Silent Q

Azog's little slice of the world. Whee.

Atari Mega STe

Posted By on February 8, 2014

This is something that has been sitting in my background queue for a while, and now I’ve finally decided to tackle it. I might have mentioned this machine in passing before. Insert the warning that there are Lots of Images Ahead.


This is an Atari Mega STe. There was one major issue with it, which I’ll discuss a bit later, and while I was working on it, I decided to do a photo essay of the machine, since I personally think it’s of historic interest. If you’re not familiar with the Atari 16 bit series, I just want to briefly give some context relative to this machine. You can certainly find a better overview of the ST itself elsewhere.

In 1990, Atari released their first true 32-bit computer, the TT030. When I say “true” 32-bit, that is in opposition to the 16/32 architecture of the regular ST computers. I think the TT030 was Atari’s finest computer, even more than the Falcon030, but it had issues. Mostly price; I think they originally retailed for almost $3,000. Well out of the “home computer” market. Another issue was that it sacrificed compatibility to achieve 32-bitness, so things like games were fickle. It ran a different version of TOS, 3.xx. I don’t know if Atari planned on the TT030 being in the migration path for an ST user, but I doubt it.

Unfortunately, my TT030 is long gone, otherwise I would also do a post covering that…

The MegaSTe series was released a year later, in 1991, and retained some form and function of the TT030: the case with detached keyboard and the VME slot. Other than that, it was an STe (ST, enhanced) shoved into a TT030 case. It ran the same TOS version, TOS 2.06, as the ST series.

Immediately obvious from the above picture is the case, which had a matching detached keyboard.


It’s the same mechanical keyboard as the TT030, but it is also the same layout as the ST series had for its entire lifespan. The mouse pictured here is a third-party mouse, one that is significantly better than the stock Atari mouse. Oh, as an aside, I’ve heard rumors that you can modify Amiga tank mice to the Atari ST by just swapping two pins. Have never done so myself…

Looking at the left side of the machine reveals the typical Atari ST ports with a couple extra ports.


The reset switch, MIDI ports and cartridge ports are typical. The LAN port is the AppleTalk port that was introduced on the TT030 and stayed with the architecture thru the Falcon. Never found any use for the LAN port. I think it’s just a serial port. Anyways, there’s also an RJ45 connector for the keyboard.

Looking at the back, there is the Atari floppy port.


On a hard-drive based system, I find the need for a second floppy to be of limited use, but there you have it. Obviously someone, somewhere in time must have used it…

Next to that is the video ports, consisting of a 13-pin DIN connector, which provides color and monochrome signals (which in turn required different monitors), the RF selector switch and the RF output.


I’m not too sure how many people were still using RF video (displaying on their TV) in 1990, but again, there it is…

Then there is the ACSI port…


ACSI stands for “Atari Computer System Interface” or something, and is Atari’s butchered version of SCSI. I think drives like the SH205 were ACSI. Internally, the Mega STE has a SCSI controller.

The parallel port and two serial ports.


Then all way on the right are the stereo audio ports, one of the “enhancements” of the STE series.


I mentioned that the TT030 and Mega STE series had a VME port. Here is an extra serial port inserted into where the VME slot is accessed.


I don’t know if that was standard, or if someone was selling a serial port kit, but that means that this machine now has THREE serial ports. That’s a lot. I guess you could have run a killer BBS on this. Odd thing is, once you remove this slot, it’s nothing more than a ribbon cable going to a header on the motherboard inside.


So that’s pretty much the externals of the machine. There’s a small side-car like box on the right side of the machine, visible in the first image of this post, which is where most of the “user accessible” parts are.


The carrier sitting on top is where the hard drive lives, and that’s where my issue for this project is. Look inside, and you can see the TOS and RAM chips as well as the SCSI cable.


These are just 30-pin SIMM chips, and there are four 1mb chips, so this machine is fully populated at 4mb. SIMM chips were first used in the “regular” console version of the STE, and stayed with the series almost to the end. The Falcon030, their last computer, did NOT use any then-standard memory expansion.

There are also two TOS 2.06 chips. Again, ST models prior to the STe series used a six-chip TOS version, and in the console version of the STe, they started to use bigger sized ROMs to allow for only two chips.

Behind the memory is the SCSI controller, which is hard to see.


Now to the particular issue of this machine, is that the hard drive died. It had a 40mb (yes, megabyte) drive which started to throw lots of read and write errors.


I marked it so I would not forget the status of it. I still have not disposed of it. I’m a packrat. I have no idea why I am saving it, especially since it is failed.

Now the problem here is that once you throw the term “SCSI” around, people apparently think that should increase expectations of the actual worth. I looked around on the first place people tend to look (eBay) and didn’t really find anything suitable for under $100. I don’t need a gigabyte drive, just something with a couple hundred megabytes. I asked around on a forum, and someone sent me an identical model in supposedly-working condition for like $50, but once I set the jumpers and installed it, it did not function.

So I spent a lot of time fretting over this, which is why it took me so long to just get over. I ended up picking up a CompactFlash to SCSI adapter. They’re expensive, but by now, I’ve already spent money on something that didn’t work, and if I were to pick up a different drive, I’m already approaching the cost of the CF-SCSI adapter. There’s also the bonus that you’re using solid-state rather than mechanical drives, so failure won’t be as much of a threat. Plus it’s quieter and will put less load on the power supply. Here it is mounted in the hard drive carrier.


In the picture, it is upside down. I had to flip it over, or twist the SCSI cable. After I had everything buttoned up, I realized I forgot to connect the LED cable, which is the black/red pair you see on the left, but I’ll take it apart later and deal with it. The CF card is a “Cisco” 128mb card. You can find these particular cards on eBay in the 100’s for between $10 to $20. To install it, all I needed to do was make the device ID#0, and add termination.

Finally, all put back together, formatted, booted and showing 120mb of space. It’s a single partition.


Now all that remains is to build it into a suitable system: add the Control Panel, and maybe play with my new NetUSBee on it.


2 Responses to “Atari Mega STe”

  1. A Great Atari Computer … thx

  2. Rustynutt says:

    Thanks for taking the time to include (very clear) photos. Bought an almost new TT a few months back (mid 2015), just now having time to install upgrades collected the past few years. Turns out I bought the same SCSI to CF card as you have. Always reassuring having photos and another users documentation to go by :) Have read in “the forums” users having issues with IDE to CF adapters. AIRC, some of those adapters work only with IDE CD ROM’s. Those were likely older post/problems, seems Falcon users now have that all squared away.

    You covered termination on the adapter card, see you have a jumper on the pins the cards documentation shows as “no termination”. I know the TT has SCSI “on board” where the MegaSTe needs a daughter card for internal SCSI. Wondering if I’m reading the docs wrong and a jumper should be installed to enable termination, or if you are talking about termination packs on the MegaSTe board itself for internal termination.

    Digging the TT, installed a GE Soft fast ram card with 64mb, the machine came with a 10mb ST Ram card (that’s a hard one to find). Last week installed a Spectrum 1 TC VME card. It’s been a bit pissy setting up on a 24″ Dell LCD, is a must have though on the TT. Setting up the TT for use with Chronos Key Frame Animator, Zenomorph Raytrace and Dyna Cadd. Tried those softs on the Falcon, they are a bit glitchy. Wife just went to bed, midnight, so should have time to work on the TT/SCSI a few hours :)

    Also have a MegaSTe that’s kind of waiting in queue. It’s a TOS 2.06 w / HD Floppy. I bought an FPU GAL from Best Electronics to go with an 882. Think there was only one program that utilized the FPU on the MegaSTe, and that an 881. The MegaSTe crashed on a bench test as it was expecting an 881, there’s another “hunt” to go on.

    For SCSI on the MegaSTe thinking about opening up an ICD Link and mounting it inside to go with the SCSI to CF card adapter like you have.

    So that’s about a floppy’s worth of text! :)

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