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MAI Basic Four anyone?

VERAULT said:
Again, your replying to a post from 2 and a half years ago. That member only posted here twice and hasn't been seen in almost 2 and a half years. I dont think your going to get a reply.
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There are still current active members who have contributed to this thread in the past...
 
btb said:
I just had a 7250 terminal fall into my lap. Unlike the other ones I've seen in photos, this one is blue:
View attachment 1249432
It seems to work, mostly. A bit of garbage on the screen, so maybe some failing ram. I'd love to find some documentation. At first I thought the 7270 must be pretty close, but nope! The 7270 is Z80-based and this one is all discrete. Pretty surprising to me seeing as it appears to have been built in 1980 and has service stickers as late as 1990.

I'm also interested in upgrading mine with lowercase. It uses a General Instrument RO-3-2513-001 character generator for uppercase, and there appear to be two empty sockets for other character sets. Could it be as easy as dropping in an eprom adapted to the right pinout?
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Following up, was working to get this terminal restored, but it's taken some steps backward. On the power supply, a TO-3 7912 regulator failed, sending around -29V into the logic board, which took out some number of components. I replaced that regulator and now I'm slowly figuring out the bad chips and replacing them. I also reverse engineered the whole logic board, finding the schematic to be very very close to that of the 7230 which is available at bitsavers. The service manual for that machine is also starting to come in handy.

The front panel is made of acrylic or something similar, and is pretty hazy. I imagine I will have to try to carefully polish it.
 
Caluser2000 said:
There are still current active members who have contributed to this thread in the past...
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I worked at MAI/Basic-Four 1988-1990 at the Corporate campus in Tustin, CA. Really enjoyed working there. I've enjoyed reading these threads, looking at the pics
 
JeffC said:
I worked at MAI/Basic-Four 1988-1990 at the Corporate campus in Tustin, CA. Really enjoyed working there. I've enjoyed reading these threads, looking at the pics
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Welcome to the Forum Jeff. Would love to hear some stories from you.
 
Decades ago, I worked for Thoroughbred Software and they owned an MAI BASIC Four computer. They are still in business. https://www.thoroughbredsoftware.com/ . It had two removable disk drives, a system unit and a terminal.. Before I started working there, somebody went to make a backup, copying one disk to the other, and got the order wrong.

The history of Thoroughbred, as I was told, is that Concept Omega had created accounting software for the BASIC Four but wanted to sell it on other platforms. They could have rewritten the accounting software, but instead decided to clone the BASIC Four operating system which they named Thoroughbred.

I would be surprised if that BASIC Four ended up in the trash, but not very surprised. :)
 
RickPoleshuck said:
Decades ago, I worked for Thoroughbred Software and they owned an MAI BASIC Four computer. They are still in business. https://www.thoroughbredsoftware.com/ . It had two removable disk drives, a system unit and a terminal.. Before I started working there, somebody went to make a backup, copying one disk to the other, and got the order wrong.

The history of Thoroughbred, as I was told, is that Concept Omega had created accounting software for the BASIC Four but wanted to sell it on other platforms. They could have rewritten the accounting software, but instead decided to clone the BASIC Four operating system which they named Thoroughbred.

I would be surprised if that BASIC Four ended up in the trash, but not very surprised. :)
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Hi Rick, thanks for replying. Can you help us get a hard drive formatted to work with our GPx systems? I can get the same model number from ebay but they won't take configuration file due to formating problems. I have the tape to format but the biv code doesn't work.

On our backup system the monitor won't show any characters. It sounds like it boots up but we can't see what's happening.



Thank you
 
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RickPoleshuck said:
Decades ago, I worked for Thoroughbred Software and they owned an MAI BASIC Four computer. They are still in business. https://www.thoroughbredsoftware.com/ . It had two removable disk drives, a system unit and a terminal.. Before I started working there, somebody went to make a backup, copying one disk to the other, and got the order wrong.

The history of Thoroughbred, as I was told, is that Concept Omega had created accounting software for the BASIC Four but wanted to sell it on other platforms. They could have rewritten the accounting software, but instead decided to clone the BASIC Four operating system which they named Thoroughbred.

I would be surprised if that BASIC Four ended up in the trash, but not very surprised. :)
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Welcome to the Forum Rick!

@GFlamand Best you remove your phone number and send a PM to @RickPoleshuck unless you want the spam bots to put you on every telemarketer list known to man.
 
GFlamand said:
Hi Rick, thanks for replying. Can you help us get a hard drive formatted to work with our GPx systems? I can get the same model number from ebay but they won't take configuration file due to formating problems. I have the tape to format but the biv code doesn't work.

On our backup system the monitor won't show any characters. It sounds like it boots up but we can't see what's happening.

Thank you
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I worked at a company that may still have a working BASIC Four and included a link to their web site. I stopped working there in 1989, 35 years ago. Sorry, but this is the most help I can provide.
 
Bonjour Rick, merci d'avoir été. Vous pouvez vous aider à trouver un disque dur pour qu'il fonctionne avec nos systèmes GPx? Je peux obtenir le jour numéro de modèle d'ebay, mais ils ne prennent pas le fichier de configuration en raison de problèmes de formatage. J'ai la bande à l'ancien mais le code biv ne fonctionne pas.

Sur notre système de sauvegarde, le moniteur n'affiche pas. On dirait que ça demarre mais on ne voit pas ce qui se passe.

Bonjour, bonjour,
J'ai peut-être les connaissances nécessaires pour former un disque dur, mais qu'entendez-vous par "biv"?

Mon adresse amgsr79@aol.com
J'attend la signification de 'biv' sur ce post

Cordialement Alain-Marc
 
Tournesol_France said:
Bonjour Rick, merci d'avoir été. Vous pouvez vous aider à trouver un disque dur pour qu'il fonctionne avec nos systèmes GPx? Je peux obtenir le jour numéro de modèle d'ebay, mais ils ne prennent pas le fichier de configuration en raison de problèmes de formatage. J'ai la bande à l'ancien mais le code biv ne fonctionne pas.

Sur notre système de sauvegarde, le moniteur n'affiche pas. On dirait que ça demarre mais on ne voit pas ce qui se passe.

Bonjour, bonjour,
J'ai peut-être les connaissances nécessaires pour former un disque dur, mais qu'entendez-vous par "biv"?

Mon adresse
J'attend la signification de 'biv' sur ce post

Cordialement Alain-Marc
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The same goes for posting your email address. You are welcoming thousands of junk mails.. Send A private message if you have private information. This is nothing new.


EDIT: BEST YOU REMOVE THAT EMAIL ADDRESS ASAP. If too much time has passed contact an admin to remove it for you @ajacocks




.......and the internet used to be such a nice neighborhood to live at one time.
 
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VERAULT said:
The same goes for posting your email address. You are welcoming thousands of junk mails.. Send A private message if you have private information. This is nothing new.


EDIT: BEST YOU REMOVE THAT EMAIL ADDRESS ASAP. If too much time has passed contact an admin to remove it for you @ajacocks




.......and the internet used to be such a nice neighborhood to live at one time.
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I appreciate your concern. It does make me feel safer. But vcfed.org is unlikely to be the only forum where these people have posted their emails and phone numbers. :)
 
RickPoleshuck said:
Decades ago, I worked for Thoroughbred Software and they owned an MAI BASIC Four computer. They are still in business. https://www.thoroughbredsoftware.com/ . It had two removable disk drives, a system unit and a terminal.. Before I started working there, somebody went to make a backup, copying one disk to the other, and got the order wrong.
Click to expand...

That was probably an old one with a Microdata CPU and a Diablo 44 disk drive. I still remember Clock / Reset / Run was the front panel operation to boot.

The Diablo 44 was a 10MB 5-over-5 removable 5440 on top and a fixed platter on the bottom. The backup sequence, which had to be followed EXACTLY, was:

1) Spin down disk, remove production top pack
2) Insert scratch pack, labeled "Bottom Backup mmddyy" or something similar, and spin up the drive
3) Copy the bottom to the top, spin down and remove Bottom Backup pack.
4) Insert production top pack, spin up
5) Copy top to bottom
6) Spin down, swap out production top pack
7) Insert scratch pack labeled "Top Backup mmddyy" and spin up
8) Copy bottom to top
9) Spin down, remove Top Backup pack
10) Insert Bottom Backup pack, spin up
11) Copy top to bottom, spin down
12) Swap Top backup pack for production top pack, spin up
13) Pray that you didn't screw up

This couldn't be automated because there was a reboot between pack changes (both the production top and the bottom were bootable, so there should always be at least one bootable platter in the drive.

It was quite a relief when the system was updated to a MAI-built CPU with a pair of Calcomp T25 drives.

Back then, OS updates (which included both the OS and the BASIC language interpreter) were delivered on packs that had to be returned. The software was called BOSS (Basic Operating System Software, I think). We used to say "Meet the new BOSS, same as the old BOSS" (from The Who's "Won't Get Fooled Again". That involved a simplified version of the 13-step shuffle to make sure both the top and bottom had the same BOSS version on them.
 
Terry Kennedy said:
That was probably an old one with a Microdata CPU and a Diablo 44 disk drive. I still remember Clock / Reset / Run was the front panel operation to boot.

The Diablo 44 was a 10MB 5-over-5 removable 5440 on top and a fixed platter on the bottom. The backup sequence, which had to be followed EXACTLY, was:

1) Spin down disk, remove production top pack
2) Insert scratch pack, labeled "Bottom Backup mmddyy" or something similar, and spin up the drive
3) Copy the bottom to the top, spin down and remove Bottom Backup pack.
4) Insert production top pack, spin up
5) Copy top to bottom
6) Spin down, swap out production top pack
7) Insert scratch pack labeled "Top Backup mmddyy" and spin up
8) Copy bottom to top
9) Spin down, remove Top Backup pack
10) Insert Bottom Backup pack, spin up
11) Copy top to bottom, spin down
12) Swap Top backup pack for production top pack, spin up
13) Pray that you didn't screw up

This couldn't be automated because there was a reboot between pack changes (both the production top and the bottom were bootable, so there should always be at least one bootable platter in the drive.

It was quite a relief when the system was updated to a MAI-built CPU with a pair of Calcomp T25 drives.

Back then, OS updates (which included both the OS and the BASIC language interpreter) were delivered on packs that had to be returned. The software was called BOSS (Basic Operating System Software, I think). We used to say "Meet the new BOSS, same as the old BOSS" (from The Who's "Won't Get Fooled Again". That involved a simplified version of the 13-step shuffle to make sure both the top and bottom had the same BOSS version on them.
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This was a long time ago. There were two separate removable disk drive cabinets. I referred to them as Cuisinarts, because I thought the removable platters were changeable like really big Cuisinart blades. :) As I remember, these were 40 megabytes each, one per cabinet. This computer was only used for development, so it may not have been configured in a way that made sense in a production environment.
 
RickPoleshuck said:
This was a long time ago. There were two separate removable disk drive cabinets. I referred to them as Cuisinarts, because I thought the removable platters were changeable like really big Cuisinart blades. :) As I remember, these were 40 megabytes each, one per cabinet. This computer was only used for development, so it may not have been configured in a way that made sense in a production environment.
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Those sound like CalComp Trident T-80 drives. They were normally on rails so they could be slid out of a rack to change the packs, but MAI put each one on top of a free-standing cabinet, perhaps to make them look more impressive. MAI sold them as 40MB, and when a friend was proudly showing off his office's new system, he showed me the "40MB" drives. I said "Those are CalComp Tridents, and CalComp doesn't make a 40MB." Sure enough, I went around the back and the CalComp nameplate said T-80. Apparently the customer was in the process of negotiating with MAI for the "80MB upgrade" on those drives, and those negotiations went downhill fast once the customer realized the drives were already 80MB units. I believe they eventually negotiated a minimal price for the "upgrade".
 

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Terri Kennedy said:
Those sound like CalComp Trident T-80 drives. They were normally on rails so they could be slid out of a rack to change the packs, but MAI put each one on top of a free-standing cabinet, perhaps to make them look more impressive. MAI sold them as 40MB, and when a friend was proudly showing off his office's new system, he showed me the "40MB" drives. I said "Those are CalComp Tridents, and CalComp doesn't make a 40MB." Sure enough, I went around the back and the CalComp nameplate said T-80. Apparently the customer was in the process of negotiating with MAI for the "80MB upgrade" on those drives, and those negotiations went downhill fast once the customer realized the drives were already 80MB units. I believe they eventually negotiated a minimal price for the "upgrade".
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As I remember the two disk drive units were about the same size and shape as the system unit. But I am now reminded of the story that my friend and former coworker told me. The BASIC Four technician came out to upgrade the disk drive from 40Mb to 80Mb. My friend was friendly with the technician who told him that his job was to take a long time taking the unit apart, flip a switch for the 40 to 80 mb feature and then take a long time putting the unit back together.
 
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