On 06/08/2023 09:42, Jan Panteltje wrote:
> On a sunny day (Sun, 6 Aug 2023 08:51:31 +0100) it happened The Natural
> Philosopher <tnp@invalid.invalid> wrote in <uanje4$25fvd$1@dont-email.me>:
>
>> On 06/08/2023 05:01, 23k.304 wrote:
>>> On 8/5/23 4:01 AM, The Natural Philosopher wrote:
>>>> On 05/08/2023 05:20, 23k.304 wrote:
>>>>> On 8/4/23 4:58 AM, The Natural Philosopher wrote:
>>>>>> On 04/08/2023 07:03, 23k.304 wrote:
>>>>>>> Still have the old IBM Technical Reference Manual.
>>>>>>>    All that stuff was meticulously documented.
>>>>>>
>>>>>> I gave that away sometime in the late 80s.
>>>>>
>>>>>    I consider it to be a "valuable artifact" :-)
>>>>>
>>>>>    At minimum, it showed how serious and deep they'd
>>>>>    go with the early PCs. That's when programming was
>>>>>    still painfully "real". Mostly you could not buy
>>>>>    what you needed - so you had to make it yourself.
>>>>>
>>>>>    And I *did* find many uses for that info.
>>>> Oh, so did I. I was assembly programming 8086s then - writing BIOS
>>>> extensions or complete BIOSES for them,
>>>>
>>>>> https://www.youtube.com/watch?v=WUVZbBBHrI4
>>>
>>>   Shoulda gone with the Frenchies, they LOVE nuke !  :-)
>>>
>>>   Never went as far as a full BIOS. Leveraging what IS,
>>>   what's commercial, what's widespread and "standard"
>>>   was generally my approach. In the time it takes to
>>>   write a BIOS, esp solo, I could do ten times the stuff
>>>   with my approach.
>>>
>>>   But to each ...
>>>
>> I was being paid to get custom designed hardware to perform.
>> This minicomputer company wanted an 8088 board to control the other
>> boards in their super fault tolerant computer. So there it was, a bare
>> 8088 board with PROm and some RAM and they wanted to be able to load
>> code from an 8" floppy, and drive a serial monitor, oh and while you are
>> at it, write us a full C library in ROM and an FORTH interpreter -
>> here's the source code in a 150 page scan of some magazine article.
>>
>> That's 6 months of my life I wont get back. They were going to write a
>> multitasking basic operating system on top of that but my contract
>> expired before they got that far.
>>
>>
>>>
>>>> Or interfacing with special hardware people had built that needed
>>>> drivers written.
>>>> But that line of business dried up, so I ended up doing yet another
>>>> career shift into running IT businesses.
>>>
>>>   Once you COULD buy lots of neat stuff off the shelf,
>>>   then yea, a focus shift made sense. Never tried/wanted
>>>   to RUN businesses though - massive pain in the ass and
>>>   biz WAY too often winds up in the shitter.
>>>
>> No option. No one wanted a 43 year old self taught programmer. They
>> wanted bushy tailed youngsters who wrote C++ and had been schooled in
>> all sorts of theoretical shit that enabled them to justify writing
>> shitty bug filled code.
>>
>> When no one is offering jobs, it sensible to invent your own. It
>> started as technical support, but as it became apparent that the other
>> people in the business hadn't a clue how to actually run a business -
>> accounts, operations, technical support and so on, I ended up running
>> more than half the employees.
>>
>> I needed a job, and that was the only way I could guarantee the business
>> didn't fall to pieces with incompetence.
>>
>> Well it fell to pieces with ego, so a couple of us started another one,
>> and I ended up running most of that too.
>> When I had enough cash accumulated, and my co directors wife started
>> trashing the business, we sold it and I gave up work altogether.
>>
>> I'd frankly had enough. So I retired at 50.
>
>
> I had a TV repair shop for years during the late seventies and early eighties.
> Worked for the national TV network here before that
> and before that designed electronics for the among other things army and navy.
> After the repair shop did many things, often via agencies.
> Electronics is everywhere so gained knowledge of a lot of fields
> from missiles to medical (worked in a university hospital too) and space and physics (accelerator).
>
> Curiosity is likely what drives me.
>
>
>
>
>
>>
>>>   Was still programming in solder into maybe half a
>>>   dozen years ago - stuff you couldn't, or wouldn't,
>>>   buy off the shelf. However that stuff was for
>>>   microcontrollers, not real CPUs.
>>
>> I still solder stuff together. And I will be for this current Pi project
>> too. I need an internal mains power supply for the server - to hell with
>> USB wall warts - and I need a special bit of kit that turns on after up
>> to an hours delay, boots a pico and runs it until the PICO has done its
>> stuff and issues a shutdown signal on a GPIO pin, and puts the whole
>> thing to sleep at a couple of µA or so for up to an hour, to get a
>> decent battery life.
>>
>> Oddly enough the best solution to that looks to be not some specialised
>> complex chip, but an old school simple 4000 series CMOS Schmitt
>> trigger, some Rs and Cs, and three boring old school transistors. 1970s
>> technology in fact.
>>
>> In quiescent state, the only current draw will be leakage current on the
>> transistors charge current on the timing capacitor and the quiescent
>> current of the CMOS Schmitt, which at 4.5v is less than a µA...the best
>> I could do with clever chips like a CMOS 555 timer was around 16µA.
>>
>> If it works I might get some PCBS made up for that. Lots of people might
>> want a PICO for use as a remote sensor on batteries on an 'occasional'
>> basis.
>>
>> So old school it is. I am hoping for at least a years battery life on
>> the oil tank sensor. Even if that means only monitoring the level once
>> an hour or less.
>
> I have done a fluid level sensor with just a 4040 counter and an echo system
> 555 timer, sending a beep down to the surface and counting ticks before the echo returns
> Was in the eighties.
> Distance sensors are now less than 2 Euro or on ebay..
> https://www.ebay.co.uk/b/ultrasonic-distance-sensor/bn_7024750003
> done a lot of experiments with those ebay things too, for example wind speed measurements:
> http://panteltje.nl/pub/wind_speed_by_differential_2_ebay_distance_meters_IMG_4891.JPG
> http://panteltje.nl/pub/44kHz_radar_time_of_flight_test_in_wind_tunnel_IMG_4105.JPG
>
> But am from origin electronics hardware, programming came later..
> I do not always see the need for any Raspberry stuff in equipment, I use Microchip 18F14K22 chips
> that I program in asm.
> Those have ADCs, PWM generators, a simple DAC, counters, etc etc and sleep mode with only nano amps.
> For an other e dollars or so you can add an USB interface.
> For the 'network' its a bit more complicated, I need an extra chip
> As the ebay modules are so cheap who cares .
> https://www.ebay.co.uk/itm/285358235060
>
> PICs can drive a nice OLED or LCD display no problem:
> http://panteltje.nl/pub/gamma_spectrometer_plus_probe_plus_geiger_counter_2_IMG_4185.JPG
> https://panteltje.nl/panteltje/pic/scope_pic/
>
> Only external code I use is the 32 bit PIC asm math routines written by somebody else.
>
> No emulators no debuggers used ever.
> serial port and a scope is all I need.
> No million dollar scope, 10 MHz dual trace is enough.
>
> ASM is easy,
> C is OK.
> The rest I do not want to know about ;-)
> Seems these day you can ask AI to write the code...
> I wonder....
> :-)
>
>
We seem to be similar in many respects. I started out in electronics.
But as a designer, really the job died in the 1970s. After that is was
all large scale integrated chips, and there was no challenge to it. So I
taught myself software.

C to me was just a faster way to write assembler.
'if..{} else {} is quicker than MOV, CMP JNE, JMP etc etc

And the way C used the stack to allocate temporary variable space to
remove the need for complex memory management or else global memory
assignment was pure genius. I think that first appeared in ALGOL. It
allowed recursive functions to be simply coded.

--
For in reason, all government without the consent of the governed is the
very definition of slavery.

Jonathan Swift