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Please note also - THIS BLOG ENDS HERE WITH THE LAST ENTRY FROM NOVEMBER 9th 2021.

I have prepared a new blog with wordpress at https://vintagecomputing.info !!!

Thank you.
Andrew Kay passed away, one of the greatest computer pioneers of the 80s 
Saturday, September 6, 2014, 07:21 PM
Posted by Administrator
Andrew Kay died yesterday in Vista, California. He got 95 years old.
See also for a homage at >NY Times<.
For an overview of the most known computers he designed, see also >my KAYPRO pages<.
For a >recent photo of him<, visit the above mentioned NY Times page also.

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Offtopic but important: Campaign against PGP - hidden reasons ? 
Monday, September 1, 2014, 06:00 PM
Posted by Administrator

If you follow >Bruce Schneier's blog<, you will notice an >unusual entry<. He agreed with another blog entry about PGP from Matthew Green which was titled >"What's the matter with PGP?"<.
Matthew Green complained about usability and key management of PGP (... but mainly related with email), but he didn't gave any proof about a lack of (IT) security. Instead, he just spoke ill about using PGP and email in general.
If he is a cryptographer, why is he doing that ? I mean he can point his finger at real faults or errors, or at least weak spots in algorithms and methods. But he didn't.
He 's talking about cumpersome processes related with PGP. But it's related with the design of the "Web of trust". It's not really a fault.
Do you trust central key storages in cloud solutions ? That's awesome for secret services, because they will find standardized environments with large amounts of data at once, sure.
What is the alternative solution ? S/MIME for email ? Still not manageable for a "normal" user. Also, you have to trust a central provider you don't know (and may be a secret service has already access to that central provider).
If I just want to have data integrity, and I want to make sure no one else except me and my communication partner can read my messages, PGP is still a good choice. That's my opinion.
And I am disappointed about Bruce Schneiers posting such an unqualified blog entry without any further reflection. Not sure about his intention ... except there is a hidden agenda behind it.
This can be similar to the "truecrypt case". Someone (guess who) don't want that users encrypt their data in a secure manner, so they discrediting the unwanted solution. Instead, you should use "Bitlocker". Lol, be honest, that's NOT a solution I will trust. It's closed source. They could implement whatever they want. Think about >"key escrowing"<.

I am still trusting - >like Phil Zimmermann< - at least Open Source implementations of PGP, because I still see no legitimate reason why not.

And I am not alone with my opinion about Mr. Green's blog entry. See >Aaron Toponce's Blog Entry< also.

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Expirience made with Genius G840 IC Programmer (from stg51.com) 
Saturday, July 19, 2014, 12:00 PM
Posted by Administrator
A few weeks ago, I obtained a Trantor T130 SCSI ISA 8-Bit controller, and I realized I had to burn an EPROM and also a PAL/GAL chip (both were missing), see >this< blog entry also.
I burned successfully the ROM content, this was easy.
Now I tried to burn also GAL chip, but I run into problems - I guess the chinese programmer can't interpret some JEDEC files or there is a problem with the JEDEC file itself.
Everytime I load the JEDEC file (download from >a vintage-computer blog entry<, included in the attached T130B.ZIP), I see no changes in the Data View window.

I tried to convert the JEDEC file into a binary one, using the JEDUTIL.EXE which is included in the MAME distribution. I got a file with 279 bytes - seems to be wrong also.

Also, I was unsure about the sum of fuses for a 16V8 GAL, but (meanwhile) this seems to be not the problem. I tried also another JEDEC file from http://www.princeton.edu/~mae412/HANDOU ... /EMP21.jed ... this worked, loading it shows also changed data in the data window!

This chinese programmer software (I got version 5.2 which seems to be the newest one) has an ugly user interface and the english translation was not really successful done. Also, some functions can't be used intuitively, e.g. to read a device, you have to choose "CONNECT" first (why not connect the device automatically when "read" is selected ?).
Also, the "programming sequence" let me think about it again.


I have to ask other users of these G540/G840 programmers for their expirience I guess...

See related link for the JEDEC file I can't use.

Added later:
>I have modified the non-working JEDEC file<, and as a result of it, I can load it into the programmer now. 2194 fuses seems to be correct, because these additional fuses (compared to 2048 fuses user data) are not used for normal data, instead, for managing content and special parameters.

I also figured out (again later) that the G840 programmer should not ENCRYPT it as a last step, otherwise a comparison with the loaded content (into buffer) will not work too.
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Installing XENIX 386 on a real intel 486 PC Part 4 (cont'd with a 3Com503) 
Saturday, July 12, 2014, 06:53 PM
Posted by Administrator
After swapping the WD8013 card with a 3Com 3C503, I continued to install TCP/IP package.

You have to install STREAMS first - before TCP/IP, as usual with "custom" and "Add package" (Option '4'). It's a different serial/key combination compared to the TCP/IP package itself.

After you've added STREAMS, you can go on with TCP/IP Disk 1, start again "custom" and choose also "Add package" (Option '4'). After inserting all 3 Disks plus the TCP/IP maintance disk and entering again the serial/key combination (but now the one for TCP/IP), you've not finished it.

I read in a PDF document that also a SCO LLI Driver Disk (the hardware related part) was needed. You can find a version 3.0 of that LLI disk at ftp://ftp.sco.com/pub/EFS/efs120.Z (uncompress it with WINRAR for example, you will get a 1200KB (disk) tar file - copy it with doscp later from a 1.44MB DOS formatted floppy disk and rewrite it back with dd, like described in part 3 of my Xenix blog entry).

Unfortunately this LLI driver disk version 3.0 resulted in a version warning ("LLI should not be installed in any releases prior to 3.2.1." - not sure where to get a proper SCO LLI driver disk which fits for Xenix 2.3.4 ..... I WAS STUCK !


Looking for a "LLI driver disk" I found a bit later a hint, that XENIX 2.3.4 does not need and use a LLI driver disk ! I felt being framed from that above mentioned document.

So I looked for some help about using ifconfig with XENIX, and finally I found a really helpful page (here and later this one).
They mentioned to use mkdev wdn, but I looked at /usr/lib/mkdev and found the proper file was named "3comB". "mkdev 3comB" started the setup for the card and later on the kernel was rebuild also.
But 'ping' still generates 'ping: socket: Protocol not supported' .... bummer
Also, ifconfig still does not work - "ifconfig /dev/3comB0" says "invalid argument" ...

At the end I tried also "mkdev tcp" and that was the key for success !
With "mkdev tcp" you can setup your machines IP address as well as other important parameters. And after another reboot, even PING worked, and so also ifconfig 3comB0:


YES. FINALLY TCP/IP IS UP AND RUNNING WITH XENIX !!!!

If you google for "mkdev tcp", you will find several .doc files, which are located in a SCO driver directory and also existing are drivers there (e.g. ftp://ftparch.emu.edu.tr/Programs/Drivers/lan/EZ2000/SCOUNIX/ or http://download.modem-help.co.uk/mfcs-L ... e=#archive). So I guess it would be possible to run a NE2000 card also with XENIX.

Note: The related link below (a PDF at tenox.net) was NOT helpful. It describes a very different installation procedure for a later SCO UNIX version.
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Installing XENIX 386 on a real intel 486 PC Part 4 (at least the prerequisites) 
Sunday, June 29, 2014, 11:00 PM
Posted by Administrator
May be you know already, that the "Streams and TCPIP" packages does support only very few network cards, a 3COM 3C501, 3C503, WD8003 (8 Bit ISA) and last but not least hopefully also a WD8013 (16 Bit ISA). No NE1000/NE2000 support (SCO list a Novell (Exelan) 205T - but never heard before from it until I read the below mentioned compatibility note), although I read a usenet article which describes success with a NE2000 compatible Longshine card. See also here for more NE2000 comments.
So you do not need only the 4 TCP/IP floppy disks (and one Streams floppy disk), but also compatible hardware. I was so happy to find a WD8013 a few weeks before, also because these network cards are meanwhile very rare.
But I was also surprised about the size of the card - it's a monster:

The related link below mentions h/w compatibility - described by SCO itself.

Added later:

These WD80x3 cards are crap. Unbelievable how many problems occur with the configuration.
May be the Trident VGA in my 486 is the reason, don't know.

So I inserted my WD8003E (because the WD8013 didn't run, I took the WD8003 for further tests) in my IBM PC/XT, also because my XT does NOT have memory above 9FFFFh.

The default settings for these cards is i/o 280h, irq 3, ram address D0000h.
But almost all PCs of that era could have a second serial port.
So I have a big problem:
IRQ 2 = already taken by the SCSI card.
IRQ 3 = already taken by COM2 port (I have one)
IRQ 4 = already taken by COM1 port
IRQ 5 = already taken by LPT2 (I have also one)
IRQ 6 = Floppy disk
IRQ 7 = already taken by LPT1

At this point I realized I couldn't test further because my XT has no free IRQ.
So I disabled my COM2 port first (IRQ 3 is free then).
I was able to run DIAGNOSE with this result:

BUT. I was still not able to run EZSETUP.

At this point, I am out of any helpful idea.

So far I was also able to run the packet driver 8003pkdr.exe without errors.
I guess I will use the WD card with my XT, and continuing to test XENIX with my 3COM503.
May be there exist also an earlier (non SMC) WD8003 setup program, but I can't find it.
[this will be continued]
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