The Web Site to Remember National Semiconductor's Series 32000 Family


NS32016/NS32032 based systems

The Opus board from 1985 is based on the NS32016D-10 CPU with nearly all the peripherals of the family : MMU, FPU and TCU. Main memory is 2 Mbytes of DRAM with partity protection. 1 Mbytes is placed on an add-on board screwed to the main board. The system does not have a boot ROM. Therefore everything is programmed from the host which is obviously a PC. The connector is used for 8-bit ISA slots.

Fig. 1. PC add-on card from Opus.

The photo in Figure 2 shows two boards from Opus in comparison. The upper board is based on the NS32032 CPU. This board uses a large memory expansion board for a total memory size of 4 Mbytes. The lower board is of the same type as in Figure 1 (please note the different series numbers in the upper right corner of the boards). The NS32032 CPU is placed in the upper right corner just below the series number C2301.

The Opus boards were used in CAD systems. For this kind of application they were sold with a large memory array. 144 DRAM chips, each 256-kbit in size, were used for the memory of the NS32032 system. 36 of them are placed on the main board. For the remaining 108 chips an own board was used which equals the size of the main board. Both boards are screwed togehter.

Fig. 2. Two PC add-on cards from Opus: the upper one is based on the NS32032 CPU which is placed under the heatsink.

The photo in Figure 2 is available in higher resolution here .

Since September 2018 some software for the system will be available soon - thanks to Simon, see below. This is great and I will test my board in Richard's hardware.

The application note AN-587 contains a hint to Opus boards on page 4.

In July 2017 Alexander informed me about a surprising discovery. The hardware of the National Semiconductor SYS32/20 Development Package was made by Opus. This way National Semiconductor saved a lot of effort. Whether the hardware of the NS32332 based SYS32/30 is also made by Opus is not known.

Fig. 3. It is obvious that the board of the SYS32/20 is identical to the Opus NS32032 board in Figure 2.

Fig. 4. The 1988 edition of the Series 32000 Microprocessor Data Book describes the content of the SYS32/20 Development Package.

NS32532 based system

Until June 2017 I was believing that the german company Mikron has built an NS32532 based add-on board for the PC. Now I learned from John C. that the board shown in an advertisement from Mikron is an Opus board. Mikron is "only" a systemintegrator.

In 1988 Mikron offered the board with 4 Mbytes of DRAM together with software for ~10,000 which is very high from today's perspective. For this money you got at the end of the 1980's a new VW Golf. A complete system with a Compaq Deskpro 386 PC as a host, a graphic card and a 19" Sony color monitor was offered for ~40,000 . This was the price of a new Porsche!

Fig. 5. The NS32532 based PC add-on board for the 16-bit ISA bus.

The board runs a variety of System V. The two Xilinx FPGAs (XC2018-70, 100 logic cells) are loaded at MSDOS startup. Unix hard disk access was through a helper-program which ran under MSDOS.

Fig. 6. A partially populated daughter card for memory expansion screwed to the CPU board.

The daughter card in Figure 4 has DRAMs on both sides of the PCB. Fully populated it has a capacity of 16 MBytes. Together with the 4 MBytes of the CPU board a system may have 20 MBytes in total. The memory is parity protected.

Fig. 7. A detailed view of the CPU and FPU.

Fig. 8. The board was designed and made in the USA. Please note that the manufacturer of the DRAMs was Motorola.

An Opus card still running in 2018

In September 2018 I got an email from Simon telling me that he has a system with an Opus card. Not very exciting. But one of the next sentences said: "It still works." Wow - this was a true surprise. Until now nobody seems to have something like this. He wrote about the system:

"... The system is an IBM 3270 PC AT/GX. The system was assembled and sold by Valid Logic Systems. The Opus card allowed the IBM PC to boot SYS V Unix and run the Valid GED schematic entry software. The system was loaned by Valid to the company I worked for at the time, LSI Logic. When we were done with it, Valid said they didn't want it back. My boss told me, "Get that thing out of here," so I did. It still works. The Unix still boots, and Valid GED still runs. The monitor weighs 35 Kilos, the base system weighs another 23 Kilos. The Display Attachment Unit is a separate case almost as big and almost as heavy as the base system. The DAU is what we now refer to as a GPU, which is just a card in current desktop systems. Only IBM could build such a monster. At the Vintage Computer Fair in San Jose, CA in 2000, this system took Best in Class (post 1981), Best Presentation (completeness), and Best of Show."

The Opus card inside the PC is identical to the one in Figure 1.

Fig. 9. Below the PC containing the Opus card is the DAU, the Display Attachement Unit.

Fig. 10. The high resolution monitor of the system shows a test picture.

Simon gave me more details about the system:

"Valid specifically chose this hardware configuration and ported their software to it. I believe they also did the Unix port. The 3270 AT GX has what's called an All Points Addressable card that allows the system to write to any point on the screen at 1024x1024 resolution. I do not have any other software that uses this capability except for GED. IBM intended for this system to be used as a graphics terminal connected to a mainframe. In 3270 mode, it was a text-based terminal for the mainframe. In APA mode, it was also a graphics display system. They just let the Opus card replace the mainframe. The system first boots to DOS, then you invoke the Unix boot program and the Opus card takes over the screen. In text mode, Unix looks no different from DOS, just being lines of text that I think are 24x80 characters. This is extremely limiting on such a large monitor! Once GED is invoked, then the 1024x1024 graphics mode is started. I think it only does 4 colors at 1024x1024. The Valid SCALD station had a monochrome green monitor, so GED runs on Opus with green graphics to look the same."

Fig. 11. A detailed view of the output of the Valid GED schematic entry software showing a 4 bit decimal counter.

Starting in 1988 I was sitting in front of a similar system from Daisy and doing schematic entry. Unfortunately I cannot remember any further technical details about Daisy...

It is fascinating to see a system which has done useful work running 30 years later. And still all transistors and bits are in a good shape. I should ask Simon wether he can make a small YouTube video working with the system.

My Opus card is running in 2022

To be honest only the debugger program is currently running. But it is the first step and it required already some help and some good ideas. It will be a long way to go to get Unix running on this machine.

Fig. 12. A view of the experimental set up.

I use an old PC model from Siemens-Nixdorf as the host machine. It's name is PCD-4L. It is based on the 486SL processor running at 33 MHz. The slim design of the computer is nice but it has some drawbacks. First there is not much room inside. And there is no fan. So maybe the Opus card will get hot if the case is closed. I'm not sure if the ventilation slots at the side are sufficient.

Second the power supply of the PCD-4L is weak. It only delivers 5A at 5V. Before the test, I had no idea how much current the Opus card would draw. My guess was around 3A. Therefore I decided to supply the 5V for the Opus card from externally. As you can see in reality it is around 2.5A. The external power supply in Figure 12 is the old power supply for my first National System TITAN1, built in the 1980's.

Fig. 13. A detailed view of the Opus card inside the PC. It is a good feeling to see old hardware working again 😊

Fig. 14. First to note: the tests are PASS! The first program used was "opsash" = Opus Standalone Shell. But nothing useful could be done with it.

The old PC has only a floppy disk drive to transfer data. No USB. So the basic software for the Opus card was transfered serially from TITAN3. For this purpose I had to program the PC in Turbo Pascal which a friend still has on floppy disks - thanks to Manfred!

There is a big challenge with the remaining software for Unix: it is stored on 40 disks not formatted in DOS format. I think an emulation of the floppy drive is a good solution.

The next step is to save the content of the hard disk drive. Then I will try to configure the system. This step is pretty unsafe because I have not the user manual. There are some hints but I'm not sure that this is enough. But if something goes wrong I can restore the saved HDD content.

Does anybody have the Opus532 User Manual? This would be great!

This chapter was last modified on 10 April 2022. Next chapter: PC532