INS8073 - What I wanted, but never got.
 

Clearing out old paperwork, found this.

I wanted one, but at £25.60 + VAT it was not to be.

Did anyone here ever get to use one ?.

Cheers,

Buzby

Re: INS8073 - What I wanted, but never got.
 

Looks interesting... there is a digital version of that datasheet here, for anyone who wants a closer look.

http://www.classiccmp.org/cini/pdf/N..._DataSheet.pdf

The above link is dead.

See here:-

https://www.vintage-radio.net/forum/...d.php?t=194288

Re: INS8073 - What I wanted, but never got.
 

I was looking for the ins8070, but it doesn’t seem to be available anywhere. I saw that ins8073 is available, though very expensive and uncertain if they were genuine. Unfortunately it doesn’t look like the internal rom of the ins8073 can be disabled to allow use with external programs except possibly by calling routines from basic.

Re: INS8073 - What I wanted, but never got.
 

I imagine the internal ROM of the 8073 is where the BASIC interpreter resides, so if you managed to buy one, I don't know why you'd want to disable that feature.

The interpreter contained in internal ROM is surely used in conjunction with either external ROM or external RAM, either of which can hold BASIC programs. Or have I misunderstood that?

Re: INS8073 - What I wanted, but never got.
 

I was more interested in the ins8070 and the additional instructions compared to the ins8060. The ins8070 includes stack operations and also multiply and divide, so it would be interesting to see if this made programming any easier and then if it made the ins8070 more competitive against the 6502 or z80.

It has a similar bus interface to the ins8060, removing cont, ads, si and sout to allow a full 16 bit address bus, instead of multiplexing the top 4 bits of address with the data bus. It should have similar multiprocessor option as the ins8060, but not sure if that could be used from the onboard basic of the ins8073.

Re: INS8073 - What I wanted, but never got.
 

I think Buzby's interest was really due to the inbuilt Tiny Basic but I see now that you were really looking for an improved but freely programmable SC/MP. I confess the lack of a stack and CALL / RET instructions is probably the thing I like least about the INS8060.

Re: INS8073 - What I wanted, but never got.
 

I spotted that when researching NIBL - I notice that the only one listed at the moment is now £27.38 but, with £44 postage - so still significantly cheaper than your £200 roughly then.

This was a massive reduction in cost in a few years as the NIBL proms (set of 8) are an eye watering £147.60! in 1978

https://nosher.net/archives/computer...ay_1978-06_002

That is around £800 today...

Re: INS8073 - What I wanted, but never got.
 

I discovered a local supplier here that has the ins8073 at $14 each, but these are listed as clean pulls. I’ve ordered a couple to play with and will report back in a few weeks when I get chance to test them.

It looks like there are a couple of options to run machine code from reset. Either changing the character output vector and not returning or a simple basic program to link to machine code routine.

I’m not quite clear if its possible to preload ram with a basic program before allowing the ins8073 to run. From the spec it seems it can determine if the memory is ram or rom and it can run basic programs from rom.

The internal memory access seems to not generate bus requests so will be interesting to see how this might make a multiprocessor more efficient. There might be quite a few useful routines in the internal rom.

Re: INS8073 - What I wanted, but never got.
 

While searching for documents on the ins8073 i found this site.
https://8073sbc.wordpress.com/2019/1...uter-contents/

Quite an interesting read, but also contains many links to documents that I didn’t find when using a search engine.

Re: INS8073 - What I wanted, but never got.
 

I have the INS8073N kind of working. Point to point wiring on proto board with a 74LS04 to buffer the F1, F1 and SA to an Ft232 serial interface. Using a 74LS682 and 74ACT253 to decode /Mreq and /Iorq to drive a z80 64k ram board.

Ram is battery backed, so setting 0xFD00 to 0x80 using a z80 board to select 4800 baud. 0xFD00 seems to be getting corrupted so it takes a few attempts to get the INS8073N up and running.

I also have a problem with some memory areas not working with the INS8073N, but using NEW 8192*3 is working.

I’ll take another look at the way I’m generating /Mreq, it’s currently generated from /WDS and /RDS, but maybe should only be from the /iopage decoded at 0xE0xx.

Re: INS8073 - What I wanted, but never got.
 

Just a suggestion re the corruption Mark, you could try a schottky across the memory board supply, band to +5, prevent negative connect/disconnect spikes?

Re: INS8073 - What I wanted, but never got.
 

Looking through some of the documentation for the INS807x series I found a reference to the INS8075, which seems to be similar to INS8073 but with a 4K version of tiny basic instead of the 2.5K of the INS8073. So far I’ve not been able to find any documentation on the INS8075.

I did find this page about the MC 6400 which as far as I can tell seems to be the only commercial product using the INS8073. It’s in german but just about possible to read with my very poor understanding of german.
http://norbert.old.no/extra/extra3.html

Re: INS8073 - What I wanted, but never got.
 

Interesting find. For anyone with less strong German like me if you drop the URL into translate.google.co.uk you can click on the link in the translated section and browse it to read in any language... it seems quite good with German to English.

Re: INS8073 - What I wanted, but never got.
 

Regarding Google Translate, I use Firefox, and a right-click gives a menu with a 'translate page' entry. I'm not sure if this is inherent, or if it's an add-on.

This opens the current page in a new tab, and translates it to English.

That German page translates nicely, and describes the 6400 kit well. It does not look like the 6400 used an 8073, just an 8070. Even the index listing of the handbook only mentions machine code, no mention of BASIC.

Re: INS8073 - What I wanted, but never got.
 

It was not on my copy but, It was an addon from Juan Escobar from the AddOn's - installed, very handy - every day is a learning experience - thanks Buzby123

Yes there is a short section at the bottom about the 8073 being an expansion later on the specific model he obtained I think.

Re: INS8073 - What I wanted, but never got.
 

Removing one of the 8K ram chips from 4000 to 5FFF seems to have solved the issue with corruption of FD00. I’m suspecting the search for the extent of ram for the corruption.

Also discovered I have too many inverters between F2 out and RTS output, I used two as I didn’t realise it should be inverted.

Re: INS8073 - What I wanted, but never got.
 

Greetings from San Diego, California.

While clearing out my garage I came across an old, ignored parts drawer box.

In one of the drawers I discovered four INS8073s I'd purchased back when they were new. These were the last four from a tube I bought from my distributor.

If anyone is interested I would like to give them away to a worthy home, as I know I'll never get around to making use of them.

Basically the only reason I joined was: When I did a search for INS8073 to look for docs, etc. I found these semi-recent posts.

I hope this doesn't break any rules. I just have a hard time throwing things away that might help someone else, so I ask.


// Wally Owen (user wallaceowen).

(by the way, the 24-pin chip is a Harris Semi Manchester encoder/decoder)

Re: INS8073 - What I wanted, but never got.
 

Hi Wally,

Welcome to the forum !.

I wanted one of these 40 years ago, and I'd still like one now.

I've sent you a PM.

Cheers,

Buzby

Re: INS8073 - What I wanted, but never got.
 

Adding the schematic that I created when testing the samples from a local supplier. Maybe a useful reference for the interface to a USB serial adapter. I found the hardware flow control does not work correctly but I think this is down to the USB serial adapter as that is quite a common problem, though easily solved by adding a delay between characters sent by the terminal emulator.

The memory interface that I used was to connect to an RC2014 bus which is z80 based so I used 74LS682 to decode a 256 byte memory mapped IO.

I used battery backed RAM for memory and store the reset configuration in ram using a z80 with toggle switches, then swap back to the 8073 to run NIBL at 4800 baud.

After finding out that the 8060 can run at 8MHz I've been thinking of testing the 8073 at 8MHz, which would give 9600 Baud, but I didn't get round to trying it yet.

Re: INS8073 - What I wanted, but never got.
 

Hello Wally from San Diego - welcome to the forum - you may wish to keep one, this forum seems to have an effect on people who were getting rid of something... :)

Well being an avid follower of all these things I would love to get one of them! Maybe if there are a few UK requests we could simplify your life and post on from a central point.

Re: INS8073 - What I wanted, but never got.
 

Hello Wally.

I am surely interested too. Impossible to buy one until now. I did experiment a lot with its older brother INS8060 (SC/MP) but surely want to make a single board computer with this one. Would you consider shipping one of those to the Netherlands too?

Re: INS8073 - What I wanted, but never got.
 

I posted the four INS8073 chips to Buzby123, so they're all on your side of the Atlantic now, and he said he'd share them with others. He covered the p/p and customs fees.

Re: INS8073 - What I wanted, but never got.
 

There are lots of SC/MP enthusiasts and projects on this board so welcome! I am sure Buzby123 will be in contact with you - as you are a new user until you have a few posts you may find delays as you await approval and i think PM's are restricted as well. Maybe you could outline what you fancy building with this chip...

Re: INS8073 - What I wanted, but never got.
 

Hello Tim, Jeff was so kind to send me one so when it arrives I will see how I can make it to a nice SBC with terminal access. Of course all in wire wrap, best technique if your plans are not sure yet. I will keep you informed.

Re: INS8073 - What I wanted, but never got.
 

For those following along I intend to build this single board computer....

https://www.facebook.com/groups/1233...9238310451124/

based on one in a French magazine linked from the above post.

Re: INS8073 - What I wanted, but never got.
 

Could we get a direct link that doesn’t require facebook please?

Re: INS8073 - What I wanted, but never got.
 

I also don't 'do' Social Media at all but I'm resigned to the fact that I am one of the odd people out, so if something's only viewable on Facebook I just won't see it.

Re: INS8073 - What I wanted, but never got.
 

Apologies - Only just realised it was a closed group anyway so you can't see it without joining the actual group - sometimes public groups you can see without joining FB...

Anyway it links to this site: https://www.hb9afo.ch if you go to Articles and look down to 1982 there is Micro-Von in Megahertz magazine.

On the group George Rudolf Mezzomo has created a free to use for non profit modern SBC adaption. here is a photo - I hope to get a small number made if anyone is interested in an at cost one.

The PDF is one I found somewhere for an alternate I cannot find the source.

Attachment 232198Attachment 232199

Re: INS8073 - What I wanted, but never got.
 

Thanks Tim - I will be an interested observer only on this one, I'm really going to have to start running away from microprocessor projects rather than running towards them otherwise I'll get nothing else done. I'll live vicariously through you instead.

Re: INS8073 - What I wanted, but never got.
 

Hi Tim,

Has your 8073 arrived yet ?.

Regarding the build, when I get back going again I don't think I'll use that PCB you posted. I want to include an 8255 or similar to give some I/O. It will be good excuse to brush up on my PCB design skills !

Cheers,

Buzby

Re: INS8073 - What I wanted, but never got.
 

Buzby,

Yes indeed it has arrive safe and sound - thank you for sorting that and for Mr Wallace providing them - it has joined the project queue of jobs which seems to get longer each day.

Tim

Re: INS8073 - What I wanted, but never got.
 

There isn’t much that needs to be connected to get a basic system running.

I created a component in eagle 7.6 if its any use to anyone, but so far only assembled with 8154 using point to point wiring and zif connectors. Eagle 7.6 was prior to requiring registration so I haven’t upgraded.

I was wondering if these might work well with multiprocessor, mk14 vdu, or ortonview, as they don’t access bus for internal rom and ram cycles, but I’m still busy and trying to get a digital cassette interface working.

Re: INS8073 - What I wanted, but never got.
 

Last week I received one of the INS8073 micorprocessors, kindly shared by Wally (thank you again) I picked my schematic today, it was illustrated in the Dutch magazine Radio Bulletin of July 1984.
If people want a translation, please let me know and I will make one. It is a very simple schematic and I want to start with the proposed 2K static RAM, using the 6116. I will expand to 64K when all works well. The board will be made in wire wrap and the connection to terminal will be simplified, hoping it will work the same way the SC/MP is communicating (SENSEB - FL0)

Re: INS8073 - What I wanted, but never got.
 

That is a simple circuit !.

Does the article explain why there are pullups on only some of the data lines ?

Re: INS8073 - What I wanted, but never got.
 

D1, D2 and D7 should be pulled high to select 110 Baud. I will experiment with this as the schematic was made with a slow terminal in mind.
The datasheet page 3 says: "Note from the above table that if only the 110 baud rate is required, pullup resistors on data lines D1, D2 and D7 represent the only external hardware required to select this baud rate."
In our NIBL programs for INS8060 we could change the timing constants by changing some addresses in the start of the programm (on the EPROM). As this NIBL is in ROM, baudrate has to be chosen by external hardware.

Re: INS8073 - What I wanted, but never got.
 

The serial interface could be simplified if you do not want to use a current loop and just hook up a TTL to USB serial connector.

Re: INS8073 - What I wanted, but never got.
 

Remember that the usb to ttl converters don’t always (almost never) support 110 baud.

As you have an ‘138 for address decoding you could add a couple of diodes to pull the data lines to select 4800 baud. You might need to swap the address and enable lines on the ‘138 to allow decoding for both ram and the baud rate selection.

Re: INS8073 - What I wanted, but never got.
 

Also you don’t need the ‘14 for the clock, just use the internal oscillator. The 8070 spec gives the schematic and component values, though I’m not sure if your 8073 has the earlier or later resistor required.

Re: INS8073 - What I wanted, but never got.
 

Thank you all for the extra information. I want to keep the schematic as simple as possible. The strength of this device is it's autonomy so I want to use it
how it was meant to be used.
Pulling up only D7 should give me a baudrate of 4800 and I think most USB to TTL converters can cope with that. In worst case I use a real RS232 circuit using the max232 and some capacitors.

Re: INS8073 - What I wanted, but never got.
 

D1 and D2 might need to be pulled down and not just left floating, but I guess you could try without the pull ups and see what happens.

Re: INS8073 - What I wanted, but never got.
 

All Components are mounted, the wire wrapping can start. I populated the sockets just to show how it will look and of course I will take the IC's out when wiring the back. This is the schematic that I showed in my first post (Radio Bulletin). Perhaps I don't need the 4Mhz Crystal but in the middle I reserved a socket to push it in, should I need (or want) it.

Re: INS8073 - What I wanted, but never got.
 

Wow fast progress - I like the idea of doing it with a wirewrap - I have one 40 pin socket so may explore doing the same.

Re: INS8073 - What I wanted, but never got.
 

Yes, Wirewrap was quite common in the days of Eurocard prototyping, these separate square pads boards being designed for it, and I still often used to type with contnous ground plane grid on the top.
Quite reminiscent of the original NS PMOS ISP-8A/500 (SC/MP-I) Introkit Keyboard + Display interface teleprinter-alternative, where this kit came with instructions on how to assemble it with wire-wrapping.

Quite novel to put all the passives on headers, in case they altering.
I've always fitted these with leads adjacent to where they connected, and bent lead onto adjacent pad, but not as neat and makes changing things more difficult.

Re: INS8073 - What I wanted, but never got.
 

From this afternoon, the INS8073 is alive!

I will post the final schematic.
I could not get the clock pulsing from the schematic that was drawn in my first post. After modification with the same clock I used for the INS8060, all worked fine. This means I only need one inverter from the 74LS14 (TTY after F1)
Mark you were right about the D1, D2, I had to pull them to ground to get 4800 baud at start up.
Tiny basic is a bit different from NIBBLE so I have to find my way programming it but all seem to work as described in the manual.
I enclose some pictures so you can see the result of my weekend's work.

Re: INS8073 - What I wanted, but never got.
 

Well done and so neatly constructed it goes well with a device from then. I had not really looked at the BASIC I just assumed it was the same as NIBL!

Re: INS8073 - What I wanted, but never got.
 

Bravo !.

Re: INS8073 - What I wanted, but never got.
 

NIBL and Tiny basic are very similar. One difference i found on start up was that you have to tell Tiny basic where you want to store the program by typing "NEW #1000 " followed by NEW. This way you can store several programs at different memory locations. In NIBL you can run several programs in different pages. If you don't type the NEW command, you get an error after every line you type.
The fluent overflow from basic to machine code is the same. LINK, TOP, STAT the use of @ to choose an 16-bit address are all the same. I miss Karen's "page 2" though, page 2 with it's simple assembler and abbility to show blocks of memory brings you so much closer to machine language without really leaving BASIC.
One other thing that is different: the INS8073 becomes a bit warmer than the INS8060.

Re: INS8073 - What I wanted, but never got.
 

I didn’t notice my INS8073 running warmer than the INS8060.

Did you leave any inputs floating?

I wonder if yours is an NMOS version of the INS8073, mine has date code 8352, and there is a note in the feb81 data sheet that they are now shipping XMOS.