Welcome to the Lounge

14-Jul-21 11:42

I'm rolling my own everything, as is often the case when targeting a new platform with new things. It's fun. There's a whole lot of challenge. First was a graphics engine and several drivers, then a true type engine for constrained memory environments, now an unzipping engine for constrained environments.

If you code in C or C++, take a look at this cool stuff:
GitHub - nothings/stb: stb single-file public domain libraries for C/C++[^]

There are gobs of useful public domain code that can teach you how to do all manner of things. They are dependency free single header file implementations to do various very cool things. I'm using the modified guts of one of them in my truetype engine, and the guts of another for my unzipping engine, and probably more of that (stb_image) to revamp my image loading to support more formats.

They're a bit messy, but still cool and the (lack of) license is awesome.

Anyway, I've had to modify all of the code that I've found here because it's geared for desktops and so it happily allocates RAM like you have infinite of it, but that's part of the fun.

I strongly encourage folks to code IoT stuff. It forces you to understand the inner workings of all the nonsense you take for granted with coding today.

Cheers. Smile | :)

Real programmers use butterflies

lmoelleb14-Jul-21 21:24

lmoelleb

14-Jul-21 21:24

Luckily (unfortunately) I am old enough that I already know most of this stuff, but I still enjoy IoT programming in the very limited time I have for it. It takes me back to the time where we wrote code, unlike now where 90% of the time is spend fighting 3rd party libraries and trying to get our code deployed somewhere it will run.

honey the codewitch14-Jul-21 22:22

14-Jul-21 22:22

Coding IoT reminds me of when I began coding on little 8 bit and 16 bit monsters back in the mid 1980s.

I know, an Apple ][e is not a PDP-11 and I am a whippersnapper. I'll get off your lawn. Poke tongue | ;-P

Real programmers use butterflies

User 991608015-Jul-21 4:13

User 9916080

15-Jul-21 4:13

Awesome! I started programming on a Radio Shack Micro computer 10 with the 16k expansion model back in 83. My first program was slots (slot machine). I then started my big program, a text based Star Trek game. Later, I added graphics, all done in BasicA.

[Edit] Sorry about that. My original response came across as a little rude. [/Edit]

"When you are dead, you won't even know that you are dead. It's a pain only felt by others; same thing when you are stupid."

Ignorant - An individual without knowledge, but is willing to learn.
Stupid - An individual without knowledge and is incapable of learning.
Idiot - An individual without knowledge and allows social media to do the thinking for them.

modified 19-Nov-21 21:01pm.

honey the codewitch15-Jul-21 4:56

15-Jul-21 4:56

I didn't think you were being rude. I was just being silly. I learned to code in 1986 on the hateful/ill fated Apple ][gs.

John Scully will forever have my ire.

I started in Applesoft, then learned 6502 bytecode (call -151) before realizing there was a built in mini assembler (!), so I learned that

I learned the 65c816 specific stuff far later, so I was basically coding 8 bit on a 16 bit machine.

Real programmers use butterflies

CodeWraith14-Jul-21 22:53

CodeWraith

14-Jul-21 22:53

Nah. Take a good old 8 bit processor and build your own little computer. And then you fire up the assembler and start at memory address 0000 with something like this:

        LDI  HI(StackTop)
        PHI  R2
        LDI  LO(StackTop)
        PLO  R2
        LDI  HI(Main)
        PHI  R3
        LDI  LO(Main)
        PLO  R3
        LDI  HI(StdCallProcedure)
        PHI  R4
        LDI  LO(StdCallProcedure)
        PLO  R4
        LDI  HI(StdReturnProcedure)
        PHI  R5
        LDI  LO(StdReturnProcedure)
        PLO  R5
        SEX  R2
        SEP  R3

Main:   ...

And it must be a good old 8 bit or early 16 bit processor because you don't want to buy equipment at the price of real estate or study quantum mechanics to explain why your design does not work.

I have lived with several Zen masters - all of them were cats.

His last invention was an evil Lasagna. It didn't kill anyone, and it actually tasted pretty good.

honey the codewitch15-Jul-21 0:28

15-Jul-21 0:28

I used to do that kind of thing back in the 80s on 6502s. Now I prefer the challenge of crafting C++ code that generates the precise assembly code I want (or better than what I would have written)

Real programmers use butterflies

Another: Rolling rolling rolling

Forogar 15-Jul-21 2:47

Forogar

15-Jul-21 2:47

I remember doing stuff in 6502 assembler on my Commodore PET and BBC computers - yay, nostalgia!

- I would love to change the world, but they won’t give me the source code.

Nelek15-Jul-21 0:39

Nelek

15-Jul-21 0:39

Rollin' rollin' rollin'[^]
Roll eyes | :rolleyes:

M.D.V.

If something has a solution... Why do we have to worry about?. If it has no solution... For what reason do we have to worry about?
Help me to understand what I'm saying, and I'll explain it better to you
Rating helpful answers is nice, but saying thanks can be even nicer.

User 991608015-Jul-21 4:09

User 9916080

15-Jul-21 4:09

Awesome! Thanks for the link and congrats on your progress. Sounds amazing.

I'm currently working on a tracker system that uses a custom PCB with the latest chipsets, so everything has to be written from scratch. Me and two friends have two patents on the system and hopefully, we will be going to manufacturing early next year.

modified 19-Nov-21 21:01pm.

honey the codewitch15-Jul-21 4:59

15-Jul-21 4:59

Cool. I've got a custom hardware project that is currently being prototyped right now. It's a smart version of an earlier device and I have to develop everything from scratch but also to an existing specification, which is both great that they have one, and challenging that I can't dictate my own requirements (you know how it is I'm sure)

Even then, I do have a lot of creative freedom on the project, and I've de facto taken over the hardware development of it too, even though my direct contact for the project is the electrical engineer. Laugh | :laugh:

Real programmers use butterflies

Nelek15-Jul-21 4:21

Nelek

15-Jul-21 4:21

honey the codewitch wrote:
I strongly encourage folks to code IoT stuff. It forces you to understand the inner workings of all the nonsense you take for granted with coding today.

That's why I did recommend (time ago) to start with automation in PLC or robotics, back then they had way smaller resources and you had to think a bit sometimes to make it faster or even possible.

Current PLCs are not comparable anymore. They can handle very big things and you really have to do things really bad to reach the limits.

M.D.V.

modified 15-Jul-21 10:34am.

honey the codewitch15-Jul-21 4:53

15-Jul-21 4:53

So you just do *more* with it. Push the envelope again. I've got TrueType running on 512kB systems with 300kB available, and it's not uncommon for TTF streams to be north of 200kB

I did it by streaming the data for rendering the font straight from the stream. Then I only malloc temporarily while rendering on a character by character basis. It can probably target machines with far less RAM than 300kB but I haven't tested it on say, an ARM yet.

I also am making an EPUB reader, which ties in Zip file technology, epaper display driver tech, HTML/CSS, XML and JPG+PNG

The zip file portion I'm working on right now. In order to make it work with big books, like decompressed EPUBs with pictures that end up uncompressed to larger than 4MB, I am making the zip engine stream on demand directly from the file so it never has to decompress the zip entirely.

Even then, I need every byte of my 4MB of NVS flash to hold my program code and any scratch data I need to make the epub thing work.

It's serious business, cramming big things into little packages. As the packages get bigger, just get more ambitious with what you cram into it.

Real programmers use butterflies

Nelek15-Jul-21 6:27

Nelek

15-Jul-21 6:27

honey the codewitch wrote:
So you just do *more* with it.

Once thing is willing to try it, another thing is actually doing it.

You might be a bit crazy (your own words), but I just think you are as crazy as a genious need to be, to remain so damned creative and out of the box.

I try to follow many things of what you do, but I actually can't. You are just way ahead of me.

M.D.V.

honey the codewitch15-Jul-21 7:21

I bought a multimeter long time ago

15-Jul-21 7:21

I appreciate the sentiment, but I'm more tenacious than anything. That and curiosity keeps me going.

I think you can keep up. A lot of the problems I solve are problems that you'd have solved too had you run into them, I swear. You work more than I do though, I bet. I have a lot of disposable time. Smile | :)

Real programmers use butterflies

Southmountain14-Jul-21 8:12

Southmountain

14-Jul-21 8:12

I plan to test some computer parts, but I did not get time to do it.
now my refrigerator did not freeze, so I used it to test defrost heater.

diligent hands rule....

Slacker00714-Jul-21 8:17

Slacker007

14-Jul-21 8:17

excellent.

I have used my multimeter on many troubleshooting projects around the house over the years.

OriginalGriff14-Jul-21 8:34

OriginalGriff

14-Jul-21 8:34

Oh yes.
Checking fuses, batteries, temperature, ... the list goes on.
I have several: two digital (so I can check the batteries in the other - and one has a current clamp the other doesn't) and a pair of Avo 8 analogue meters.

"I have no idea what I did, but I'm taking full credit for it." - ThisOldTony
"Common sense is so rare these days, it should be classified as a super power" - Random T-shirt
AntiTwitter: @DalekDave is now a follower!

Southmountain14-Jul-21 9:19

Southmountain

14-Jul-21 9:19

but my problem is : I forgot my initial goals: what kinds of computer parts I can check? I liked Dell laptops and desktops.
so I bought lot of stuff from eBay...

diligent hands rule....

Message Closed

14-Jul-21 17:15

Member 14968771

14-Jul-21 17:15

Message Closed

modified 15-May-23 19:07pm.

OriginalGriff14-Jul-21 18:33

OriginalGriff

14-Jul-21 18:33

Member 14968771 wrote:
unplug the faulty module and replace it , throw the bad one away

Cut it in half and throw it away - I learned that with cables decades ago. It you don't, some bugger will fish it out of he bin and it'll come back to haunt you ... Unsure | :~

dshillito14-Jul-21 23:29

dshillito

14-Jul-21 23:29

Member 14968771 wrote:
The problem with "cheap" multimeters - the test probes do not last....

Ain't that the truth.
I had a multimeter that I bought in the early 1970s. Of course, from that era, it was still an analog meter with a needle. This is it (at the Radio Museum): Multimeter 200H Equipment Central; where?, build 1973 ??, 3[^]

It lasted me over 40 years but it was the probes that wore out and I found I could buy a cheap new digital multimeter for less than the cost of a new set of probes. That digital meter lasted me 5 or 6 years and then those probes wore out and again it was cheaper to buy a new meter than to get a replacement set of probes.

jkirkerx15-Jul-21 8:15

jkirkerx

15-Jul-21 8:15

Buy a Fluke, they last forever and the leads never break, plus auto shutoff to save the battery. I have 3 different flukes from when I was a data communications contractor, even one to read amperage drawn on power cables because I had an electrical contractors license as well.

I haven't tested a transistor since my Xerox days in the 80's, or Mosfets for car audio amplifiers. Never tested diodes, because most AC to DC converter chip have them built in.

If it ain't broke don't fix it
Discover my world at jkirkerx.com

sasadler15-Jul-21 6:42

sasadler

15-Jul-21 6:42

One of the more likely failures, in devices that have power supplies, are the electrolytic capacitors in the supply. My ex-boss (I'm retired now) had 2 TVs fail on him and both failures were from the electrolytic capacitors in the supply. He was able to fix both TVs by replacing the capacitors. Normally, the bad capacitors are bulging.