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-   -   INS8073 - What I wanted, but never got. (https://www.vintage-radio.net/forum/showthread.php?t=170994)

Buzby123 13th Sep 2020 1:48 pm

INS8073 - What I wanted, but never got.
 
1 Attachment(s)
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

SiriusHardware 14th Sep 2020 6:08 pm

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

Mark1960 14th Sep 2020 8:09 pm

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.

SiriusHardware 14th Sep 2020 8:21 pm

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?

Mark1960 14th Sep 2020 9:19 pm

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.

SiriusHardware 14th Sep 2020 9:27 pm

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.

Timbucus 14th Sep 2020 9:48 pm

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

Originally Posted by Buzby123 (Post 1288891)
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

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...

Mark1960 16th Sep 2020 5:20 pm

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.

Mark1960 17th Sep 2020 4:59 pm

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.

Mark1960 7th Oct 2020 2:20 am

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.

Phil__G 7th Oct 2020 11:19 am

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?

Mark1960 13th Oct 2020 8:48 pm

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

Timbucus 14th Oct 2020 12:13 am

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.

Buzby123 14th Oct 2020 12:48 am

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.

Timbucus 14th Oct 2020 12:58 am

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.

Mark1960 14th Oct 2020 2:07 am

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

Originally Posted by Phil__G (Post 1296737)
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?

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.

wallaceowen 17th Mar 2021 9:48 pm

Re: INS8073 - What I wanted, but never got.
 
1 Attachment(s)
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)

Buzby123 18th Mar 2021 2:19 pm

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

Mark1960 18th Mar 2021 6:04 pm

Re: INS8073 - What I wanted, but never got.
 
1 Attachment(s)
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.

Timbucus 18th Mar 2021 9:29 pm

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.


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