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Marubeni Ibex on eBay

Do you have any technical information about this system? I tried to ask the seller, but they said it was already packed in the boxes, and they didn't want to take it out.

Do you know if the floppy drives are 8"? They look like it but it's hard to tell.
 
Yup, those are 8" drives. I don't know too much about these systems, except that you'd see "Mountain Goat" ads for them. Z80 64K CP/M-based. I doubt that they did graphics or anything fancy. Just your basic commercial office box. Some of the later ones ran MP/M and could be hooked to multiple terminals.

Marubeni is still very much around--Martec morphed into Marubeni Information Systems USA, but I doubt that anyone there remembers anything about this dinosaur.

This is very clean for a 1979-80 vintage system.
 
I find this an interesting machine too. Lately I've been reading interesting back issues of Infoworld on google books. It's amazing how many weird and wonderful machines came out in the early 1980s which I've never heard of. You see them in small advertisments hidden among the pages.

Tez
 
I'd first check with the seller; there might be a boot disk with he system. There might also be some literature with the system itself.

Failing that; it's a Z80 box, after all. I'd dump the boot ROM on the thing, which would probably tell me everything I need to know to craft a CP/M BIOS.

Other information may be hard to come by. I suspect this thing was produced for the Japanese export market and might be almost completely unknown in Japan. If Don Maslin ever saw one, he never told me.
 
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mgarlanger said:
Interesting. Too bad there are no disks included.
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IMHO no matter how great a machine may be, if you can't boot it, it's value is greatly diminished. I have a DMC Commfile that I have had for about 3 years and still can't find any boot disk for it. At this point, it's nothing more than an interesting "boat anchor".
There are machines I have that need parts or software that I hang onto in the hopes that patience will win out and eventually the resources I need to get them running will show up on eBay (or maybe on this site).
 
It all depends on how much work you'd like to put into it. As I said, Z80 machines are generally pretty easy to get CP/M on. I've put CP/M on FAX adapters and modems--you basically need some sort of connection to the outside world (i.e. a serial port) and sufficient memory, as well as a conforming CPU. When 8-bit machines were first coming out, people thought nothing of rolling their own CP/M version for whatever hodgepodge of I/O cards they owned.
 
The seller states in the ad, that there are no disks. They didn't mention anything about manuals, so I'm assuming they don't have any.

Mark
 
Well, look--the thing looks to be nearly new, includes two 8" drives and what appears to be a wide-screen CRT (on the advertising literature, there is a reference to 132 character display width). If I were in Austin and the seller would waive shipping, I'd jump on it because it's rare enough. I'd have to think awhile if I was going to pay for shipping.
 
Do you have any idea on the specs for the 8" drives? If it's double-sided/double-density, I would be more tempted. Also, for 8" CP/M disks, was there a common format? I thought 8" disks were interchangable between all the CP/M systems. I know the 5 1/4" disks had MANY different formats.
 
I suspect that the drives are late enough (very late 70s-early 80s) that they're double-sided. Any 8" drive can do double-density; that's a function of the controller.

The so-called "A1" format (IBM 3740: single-density 26 128-byte sectors/track, single-sided) was the closest thing to a common CP/M interchange format. Gary Kildall considered it to be the only CP/M interchange format--if you ordered an OEM kit from DRI, that's what you got the software on. Many 8" CP/M systems can handle these, but not all of them can.

You might ask the seller what model number this is (i.e. what's on the outside of the boxes).
 
mgarlanger said:
Also, for 8" CP/M disks, was there a common format? I thought 8" disks were interchangable between all the CP/M systems.
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I'm assuming your question is: "If I buy this machine is there a standard CP/M 8" disk that will boot up most Z80 machines?" Like a MS-DOS boot diskette that will boot almost any PC-Compatible computer?
 
Chuckster_in_Jax said:
I'm assuming your question is: "If I buy this machine is there a standard CP/M 8" disk that will boot up most Z80 machines?" Like a MS-DOS boot diskette that will boot almost any PC-Compatible computer?
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So why didn't you answer the question then?

As Chuck pointed out, only 8" SS/SD diskettes are almost universally compatible in the CP/M world as far as reading and writing files goes, but there are many programs out there to convert between different formats; most CP/M software is also pretty compatible among different systems except for issues related to different terminals or displays using different codes to move cursor, clear screen, etc.

But the boot files are generally system-specific since there are no standards for disk formats, I/O port locations etc., and many systems had their own unique way of talking to the keyboard, display, disk drives, etc.

In the PC world, most of this is handled through the BIOS which is also pretty system-specific, but it is part of the system hardware and makes different systems *appear to be* the same or similar; on the other hand, in a CP/M system much of the system-specific equivalent of the PC's BIOS is loaded from a file on the boot disk at startup time and must therefore match the system's hardware configuration.

But although it can be a fun challenge to create a boot disk, it's not impossible; CP/M itself is extremely well documented and was in fact designed to be customized for different systems, and the *basic* hardware is pretty well the same for all those systems. I would also expect a commercial system to have a monitor program in ROM that would let you at least talk to the hardware, edit memory, read a boot file off the disk, etc.
 
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Chuckster_in_Jax said:
I'm assuming your question is: "If I buy this machine is there a standard CP/M 8" disk that will boot up most Z80 machines?" Like a MS-DOS boot diskette that will boot almost any PC-Compatible computer?
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Not quite... the question is: "If I get CP/M up and running on this machine, will I be able to put any 8" CP/M disks in the second drive and be able to read it?" That way, I could run communication software and transfer some software, which I have on 8" disks, to another CP/M system with 5 1/4" drives.
 
mgarlanger said:
Not quite... the question is: "If I get CP/M up and running on this machine, will I be able to put any 8" CP/M disks in the second drive and be able to read it?" That way, I could run communication software and transfer some software, which I have on 8" disks, to another CP/M system with 5 1/4" drives.
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Not to discourage you from rescuing this nice and relatively unique and rare machine, but if that's all you want to do then there are easier ways than creating boot and system disks for this machine first (assuming you have an 8" drive or know someone who does).

And in any case, of course it all depends on what format those 8" disks (and the target 5 1/4" disks) are in.
 
MikeS said:
So why didn't you answer the question then?
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Because I didn't know. I'm following this thread to try and gain some knowledge myself on CP/M and what the options are for generating a boot disk for machines you can't find ANY information ANYWHERE on the web. I spend a lot of time combing the web trying to find information on some of these old machines only to wind up with nothing. It's really frustrating.

You gave a good explanation in your last reply. I would really like to attain the knowledge you guys are talking about where I can dump the contents of ROM and be able to make a boot disk. For starters I have a couple of books on CP/M I need to study. Hopefully there will be enough "under the hood" information that I can make some headway.
 
Okay, if you're asking "is there a universal boot disk for these things (CP/M systems)?", the answer is "no". DRI supplied their 8 bit CP/M OEM distributions with a BIOS that worked with the Intel MDS-800 development system. Customers were expected to "roll their own" BIOS to match their equipment.

A side note here--when I say "BIOS", I'm not referring to ROM-resident code, necessarily. Most CP/M implementations consisted of a boot ROM that could read in a sector or a few sectors of a system boot disk. The boot loader would then, in turn, load the BIOS (I/O drivers), BDOS (the part of CP/M that implements the file system) and the CCP, or command processor. DRI supplied the BDOS and CCP; the customer supplied his version of the boot and BIOS, using the DRI sample code and the "CP/M System Alteration Guide" as references. It's usually not hard--a couple of K of code.

Now, if you have a system that as part of the boot procedure puts a signon message and reads the disk, you have pretty much all you need in the way of information to write your own BIOS. Just disassemble the boot ROM and there you have it.
 
Chuckster_in_Jax said:
Because I didn't know. I'm following this thread to try and gain some knowledge myself on CP/M and what the options are for generating a boot disk for machines you can't find ANY information ANYWHERE on the web. I spend a lot of time combing the web trying to find information on some of these old machines only to wind up with nothing. It's really frustrating.

You gave a good explanation in your last reply. I would really like to attain the knowledge you guys are talking about where I can dump the contents of ROM and be able to make a boot disk. For starters I have a couple of books on CP/M I need to study. Hopefully there will be enough "under the hood" information that I can make some headway.
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You and me both! ;-)
One of my CP/M systems is a Vector Graphic MZ which uses relatively rare and somewhat unreliable 100TPI Micropolis drives and I thought I'd try replacing them with modern 96TPI 1.2M HD drives; of course the disks won't be interchangeable, but as long as I remember which disks go into which drive it should be OK.

Well, it does indeed work, almost. I can copy diskettes back and forth from 100TPI to 96TPI, read and write files, load and run programs, etc., so CP/M has no problem with the new drives, but the system will not boot from them. I can copy a bootable diskette from the Micropolis 100TPI disk to the Panasonic 96TPI, and back to a new 100 which will boot with no problems, but it looks like there is something in the ROM boot loader that's fussier than CP/M and doesn't like those new drives; FWIW a friend with Tandon drives (and a corresponding different controller and boot ROM) in his Vector replaced them with the same drives I was using and he had no problems.

Grrr...
 
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