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muta...@gmail.com

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Feb 16, 2022, 4:40:45 AMFeb 16
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What is the worst people had to do, presumably on
early computers, to get a program/OS loaded? Did
you have to enter a program one byte at a time with
a set of 8 switches? Did you have another set of
16 switches for the address in memory, and then
press an "enter" switch?

Were there lights to see what was already at a
particular address? And after all that effort, what
was the mechanism to save the entered data to
permanent storage, and load it again?

Thanks. Paul.

Luca Baker

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Feb 16, 2022, 5:02:14 AMFeb 16
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they did a thing.

s_dub...@yahoo.com

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Feb 16, 2022, 9:57:27 AMFeb 16
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As to the last sentence..
o there was paper tape, see ASR 33 .. https://en.wikipedia.org/wiki/Teletype_Model_33 .. some thing I never used.
o there was audio tape, i.e. reel to reel or cassette, ref https://en.wikipedia.org/wiki/ZX_Spectrum ..
Which I'd used, a micro-cassette connected to a ZX 81 and a portable B&W TV with a 6" screen for output & BASIC in ROM.
-- which brings up the point of having BASIC in ROM and using BASIC peek & poke as a program loading technique for a binary program. The IBM 5150 has BASIC in ROM, and a cassette interface circuitry.
https://en.wikipedia.org/wiki/IBM_Personal_Computer

As to the prior sentences..
This Altair 8800 article..
https://en.wikipedia.org/wiki/Altair_8800
..has pictures of the front panel, which seems is self-explanatory as to the switches and selections.
Very early on, the front panel was the way to enter the Loader Program, byte by byte, address by value, into memory to bootstrap a program (say an interpreter like BASIC or an OS. Later, this Loader was placed into ROM to automate 'load and go'.

hth,

Steve


> Thanks. Paul.

Johann 'Myrkraverk' Oskarsson

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Feb 16, 2022, 10:26:16 AMFeb 16
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On 2/16/2022 9:40 AM, muta...@gmail.com wrote:
> What is the worst people had to do, presumably on
> early computers, to get a program/OS loaded? Did
> you have to enter a program one byte at a time with
> a set of 8 switches? Did you have another set of
> 16 switches for the address in memory, and then
> press an "enter" switch?

I wasn't there, so I can't speak from personal experience,
but I believe machines programmable with punch cards could
be bootstrapped by punching in the object code -- sometimes
by hand -- and then feed the cards to the 'puter. Of course
that means some sort of loader/executor was already there,
either in hardware, or entered through some sort of front panel.

> Were there lights to see what was already at a
> particular address? And after all that effort, what
> was the mechanism to save the entered data to
> permanent storage, and load it again?

Some people could read the drum memory, to see what was going on,
by eyeball.

--
Johann | email: invalid -> com | www.myrkraverk.com/blog/
I'm not from the Internet, I just work there. | twitter: @myrkraverk

Kerr-Mudd, John

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Feb 16, 2022, 11:26:54 AMFeb 16
to
On Wed, 16 Feb 2022 15:26:11 +0000
Johann 'Myrkraverk' Oskarsson <joh...@myrkraverk.invalid> wrote:

> On 2/16/2022 9:40 AM, muta...@gmail.com wrote:
> > What is the worst people had to do, presumably on
> > early computers, to get a program/OS loaded? Did
> > you have to enter a program one byte at a time with
> > a set of 8 switches? Did you have another set of
> > 16 switches for the address in memory, and then
> > press an "enter" switch?
>
> I wasn't there, so I can't speak from personal experience,
> but I believe machines programmable with punch cards could
> be bootstrapped by punching in the object code -- sometimes
> by hand -- and then feed the cards to the 'puter. Of course
> that means some sort of loader/executor was already there,
> either in hardware, or entered through some sort of front panel.
>
> > Were there lights to see what was already at a
> > particular address? And after all that effort, what
> > was the mechanism to save the entered data to
> > permanent storage, and load it again?
>
> Some people could read the drum memory, to see what was going on,
> by eyeball.
>
news:alt.folkore.computers
is the place to ask; xposted

--
Bah, and indeed Humbug.

Scott Lurndal

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Feb 16, 2022, 12:02:11 PMFeb 16
to
Johann 'Myrkraverk' Oskarsson <joh...@myrkraverk.invalid> writes:
>On 2/16/2022 9:40 AM, muta...@gmail.com wrote:
>> What is the worst people had to do, presumably on
>> early computers, to get a program/OS loaded? Did
>> you have to enter a program one byte at a time with
>> a set of 8 switches? Did you have another set of
>> 16 switches for the address in memory, and then
>> press an "enter" switch?
>
>I wasn't there, so I can't speak from personal experience,
>but I believe machines programmable with punch cards could
>be bootstrapped by punching in the object code -- sometimes
>by hand -- and then feed the cards to the 'puter. Of course
>that means some sort of loader/executor was already there,
>either in hardware, or entered through some sort of front panel.

Indeed. My first professional job was to replace a punched-card
bootstrap with a floppy-based bootstrap on a Burroughs mainframe.

There were various forms of binary 80- (and 96-) column cards
used by various manufacturers - Some Burroughs machines
punched three bytes over two 12-row columns, other used
6-bit codes one per column (the PDP-8/12 also used 6-bit
codes which were half of a 12-bit word).

The Burroughs machines also allowed programming the processor
via a maintenance panel (hardware on the B3500(1966) with switches
and nixie tubes, software on the B4900(1979) and successors using a
8085-based maintenance processor to access scan chains on the
host).

muta...@gmail.com

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Feb 16, 2022, 5:54:20 PMFeb 16
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On Thursday, February 17, 2022 at 1:57:27 AM UTC+11, s_dub...@yahoo.com wrote:

> This Altair 8800 article..

Thanks for that article. That filled in a lot of gaps in
my knowledge.

BFN. Paul.

wolfgang kern

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Feb 16, 2022, 7:02:37 PMFeb 16
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Yes, all of it (switches,lamps and buttons) on my NOVA II,
8KB magnetic core memory needed 30 Ampere to write to it,
but it also had an impressive 100KB 3M cassette drive.
__
wolfgang
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