_System/36 https://en.wikipedia.org/wiki/IBM_System/36 It had 8 terminals attached, and a couple of huge line printers. We opened up the main system cabinet one day, and the hard drive (about 200 megs?) was over a foot wide. The system also used "disk cartridges" which were several 8 inch floppies in a box. Supposedly the system cost almost $200K (in 80's money.) In the mid 90's they replaced it with PCs.
- jacquesm 5y ago
  As drive packs come those were pretty compact already. Prior to that a 200 meg pack + drive would be the size of a top loading washing machine. Packs were removable, you'd screw them into place with a handle at the top and after closing the lid they'd spin up. Massive gear, a pack of 11 platters weighed a couple of kilos and would spin up to several K rpm, and woe to you if the pack was written on a drive with a different alignment, then you'd have to get the heads re-aligned. This was one of the reason why most machine to machine data transfer was done using tapes. Slower, but more reliable and much, much cheaper. Packs would usually stay within the same datacenter, and likely would be assigned to the same drive though theoretically there was no reason why they couldn't be moved to a different one that had been calibrated with the same calibration setup.
- teh_klev 5y ago
  Back in the 90's I worked as a field engineer and had a few of these on contract. They're really nice machines to work on and a common task was replacing these hard disks when they failed. The IBM field service manuals were pretty good and you could repair/replace pretty much anything on-site. They look like monsters but they're actually really friendly to field service techs.

96 points by theletterf 5y ago

Jondar 5y ago

I worked for a company that had Tetris and an analog clock app installed on their AS/400

markus_zhang 5y ago

Considering the power of mainframes, I wonder why there are few games made.

kej 5y ago
I would imagine there's a lot of overlap between places that use mainframes and places where anything unauthorized, let alone games, will get you fired.
- 123pie123 5y ago
  many moons ago, I was lucky enough to have root (QSECOFR) access and treat the box as my personal play thing - even while running prod stuff. we could have put games on it, if we trusted the developer - well may be just the dev server. Windows NT 4 and Windows 3.11 was more interesting at the time with AOL dial up access
- markus_zhang 5y ago
  Agreed, that's my thought too.
- ASalazarMX 5y ago
  Definitely any company that could afford a (then) AS/400 wouldn't look kindly on using it for gaming. That being said, some did, otherwise these little games wouldn't exist. At one of my previous jobs, the end of the year was boring, no clients and projects would be on hold until January. One of those years I wasted a week making a crude reversi game complete with CPU player, and it was well received among the other programmers. We tried to make a checkers game, but turns out a checkers CPU player is a lot harder than reversi for business programmers.
  - markus_zhang 5y ago
    Is it possible to make a gui game?
    - ASalazarMX 5y ago
      AFAIK it can only do text games, but I don't know what improvements IBM has made in two decades. The other limitation is that the terminal buffers input until you press Enter, then sends the entire screen, so only turn-based games are practical. The buffering is a neat feature. Your AS/400 could be extremely busy (sometimes the operator would prioritize a very urgent process), but you could do a screenful of code, then press Enter and go for a coffee.
      - reaperducer 5y ago
        This is why graybeards understand the difference between the [RETURN] key and the [ENTER] key. Accountants, too.
        jaak 5y ago
        I believe the AS/400 calls it Field Exit. One of the things I used to do for new users was remap Field Exist to Enter in the IBM 5250 emulation software. Then the enter key acted like the user expected (on a real 5250 terminal there is a separate physical Enter key located where the right control key is on modern keyboards). Explaining Field Exit vs Enter was something most users didn't get. However, they did understand Enter as like a submit button (like on web pages) and were fine selecting fields with the mouse.
        ASalazarMX 5y ago
        It's been many years, but wasn't that a key that allowed you to change input fields, just like TAB does it with web pages? IIRC that key was managed purely client-side.
    - _-david-_ 5y ago
- markphip 5y ago
  You would be surprised. I worked for an AS/400 ISV and while the customers were all huge companies, the part of the company that ran an AS/400 was usually very small and had a lot of autonomy.
racingmars 5y ago
To be nitpicky -- The AS/400 is not a mainframe, it's what IBM calls a "midrange system" positioned between commodity x86 servers and mainframes. Today, the AS/400 OS (OS/400, or as it's known now, IBM i) runs on IBM's POWER servers. For a typical IBM i system you're talking a couple 10s of thousands of dollars, for a typical mainframe you're in the hundreds of thousands. Also regarding the power of mainframes: in the case of AS/400, it's definitely not what I would call fast. Everything runs on what is essentially a virtualization layer... the AS/400 instruction set (MI, or "machine interface") doesn't exist in any hardware, it's just run on top of a translation layer on top of (these days) POWER. It's a very weird system from top to bottom. As for actual mainframes, traditionally the power came not from raw CPU power, but from an architecture that efficiently handles parallel I/O. Definitely powerful for batch processing of large amounts of data, but not necessarily optimized for something like games.
- Yuioup 5y ago
  Is AS/400 Open Source?
  - skissane 5y ago
    No, it is a closed source IBM product. I've seen copies of its installation media on "warez"/"abandonware" sites before, but there is no emulator for it so you can't run it unless you have real hardware. IBM has recently got quite keen on porting open source software to its Unix compatibility environment (PASE) – it is a way for IBM to make it feel fresher and more modern and more accessible to mainstream developers, for only a modest investment of resources. Even if you download the installation media from one of those sites, you can't run it because there is no emulator for it. Now, it is POWER, so in principle there could be an emulator, but QEMU only supports running Linux and AIX, not IBM i. Probably if someone wanted to, they could enhance QEMU to support running IBM i, but it would be a lot of work – IBM i exploits various obscure features, not just of the CPU, but also of the firmware, which AIX doesn't, and so understandably QEMU/etc don't implement those obscure features. Commercial emulators don't really exist either, because if you start selling a commercial emulator, it is almost guaranteed IBM will sue you. I think an emulator for the classic CISC hardware would be really cool – probably make the most sense to start by emulating System/38, then try to extend it to CISC AS/400. Who would ever carry out such a gargantuan and pointless task? Probably some day, eventually, someone will do it. And it will be cool. There were commercial third party emulators, of sorts, for the System/38, such as California Software Products' Baby/38 package. However, Baby/38 wasn't full system emulation, it was actually just an RPG compiler which supported the System/38 dialect, and had a limited emulation of OS services which RPG programs commonly used. They later followed up with a successor, Baby/400. I'm sure it was quite useful to people back in its heyday of the 1990s, trying to port their RPG business applications to Windows. Practical, but not very interesting from a technology perspective.
jacquesm 5y ago
Because they cost a ton of money to own and operate, and because they typically lacked graphical output, either in real time or at all. But that didn't stop programmers from writing games for them, those just didn't enter distribution, they were typically just run locally.
Lutzb 5y ago
I remember IBM mainframes being used as a backend for the MMO Taikodom by Hoplon entertainment. https://en.m.wikipedia.org/wiki/Taikodom https://en.m.wikipedia.org/wiki/Taikodom

icedchai 5y ago

Back in the 80's and early 90's, my uncle's company had an IBM System/36, which was a predecessor to the AS/400. They used it for accounting. The thing was a monster, and it looked exactly like the top photo on wikipedia: https://en.wikipedia.org/wiki/IBM_System/36 https://en.wikipedia.org/wiki/IBM_System/36 It had 8 terminals attached, and a couple of huge line printers. We opened up the main system cabinet one day, and the hard drive (about 200 megs?) was over a foot wide. The system also used "disk cartridges" which were several 8 inch floppies in a box. Supposedly the system cost almost $200K (in 80's money.) In the mid 90's they replaced it with PCs.

jacquesm 5y ago
As drive packs come those were pretty compact already. Prior to that a 200 meg pack + drive would be the size of a top loading washing machine. Packs were removable, you'd screw them into place with a handle at the top and after closing the lid they'd spin up. Massive gear, a pack of 11 platters weighed a couple of kilos and would spin up to several K rpm, and woe to you if the pack was written on a drive with a different alignment, then you'd have to get the heads re-aligned. This was one of the reason why most machine to machine data transfer was done using tapes. Slower, but more reliable and much, much cheaper. Packs would usually stay within the same datacenter, and likely would be assigned to the same drive though theoretically there was no reason why they couldn't be moved to a different one that had been calibrated with the same calibration setup.
teh_klev 5y ago
Back in the 90's I worked as a field engineer and had a few of these on contract. They're really nice machines to work on and a common task was replacing these hard disks when they failed. The IBM field service manuals were pretty good and you could repair/replace pretty much anything on-site. They look like monsters but they're actually really friendly to field service techs.