Are there any SC/MP programming manuals for the MK14?

[777xxxx]

or would i just have to use a generic z80 programming manual? i would like a manual which mentions how the vdu is implemented in machine code.

i would like program some kind of monitor for it. i.e. where you can type keys into it an it appears on the screen. has anyone ever attached a qwerty keyboard to the mk14?

[TonyDuell]

Why do you want a Z80 manual for the MK14 which uses the SC/MP processor?

[777xxxx]

Originally Posted by TonyDuell

Why do you want a Z80 manual for the MK14 which uses the SC/MP processor?

sorry i thought it used a z80, ill take another look

[777xxxx]

ok ill rephrase the question.

are there any sc/mp programming manuals for the mk14? which also take a look at the vdu?

[SiriusHardware]

I had better point out that there was actually a rare third party Z80 processor conversion available for the MK14. Someone pointed out a couple of ads for it in a recent thread somewhere. I have no idea how many were sold or if any of them still exist.

777xxxx, there is a follow up book for the MK14 called 'Understanding Microprocessors with the MK14', It is essentially a more detailed version of the manual with a fuller explanation of the instruction set. It is out of print and original copies seem to go for crazy money but if you look hard enough you will find digital copies of it online.

Programming the VDU is actually surprisingly straightforward, it just involves sending data to whatever area of system memory the VDU is set to read from. Is there something you specifically need to know?

[Station X]

Originally Posted by 777xxxx

OK I'll rephrase the question.

Are there any SC/MP programming manuals for the MK14? which also take a look at the VDU?

Thread title updated.

[SiriusHardware]

Appreciated, Graham.

[ortek_service]

There was a previous thread, earlier this year about SC/MP programming books:
https://www.vintage-radio.net/forum/...d.php?t=189202

And a brief overview plus some tools for it here: https://www.sbprojects.net/sbasm/scmp.php

Also a few on this page: https://www.curiousmarc.com/computin...microprocessor
Including documentation on the NS Introkit, which was rather similar to the MK14, being basically the reference-design that the MK14 was based on (and copied the whole Keyboard/Display ROM from)

And bitsavers etc has a few, like: http://www.bitsavers.org/components/...nual_Feb76.pdf

Although these are on the National Semiconductor SC/MP in general, rather than the MK14 VDU - Which I suspect didn't really have any books on, only construction etc. articles

Programming the SC/MP in assembler, may not be too easy - even for experienced 6502 & Z80 assembler programmers, as it seems it wasn't the nicest processor implementation compared to those etc.

[ortek_service]

Originally Posted by SiriusHardware

I had better point out that there was actually a rare third party Z80 processor conversion available for the MK14. Someone pointed out a couple of ads for it in a recent thread somewhere. I have no idea how many were sold or if any of them still exist.
>>
>>

That's interesting, as I don't recall ever seeing this.
I know one of the MK14 designers was keen to use a 'better' processor, and seems had a disagreement with Clive Sinclair over this. And they ended-up leaving to form Acorn, whose System 1 used many similar parts to the MK14 but had moved to the 6502 processor.
Of course Sinclair did then move to the Z80 for the ZX80, ZX81 & Spectrum.

[SiriusHardware]

It's also worth looking through the 'MPUs by Experiment' series which ran from July 1979 to June 1980 in 'Computing Today' magazine.

http://flaxcottage.com/ComputingToday

From July to December 1979 the series concerns itself only with the workings of the SC/MP itself and the experiments are designed to be carried out with an SC/MP plugged into a breadboard. However there is a lot of good info about the SC/MP in that first section of the series.

In the January 1980 issue there is a standalone article about the various kinds of addressing used by SC/MP instructions (page 31) and from this issue on, 'MPUs by Experiment' assumes the SC/MP you've been experimenting with is now in an MK14 - remarkably, Science of Cambridge agreed to supply the kit WITHOUT the CPU to anyone who had been following the series and therefore already had an SC/MP.

The January to June 1980 instalments of 'MPUs by Experiment' are in some ways like an alternative, better manual for the MK14 because they explain a few things which the original manual really doesn't, such as how to display characters / information on the MK14's LED display. Well worth reading through the whole series I think.

[Phil__G]

The recently re-discovered Kemitron book is pretty good, I think its in my stash, hang fire...

[SiriusHardware]

For Owen, this is where the Z80-in-MK14-clothing was briefly discussed (see posts #837 to #839).

https://www.vintage-radio.net/forum/...145663&page=42

[SiriusHardware]

Originally Posted by Phil__G

The recently re-discovered Kemitron book is pretty good:

.... .... ....?

I think there may have been another glitch in the Matrix.

[Phil__G]

yes its near the bottom of the SC/MP page on http://philg.uk (too big to attach here)
"Kemitron guide to SC/MP programming"

[Timbucus]

Maybe I need to do a YouTube series on programming the SC/MP with worked examples on the MK14 and SCRUMPI...

[ortek_service]

Originally Posted by SiriusHardware

For Owen, this is where the Z80-in-MK14-clothing was briefly discussed (see posts #837 to #839).

https://www.vintage-radio.net/forum/...145663&page=42

Thanks for the link back to that in the thread, that I see was added to again quite a bit today - I bet you may now regret not getting a ZX80, going straight to a ZX81, considering how rarer and now more-valuable ZX80's are. And IIRC, you could upgrade the ZX80 with the ZX81 ROM, to add FP-Maths etc. But I suppose if the ZX81 was available by then, there wouldn't be much point buying the ZX80 if not got one already.

Interesting that they also advertised a printer for the MK14 - beating Sinclair's later (ZX-Only) Printer. I've never seen a printer being used on an MK14, and wonder if anyone managed to interface the ZX-Printer to it (Maybe most had moved on from the MK14 by then, as it seems many used ones were being sold not that long after purchase).

I also found some interesting comments on the SC/MP performance compared to later 'NMOS' processors (Although wasn't the 6800 at least earlier) on this page, and hadn't realise it was quite that slow if it had a similar 4MHz clock speed to a Z80A (Only 2.5MHz on ZX80/81):
http://www.computinghistory.org.uk/d...opment-System/


Here are pictures of the Nat Semi SC/MP books /manuals, that whilst don't seem to downloadable from that page, should be available elsewhere: http://www.computinghistory.org.uk/s...Semiconductor/
And searching their website for 'MK14' or 'SC/MP' brings-up pictures of many other interesting publications, that some may not be aware of.

I also spotted from there a SC/MP UV-EPROM burner: programming the 2708 and 2716 Proms project construction article in PCW 1979-Sep magazine at: http://www.computinghistory.org.uk/d...eptember-1979/
With full-magazine / article available at: archive.org/details/PersonalComputerWorld1979-09/page/52/mode/1up?view=theater

[SiriusHardware]

I bet you may now regret not getting a ZX80, going straight to a ZX81, considering how rarer and now more-valuable ZX80's are.

Actually no, there are limits even to my eccentricity - the ZX81 is the machine the ZX80 aspired to be and is more capable and a much nicer looking machine, a design classic which looks great even to this day, especially if you fit 16K of RAM internally so that the good looking lines of the wedge aren't marred by an asymmetric 'brick' hanging off the back.

The monetary value of things only really matters if you actually intend to sell them. I think I've only sold one computer in my entire life, my Amiga 500 which I just didn't find as nice to program as the Atari ST - I sold that while they were still mainstream models. Every other computer I've ever bought I still have.

Some day, when I am about to get carted off into a home, the value of all these things may matter but for now I just enjoy them for what they are.

[Mark1960]

Originally Posted by ortek_service

Interesting that they also advertised a printer for the MK14 - beating Sinclair's later (ZX-Only) Printer. I've never seen a printer being used on an MK14, and wonder if anyone managed to interface the ZX-Printer to it (Maybe most had moved on from the MK14 by then, as it seems many used ones were being sold not that long after purchase).

I did have a dot matrix printer briefly connected to my MK14 back in the day, just to play with the 8154. Unfortunately never had anything much in the memory to print.

[Slothie]

I have a PDF of "Understanding Microprocessors with the Science of Cambridge MK14" but I cant recall where I got it from - The only hit on google is some academic library that requires institutional access - it may have been PM'd to me by someone.. Does anyone else know where I might have got it, ot was it posted in a thread here? It seems to be an extended and improved 209 page version of the MK14 manual with a lot more detail and discussed coding examples.

I would upload it here but I may have promised not to - I know people have sent me other things with that proviso.

[SiriusHardware]

I don't think it is regarded as abandonware, so it's not easy to find. Rodney Dale sadly passed away in 2020. The other author is Ian Williamson, the original 'inventor' of the MK14 - even though his actual design was not the final one adopted by Science Of Cambridge, it sold the concept to them - and we regard him as a Good Guy.

If possible, we should really just ask him if he would mind it being placed in the public domain, or whether he would consider producing it as an E-Book, maybe with some additional extra content. To complicate matters, he himself may not even hold the rights (or the sole rights) to it any more.

I have been looking out for an original copy of it for years but the last one I was chasing rocketed up through the twenties in a matter of seconds and I had a sudden attack of common sense and didn't pursue it further.

Like Slothie, I also have a high quality PDF copy of it, but I honestly can't remember where I found it.