December 19, 2020

First MightyFrame CTIX Software QIC Tape Images on bitsavers!

They appear to be mis-categorized under MiniFrame, so without this page to redirect you, you might not find them....But we are thankful they are there!

Special thanks to NeXT on the forum for saving and imaging these tapes, and as always, Al Kossow and Bear who run Bitsavers...thank you all!


December 5, 2019

Convergent Workslate YouTube Videos

These videos are not mine, but this is the first time I've seen anything from the channel Hey Birt!...but I wanted to give my congratulations, applause, and support to him for being (what I believe to be) the first person to create a comprehensive detailed & technical YouTube video about a Convergent Technologies device (not counting the AT&T Unix PC, manufactured by Convergent), other than myself.

So, here's to you, HeyBirt!  Keep up the great work!

August 25, 2019

MightyFrame EPROM

The Convergent MightyFrame EPROM read/dump.

Somewhere, back in 2014, I remember Al Kossow giving me an EPROM dump of the Computer History Museum's MightyFrame S/80 EPROM dump, and we compared it to both of my model S/320 EPROM dump files, and they were identical.

But I went looking for that file last night, and couldn't find it, which prompted me to create a page here, on my own site, dedicated to the storage (and subsequent downloading) of the EPROM read from both of the EPROMs of my MightyFrame S/320.

And yes, they are indeed identical.  So why put them both here, instead of oly 1 of them?  Just for fun I guess...and silly redundancy...

So, here they are...for your downloading and disassembly pleasure....

June 2, 2019

MiniFrame Parts Found!

Vintage 1984 Convergent MiniFrame motherboard, 512KB RAM, 10 MHz Motorola 68010

Below are the seller's words, directly from his auctions.  Too bad, I private messaged him, to tell him I would have gladly bought a fully assembled MiniFrame and gone to his location for local pickup.  Another one of these rare machines (partially) bites the dust...but we'll save and resurrect what remains!

Motherboard from a Convergent MiniFrame Unix PC from 1984, 512KB RAM, Western Digital MFM controller, dual serial ports, 10 MHz Motorola 68010 CPU.

Here is the motherboard from a 1984 Convergent MiniFrame, which was a Unix tower designed by an important company which in 1988 became the network systems division of Unisys.  Convergent Technology helped develop the smaller but similar AT&T PC-7300. 

The person who found a Convergent MiniFrame for me in late 2017 didn't think anyone would pay shipping for a the large heavy case and power supply, so he removed the motherboard, memory cards, cluster board and 69MB Micropolis MFM hard drive only, discarding the rest.  I have no way to tell if this is working or not, but it is an interesting and hard-to-find piece of hardware from 35 years ago.   It is easier to find online documentation about the Convergent MiniFrame than it is to find parts of one.  I am happy to answer questions to the best of my ability. 

The processor is a socketed 10 MHz Motorola 68010.  There are also sockets for the Western Digital hard drive controller chips, Intel D8724 serial controller, AMD P8253 programmable interval timer and 41 more socketed chips.  The onboard RAM consists of 72 soldered-down NEC 64 kilobit DRAM chips (512KB total).   The 100-pin header and large metal rectangular support are for memory expansion and I/O cluster boards (which I will list separately on eBay).   One edge of the motherboard has two 20-pin headers and one 34-pin connector for cabling for two hard drives.  There is also a 34-pin connector for a floppy drive cable.  The back side of the motherboard has two female DB 25 ports labeled "Channel 0" and "Channel 1" (serial ports for terminals?) and a parallel printer port plus a DB9 female connector labeled "Cluster" which is for attaching one of Convergent's RS422 terminals.

2 Vintage Convergent Technologies Miniframe 512KB RAM cards + Ethernet board

2 512KB RAM expansion boards and an RS422 Cluster board from a 1984 Convergent MiniFrame Unix PC from 1984

January 13, 2018

Convergent Technologies-branded Model S/50 "AT&T" UNIX PC "3b1"

Yes, these were indeed manufactured by Convergent Technologies for AT&T...most of them, except for a few, that they "kept" for themselves, and called them Model S/50.  About the AT&T Unix PC, many say they were "functionally equivalent" to the MiniFrame.  And that relation is why we have been so interested in them here.

But here is an example of one that is actually branded "Convergent" on the front, instead of AT&T.

(Unfortunately, I missed this auction!)

August 30, 2017

Convergent Technologies MiniFrame Found!

Just a few days ago, in the mfm-discuss Google Group, Frank Hintsch in Hamburg, Germany, asked for some help imaging the MFM hard drive on his Convergent Technoloties MiniFrame.  We were VERY excited to see this message pop up, because before this week, we haven't been able to find any surviving MiniFrames.

As of today, this MiniFrame is the only confirmed survivor that we have found.

Do you have a MiniFrame hidden away somewhere?  If so, please let us know!  Either way, please enjoy the pictures and story below.

For those of you who are Convergent Technologies Alum Facebook Group members, we have a discussion going about this over there.

So here it is, in Frank's own words:

I bought it in 1985, worked with it some years (software developing), then it was stored away in the basement. Now I had the time to recover this nice machine. It is starting, booting and prompting for login! But dam it! I forgot the root (and any other) password!
I discussed this problem with the German forum for "classical computers" [on] (it's like america's VCF). The conclusion is: Read in the hard disk with MFM emulator and try a decryption of /etc/passwd entries.

March 26, 2017

August 19, 2016

InfoWorld - July 23, 1984: Convergent Technologies designs computers for name-brand makers

Convergent Technologies designs computers for name-brand makers

This is a fantastic article that a friend just pointed out to me.

It chronicles some company insights and culture into a time when the MiniFrame had just been developed, and just on the cusp of the "secret" Convergent-built AT&T UNIX PC 7300 project. 
Two MiniFrames

Steve Blank has a strong presence even today.  I love his writings of:
(where Steve actually hyperlinks this very article)

August 14, 2015

QIC-24 Tape Data Block Format Decoding & Analysis

Please also visit

So far, it seems that the comprehensive details of how the magnetic flux transitions are arranged on QIC tape using the QIC-24 standard, have been lost in the halls of time, and never made it to the internet, at least not in a complete way.

In my opinion, should be the most likely to have this information, but they seem lacking in the QIC-24 (and QIC-11) department.

Well, I am hoping that this page will fill in a lot of the missing information about QIC-24 tape format.

Before diving in, I wanted to clarify some of the "standard" terminology that surrounds this very mid-1980s QIC tape technology.  I've tried to simplify the definitions, and I put them in my own words.

QIC-24 is a tape data read/write format, defined best by 

August 7, 2015

MightyFrame Games Download

I discovered last night, immediately after setting up my vintage UNIX/CTIX display in the Whiskey Pirate Crew room at DEFCON 23 (2015), the crowd has spoken!  What do all of you hackers want to see?  Vintage MightyFrame games!

So, as a tribute to Whiskey Pirate Crew's hospitality and welcome of my vintage UNIX display at Defcon 2015, here they are:

found in the CTIX 5.25.1 factory-fresh install.

On the MightyFrame, these games reside at /usr/games

August 5, 2015

MightyFrame Peripheral Mounting Brackets

If you ever come across a full-height MFM hard drive or QIC tape drive with this style of mounting bracket, chances are that it came from a Convergent Technologies machine, most likely a MightyFrame.  Please drop us a note if you ever come across any of these:

MightyFrame S/320 Tape Drive mounting bracket

(The hard drive mounting bracket for this machine was misplaced when it was first removed)

July 11, 2015

Wangtek 5099 Tape Drive Main Board #30509 "Tap-In"

In an effort to eventually build a device that reads raw magnetic flux transitions on all QIC-11 and QIC-24 tape formats (plus a few others, hopefully), this page is dedicated to the analysis of the technical design and circuitry of the Wangtek 5099 Tape Drive with Main Board Assembly #30509.

The most comprehensive manual for this tape drive is the 


Before we begin, I'll point out that the main card-edge connector on this board seems to contain the connections necessary to at least read "data pulses", which would be the interpretation of the magnetic flux transitions on the tape.  These are standard pins on a QIC-36 interface, which seems to be what the main connector on this board provides
Pin 2 - Go
Pin 4 - Reverse
Pin 26 - Data Read Pulse
Pin 38 - Tachometer

June 14, 2015

Wangtek 5099 Controller Board #30425 for QIC-02 interface

I'm trying to get a Wangtek 5099 to work with my MightyFrame.

Right now, the MightyFrame uses an Archive 5945, but that only reads 60Mb 9-track QIC-24 tapes.  I want to read older 20Mb 4-track QIC-11 tapes, thus the attempt to switch to the Wangtek 5099, which has the physical hardware capability of reading those.

So, here's what I've discovered so far on my MightyFrame with it's original tape drive: 

Motherboard -> Tape Drive Interface Board -> Archive 5945L


Motherboard -> Tape Drive Interface Board = QIC-02 interface

and where

Tape Drive Interface Board -> Archive 5945L = QIC-36 interface

June 7, 2015

MightyFrame Motherboard Jumpers

This board pictured is from a MightyFrame S/320, best we can tell.  (Model CG-5140)

Without any MightyFrame hardware manuals as of yet, we can only guess what these jumpers are for.  We are currently asking around.  See the discussions at: 

May 23, 2015

1986 Convergent Technologies Status Codes Manual 2nd Edition

Days ago, I missed buying this very hard to find manual on eBay.  While not directly about the MightyFrame, the fact that it references the MightyFrame and CTIX is something that would have been very important to our MightyFrame and Convergent Technologies resource aggregation efforts.

May 12, 2015

Terminator 'B' Box on 34-pin MFM Cable

The MightyFrame S/320 has a more unique 34-pin cable for connecting to its 3 available MFM (ST-506) drives.  

The 3 drives are labeled D0, D1, and D2.

The card-edge connector for each drive is clearly labeled, and missing very specific contacts, as follows:

D0 is absent 28, 30, & 32.

D1 is absent 26, 30, & 32.

D2 is absent 26, 28, & 32.

April 21, 2015

Reading & Re-Creating QIC Tapes (for the MightyFrame)

(Note that this is on modern Linux using a Tandberg TDC-3620 with SCSI card, using DC600A tapes)

To read an original tape into the current working directory using my version of straight dd, create and run a script that looks like this:
(for logging purposes, I created 2 scripts, an "outer" and and "inner" script, named tapef and tapefslave respectively)

March 16, 2015

MightyFrame CTIX 5.25.1 install tape restored and used

Just this past week, I was able to image the first MightyFrame CTIX Install Tape that I've ever had access to.  (I used this process.)

5.25.1 S/120-22X-320 CTIX RAW/UPDATE 16USER

Many thanks to the generous donation of vintage CTIX cartridges from Mario at!

February 3, 2015

MightyFrame cpio demystified

I personally find cpio very confusing, and I hear that I'm not alone.

When working with the UNIX PC previously in this endeavor,  I abandoned trying, because someone had provided a working version of tar for the 3b1 (MC68010 processor).

However, when I started this post, I couldn't find the equivalent for the MightyFrame MC68020 processor.  I thought that now I must break down and learn how to use cpio.  Since then, Tom has pointed out that it is actually there, at /usr/bin/tar.  But, I found other reasons that I need cpio, such as copying an entire file/directory structure.  So, here is my analysis, such that it is:

February 1, 2015

MightyFrame: Creating A Boot Tape

First, write the VHB with bootloader, as shown in an earlier post:

sudo dd if=vhb.miti.tape.slice1.dd of=/dev/nst0 

The "nst0" tells the tape not to rewind after writing each file, or something like that.

(Note that this is on modern Linux using a Tandberg TDC-3620 with SCSI card)

Then, add the CTIX kernel after that.  We had to "adjust" the length of this file by padding the end with sets of null bytes (Hex Value 00) until the file reached exactly 396 blocks, otherwise, we got an error saying that 395+1 blocks read, 395+0 blocks written, or to that effect.

January 26, 2015

MightyFrame Formatting Maxtor XT-2190 followed by mkfs

screen took us SO long to get here.

Working with Sasa via Skype, I figured out how to trick the MightyFrame to format a Maxtor XT-2190 (physical) hard drive on D1, while the MFM Emulator ran the OS on D0.  

January 22, 2015

Creating MightyFrame /dev devices using a script on the UNIX PC

Tom Trebisky has done a marvelous job assisting us in this project.  We simply could never have gotten this far without his patient, dedicated help.

One of countless gems, Tom created this shell script to run in the /dev folder on the UNIX PC, where /dev is on slice 1, and contains other MightyFrame os files.

January 15, 2015

MightyFrame first login date: 01/14/2015

I quite literally by accident, got a command prompt on the thing for the FIRST time since I started this project!

(warning...lengthy, seemingly endless, wandering terminal screen captures follow)

January 12, 2015

Customizing inittab and rc files for boot diagnostics

The following files are customized to diagnose how the MightyFrame is executing my customized /etc/inittab and /etc/rc files while attempting to boot a version of CTIX5.11onb modified by Sasa Todorovic and renamed to CTIX5.11dbg