September 6th, 2015 ~ by admin

The Electronika MK1 red3 PDP-11 Chipset and Tetris

Soviet Electronika MK1red3 - F-11 Clone and implementation of PDP-11

Soviet Electronika MK1red3 – F-11 Clone and implementation of PDP-11

The DEC F-11 ‘Fonz’ implementation of the PDP-11 was released in 1979 and was DEC’s second ‘LSI’ implementation of the PDP.  Like its predecessor it was a multi-chip implementation, consisting at its root of a data chip (DC302) and 1-9 control chips (DC303).  The DC303 control chips were essentially a large ROM/PLA with a few extra features added for interrupts and sequencing.  They formed the microcoded instruction set that drove the 16-bit ALU and registers of the DC302.  This is why more then one were supported.  Expanding the instruction set was as ‘simple’ as adding more DC303 chips with these instructions encoded.  The basic LSI11/23 came with one 303 and one 302.  A second IC could be added to support floating point, which included a pair of DC303 chips implementing the floating point instructions.  A MMU (DC304) was also supported, and required when using the FP option.

DEC 570000101A1 F11 Floating Point Option with 2x 303E Control chips

DEC 570000101A1 F11 Floating Point Option with 2x 303E Control chips

The Soviets also widely adopted the PDP-11 architecture.  Likely because it was designed to be rather hardware independent.  It could be implemented in many different ways, which meant the Soviets could adopt/implement it on their own.  Electronika was part of the Soviet industrial complex in Voronezh, Russia making many different IC’s, but also was tasked with making consumer devices (computers and calculators etc, that were in very short supply.  The Electronika 60 was one of the first PDP-11 computers they made, and it implemented a copy of the DEC Fonz processor.  Electronika combined the standard chipset, and FPU onto a single large MCM with all 4 IC’s (the MMU remained separate) called the MK1 red1 (and later the MK1 red3)

Tetris Electronika 60 - Text Only

Tetris Electronika 60 – Text Only

KH1811VM1 = DC302 – 21-15541 Data Chip (16-bit ALU etc)
KH1811VU1 = DC303 – 23-001C7 standard instruction set
KH1811VU2 = DC303 – 23-002C7 FP instruction set Part 1
KH1811VU3 = DC303 – 23-003C7 FP instruction set Part 2

It was on this chipset, on a Soviet Electronika 60 that Alexey Pajitnov wrote the very first version of the still famous game of Tetris back in 1984.  A game that was very popular, and very widely copied in the West, even to this day.  (the copying of technology most certainly went both ways)

November 21st, 2014 ~ by admin

When a Minicomputer becomes a Micro: the DGC microNOVA mN601 and 602

DGC logoThe late 1960’s and early 1970’s saw the rise of the mini-computer.  These computers were mini because they no longer took up an entire room.  While not something you would stick on your desk at home, they did fit under the desk of many offices.  Typically there were built with multiple large circuit boards and their processor was implemented with many MSI (medium scale integration) IC’s and/or straight TTL.  TTL versions of the 1970’s often were designed around the 74181 4-bit ALU, from which 12, 16 or even 32-bit processor architectures could be built from.  DEC, Wang, Data General, Honeywell, HP and many others made such systems.

By the mid-1970’s the semiconductor industry had advanced enough that many of these designs could now be implemented on a few chips, instead of a few boards, so the new race to make IC versions of previous mini-computers began.  DEC implemented their PDP-11 architecture into a set of ICs known as the LSI-11. Other companies (such as GI) also made PDP-11 type IC’s.  HP made custom ICs (such as the nano-processor) for their new computers, Wang did similar as well.

Data General was not to be left out.  Data General was formed in 1968 by ex DEC employees whom tried to convince DEC of the merits of a 16-bit minicomputer.  DEC at the time made the 12-bit PDP-8, but  Edson de Castro, Henry Burkhardt III, and Richard Sogge thought 16-bits was better, and attainable.  They were joined by Herbert Richman of Fairchild Semiconductor (which will become important later on.)  The first minicomputer they made was the NOVA, which was, of course, a 16-bit design and used many MSI’s from Fairchild.  As semiconductor technology improved so did the NOVA line, getting faster, simpler and cheaper, eventually moving to mainly TTL.

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October 11th, 2010 ~ by admin

Soviet Beauties: Processors from behind the Iron Curtain

The Soviet Union’s electronic programs were mainly focused on copying and cloning Western devices.  Either by simple theft, or painstaking reverse engineering.  They made clones of devices such as the Intel 8080, and the AMD 2901 as well as simple TTL.  The Soviets also made many single and multi-chip versions of the venerable DEC PDP-11 computer system.  Many of these have no Western analogs, they were pure creations of the Soviet industry.

Soviet Kvantor 580VM80 - Intel 8080 - Milspec

While Western chips rapidly transitioned into mostly black plastic by the 1980s the Soviets did not.  The 8080 above was made in 1991 though looks like something from the 70’s. Black plastic is cheap, and easy to make, but it isn’t great looking. The Soviets on the other hand made some of the best looking (if not always functioning) processors of the time.

Soviet J-11 Missing the chips

Here is just the substrate (its a non finished example) of a Soviet clone of the DEC J-11 CPU. Not often do you see a brilliant blue processor.

Soviet Angstrem K1801VM1

This is a nice pink ceramic Soviet PDP-11 5MHz CPU. Again this was made in 1991.  Its a form of surface mount package that was used extensively for industrial and military designs.  Just as the PDP-11 was used by the American military throughout the 70’s and 80’s. the Soviets used it (and now Russians) in todays times.

Soviet era CPUs are very interesting to collect.  Each state run factory had their own logo which was typically (but not always) put on the chip. Many part numbers were made by more then one factory. Most chips have a western analog, but not all.  Soviet chips also were ever so slightly different sized then Western ones. The Soviets used a pin spacing of 2.5mm where as the West used 0.1″ (2.54″), rather noticeable on a 40 pin DIP. Reading/translating some of the Cyrillic  based characters can be a chore but really when you get to see things like this…

Electronika J-11 - Image courtesy of iguana_kiev

Can you really complain?