What is the average age on here??

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Coeus
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Re: What is the average age on here??

Postby Coeus » Tue Jan 02, 2018 2:30 pm

sweh wrote:
firthmj wrote:Not sure it is possible to access Stardot from a BBC (go on, prove me wrong!), so I think the answer must be that everyone does!

I wonder how well lynx on a VT-100 would display stardot. Hmm. 'Cos then a Beeb with a good terminal ROM and a modem dialing into an ISP which still supports dialup and gives a unix shell... e.g. Panix in New York.


Interestingly the way the VDU driver works is pretty much like a terminal, though not a VT100. It is as if the BBC micro is a terminal and a computer in the same box. Unix had a system to adapt to the control codes for different terminals. IIRC the database of control codes was termio on SYSV and termcap on BSD. These enabled an application to work with things like "move up a line" and the backend would send the appropriate code to the terminal. Then there was a library, curses, on top of that that let you work with a virtual screen, maintained a copy of what the user's terminal should have on screen, and would send a concise set of differences to bring the user's terminal up to date. A bit like a pre-cursor to MPEG but for text.

So you could write a termcap/termio entry for the BBC VDU driver (unless someone has already done it) and then all that would be needed at the BBC end is a small piece of code to copy RS424 to OSWRCh and OSRDCH to RS423.

Coeus
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Re: What is the average age on here??

Postby Coeus » Tue Jan 02, 2018 3:09 pm

joachim wrote:
jgharston wrote:It always felt that the natural time to have encountered BBCs and become used to programming them was at school in 1982-1985 or so, which would result in you being 45-50 now.

Oh, everyone feels that the way they did it is the only natural way. I encountered BBCs — and wrote my terrible BASIC programs — at infant school in 1982–1985, so I'm not yet 40.


Indeed I am one of the bunch that was at secondary school when the home computer started to become a reality. I started secondary school in 1980 and I think it was during that first year that a maths teacher, who had to be close to retirement, had a XZ80 which we did very simple things on including the guess a number game that uses the binary search algorithm. I don't know if this guy had his ear to ground more than most and could foresee micros taking off or whether it was just a hobby but IIRC this was before the BBC had screened any of their TV programmes on the micro. It was seeing the XZ80 that made me pester my parents for a computer and, by the time I succeeded, the XZ81 was Sinclair's current model. He then upgraded to an Atom and sometime later I upgraded to the BBC Micro.

I had no experience of micros in primary schools. When I was in primary school the height of new technology was a transistorised colour TV with a push-button tuner for watching the schools broadcasts. That had to be live, too, as the primary school had no VCR. We also listened to some radio broadcasts on an old valve radio that had a distribution facility with speakers in each classroom. I am guessing this was probably the 100V line system but I can't be sure.

As for starting to program, I think we did examine the programs behind the simple number games on the XZ80 and Atom but I also remember reading the user guide and trying things out, typing in programs from magazines and working out how they worked etc. Like most things, I think, you don't start off a master but if you're interested enough to persevere you improve.

tautology wrote:I'm just the wrong side of 40; but we saw our first beeb in the last couple of years of primary school (only the one for the whole school) - though this was in deepest, darkest Yorkshire (full of inertia for change: I still remember doing maths exercises in £'s, shillings and pence, even though currency was decimalised years before I was born). My class was one of those that had articles on the Domesday book. (I'm also pretty certain my mother is in one of the pictures.)


Reminds me of the comment supposedly made by the Mayor of New York at the time of Alexander Graham Bell's demonstration of the telephone in response to those who saw no use for it when he was supposed to have said "On the contrary, I can see a time when every town will have one!"

tautology wrote:In secondary school, there was only one room of BBC Bs, with a manky old 380Z at the end. Later the school got more computers: a Master and Torch in the CDT technology and a room of master for business studies, which had, gasp, a modem!


We had a 380Z too. They were older than the BBC micro so it had probably been around for a few years but the casing and keyboard both seemed to be built to withstand lots of abuse so lasted well. Then we got 480Zs at school which seemed like RMs equivalent to the BBC presumably put together after the BBCs started to appear in schools, i.e. their market as, at the time of the BBC's commissioning, they had effectively said "you're having a laugh".

So my choice of the BBC micro wasn't due to being exposed to it at school but because I had to the bug, was looking to upgrade, and the BBC was recommended by the father of a friend of school who worked for ICL.

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sweh
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Re: What is the average age on here??

Postby sweh » Thu Jan 04, 2018 1:18 am

Coeus wrote:Unix had a system to adapt to the control codes for different terminals. IIRC the database of control codes was termio on SYSV and termcap on BSD.

"terminfo", and it's still around...eg on Linux:

Code: Select all

% infocmp | head
#       Reconstructed via infocmp from file: /usr/share/terminfo/s/screen
screen|VT 100/ANSI X3.64 virtual terminal,
        am, km, mir, msgr, xenl,
        colors#8, cols#80, it#8, lines#24, ncv@, pairs#64,
        acsc=++\,\,--..00``aaffgghhiijjkkllmmnnooppqqrrssttuuvvwwxxyyzz{{||}}~~,
        bel=^G, blink=\E[5m, bold=\E[1m, cbt=\E[Z, civis=\E[?25l,
        clear=\E[H\E[J, cnorm=\E[34h\E[?25h, cr=^M,
        csr=\E[%i%p1%d;%p2%dr, cub=\E[%p1%dD, cub1=^H,
        cud=\E[%p1%dB, cud1=^J, cuf=\E[%p1%dC, cuf1=\E[C,
        cup=\E[%i%p1%d;%p2%dH, cuu=\E[%p1%dA, cuu1=\EM,

So you could write a termcap/termio entry for the BBC VDU driver (unless someone has already done it) and then all that would be needed at the BBC end is a small piece of code to copy RS424 to OSWRCh and OSRDCH to RS423.

In the late 80s, the Oxford Clarendon Physics Lab had a room with two High Level Hardware Orion computers, which ran a BSD4.2 based OS. The terminals were all BBC Micros running UTE5 ("Unix Terminal Emulator", written by Dr Clive Rodgers) from ROM. From memory this ROM was pretty dumb and just passed through escape sequences unchanged. So, yes, the termcap entry on those machines did, pretty much, just expose the relevant VDU calls.

(There was also a method of escaping from the ROM into BASIC and having input connected to the serial port; I forget how... but one clever person used this to create a small file loader app and we could download games like MrEE from files stored on the Unix machine :-))
Rgds
Stephen

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MikeKee
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Re: What is the average age on here??

Postby MikeKee » Fri Jan 05, 2018 6:02 pm

I'm 55.

I was a Primary School teacher from 1987-1998 so was around when Beebs were being used in the classroom and then the Archimedes coming in.

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Re: What is the average age on here??

Postby crj » Sat Jan 06, 2018 4:28 am

sweh wrote:
Coeus wrote:Unix had a system to adapt to the control codes for different terminals. IIRC the database of control codes was termio on SYSV and termcap on BSD.

"terminfo", and it's still around...eg on Linux:


From the RISCiX /usr/share/lib/termcap :

Code: Select all

bz|bt100|Master 128 ANSI mode - see also sx:\
        :cr=^M:do=^J:nl=^J:bl=^G:co#80:li#25:cl=50\E[;H\E[2J:\
        :le=^H:bs:am:cm=5\E[%i%d;%dH:nd=2\E[C:up=2\E[A:\
        :ce=3\E[K:cd=50\E[J:\
        :rf=/usr/lib/tabset/vt100:\
        :so=\EPVDU17,129,17,0\E\134:\
        :se=\EPVDU17,128,17,1\E\134:\
        :to=\EPVDU17,129,17,0\E\134:\
        :te=\EPVDU17,128,17,1\E\134:\
        :kl=\E[D:kr=\E[C:kd=\E[B:ku=\E[A:kh=\E[;H:\
        :is=\E[>0l:ta=^I:sr=\EM:vt#3:

bbcvdu80x32|acorn0|BBC VDU Driver Mode 0:\
        :li#32:co#80:am:cl=^L:bs:cm=^_%r%.%.:up=^K:ho=^^:bl=^G:bw:\
        :ce=^W^H^E^F\200\200\200\200\200\200:\
        :so=^W^Q^E\200\200\200\200\200\200\200:\
        :se=^W^Q^E\200\200\200\200\200\200\200:\
        :sb=^W^G^A^B\200\200\200\200\200\200:\
        :sf=^W^G^A^C\200\200\200\200\200\200:\
        :is=^C^F^D^O^V\200:
bbcvdu|acorn12|Acorn VDU Driver Mode 12:\
        :li#32:co#80:am:cl=^L:bs:cm=^_%r%.%.:up=^K:ho=^^:bl=^G:bw:\
        :ce=^W^H^E^F\200\200\200\200\200\200:\
        :so=^Q^O:\
        :se=^Q^G:\
        :sb=^W^G^A^B\200\200\200\200\200\200:\
        :sf=^W^G^A^C\200\200\200\200\200\200:\
        :is=^C^F^D^O^V^L:


Those might or might not be useful to people.

My own recollection is that bbcvdu80x32 runs into significant difficulty with the Beeb's tendency to scroll when you put a character in the bottom right corner of the screen, rather than waiting for the first character of the next line. Command-line telnet on an Archimedes benefited considerably from a judicious VDU23,16,1,254| , and that probably works on the Master as well. But frankly it was still flaky enough that you'd be foolish not to use !vt220 instead.

Coeus
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Re: What is the average age on here??

Postby Coeus » Sat Jan 06, 2018 1:39 pm

crj wrote:
sweh wrote:
Coeus wrote:Unix had a system to adapt to the control codes for different terminals. IIRC the database of control codes was termio on SYSV and termcap on BSD.

"terminfo", and it's still around...eg on Linux:


Indeed, writing the in the past tense really meant this was something I used in programs at one point before GUIs and then web-based applications became more common, not that the feature had been removed.

crj wrote:My own recollection is that bbcvdu80x32 runs into significant difficulty with the Beeb's tendency to scroll when you put a character in the bottom right corner of the screen, rather than waiting for the first character of the next line. Command-line telnet on an Archimedes benefited considerably from a judicious VDU23,16,1,254| , and that probably works on the Master as well. But frankly it was still flaky enough that you'd be foolish not to use !vt220 instead.


Interesting.

I' also interested to note the 200 (octal) bytes in the BBC VDU sequences. I assume these are actually intended to act as NULs so the entry relies on something stripping the eighth bit.

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Re: What is the average age on here??

Postby crj » Sat Jan 06, 2018 8:06 pm

Well, one of them is doing an actual honest-to-goodness MODE 128. (-8
The others are unused VDU23 parameters, which are defined(?) to be ignored rather than must-be-zero. I'm not sure why they used \200 when they could have used something simpler like 'x'. I'm inferring that termcap treats \0 specially...

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sweh
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Re: What is the average age on here??

Postby sweh » Sat Jan 06, 2018 9:43 pm

Strings in C are just a pointer to characters ("char *") terminated by NUL; they're not counted. So a string "hello\0there\0everyone" will be stored as "hello\0there\everyone\0" but when you try to read it then you'll just get back "hello".

From my old SunOS4 manpage for termcap.5

Code: Select all

       If it is necessary to place a NUL character in a string  capability  it
       must  be  encoded  as \200.  (The routines that deal with termcap use C
       strings and strip the high bits of the output very late, so that a \200
       comes out as a \000 would.)
Rgds
Stephen

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Re: What is the average age on here??

Postby crj » Sun Jan 07, 2018 1:52 am

Hmm. That would pre-date 8-bit-transparent links to terminals, I suspect. (-8

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Re: What is the average age on here??

Postby David1664 » Mon Jan 08, 2018 9:23 am

42.

(About the same number of times I've watched Star Wars: A New Hope)