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Search - "it all starts at 0"
-
Mac: Suddenly turns off
Me: Fuck my code..F***
Mac: No response at all
Me: reset SMC etc etc
Mac: I am dead (no battery detection, dies after 10 min on power adaptor)
Me: Skips a heart beat..(Git, oh yea git)
**Takes Mac to store, After diagnosis**
Apple Freaking Genius (AG): Your Mac has a mother board problem it needs to be replaced.
Me: Hmm what is the problem exactly??
AG: Issues in logic board and some other components.
Me: How much?
AG: Out of warranty so $$$ (60% of original amount)
Me: (wtf?) Really
AG: It's entire motherboard replacement .. bla bla
**Bring it home > open > everything seems ok on multimeter as per circuit diagram > finally finds a voltage drop that is not consistent > minute short circuit > remove > check further > nothing else > reassemble > hit power button > starts fine > freaking battery detected > works fine**
0 $ repair
Fixes two more devices @ 0 $ in friend circle
Builds a raspberry pi backup laptop with 3d printed body..Ubuntu.. you know can't live without a computer
#ThugLife #Engineer29 -
In a user-interface design meeting over a regulatory compliance implementation:
User: “We’ll need to input a city.”
Dev: “Should we validate that city against the state, zip code, and country?”
User: “You are going to make me enter all that data? Ugh…then make it a drop-down. I select the city and the state, zip code auto-fill. I don’t want to make a mistake typing any of that data in.”
Me: “I don’t think a drop-down of every city in the US is feasible.”
Manage: “Why? There cannot be that many. Drop-down is fine. What about the button? We have a few icons to choose from…”
Me: “Uh..yea…there are thousands of cities in the US. Way too much data to for anyone to realistically scroll through”
Dev: “They won’t have to scroll, I’ll filter the list when they start typing.”
Me: “That’s not really the issue and if they are typing the city anyway, just let them type it in.”
User: “What if I mistype Ch1cago? We could inadvertently be out of compliance. The system should never open the company up for federal lawsuits”
Me: “If we’re hiring individuals responsible for legal compliance who can’t spell Chicago, we should be sued by the federal government. We should validate the data the best we can, but it is ultimately your department’s responsibility for data accuracy.”
Manager: “Now now…it’s all our responsibility. What is wrong with a few thousand item drop-down?”
Me: “Um, memory, network bandwidth, database storage, who maintains this list of cities? A lot of time and resources could be saved by simply paying attention.”
Manager: “Memory? Well, memory is cheap. If the workstation needs more memory, we’ll add more”
Dev: “Creating a drop-down is easy and selecting thousands of rows from the database should be fast enough. If the selection is slow, I’ll put it in a thread.”
DBA: “Table won’t be that big and won’t take up much disk space. We’ll need to setup stored procedures, and data import jobs from somewhere to maintain the data. New cities, name changes, ect. ”
Manager: “And if the network starts becoming too slow, we’ll have the Networking dept. open up the valves.”
Me: “Am I the only one seeing all the moving parts we’re introducing just to keep someone from misspelling ‘Chicago’? I’ll admit I’m wrong or maybe I’m not looking at the problem correctly. The point of redesigning the compliance system is to make it simpler, not more complex.”
Manager: “I’m missing the point to why we’re still talking about this. Decision has been made. Drop-down of all cities in the US. Moving on to the button’s icon ..”
Me: “Where is the list of cities going to come from?”
<few seconds of silence>
Dev: “Post office I guess.”
Me: “You guess?…OK…Who is going to manage this list of cities? The manager responsible for regulations?”
User: “Thousands of cities? Oh no …no one is our area has time for that. The system should do it”
Me: “OK, the system. That falls on the DBA. Are you going to be responsible for keeping the data accurate? What is going to audit the cities to make sure the names are properly named and associated with the correct state?”
DBA: “Uh..I don’t know…um…I can set up a job to run every night”
Me: “A job to do what? Validate the data against what?”
Manager: “Do you have a point? No one said it would be easy and all of those details can be answered later.”
Me: “Almost done, and this should be easy. How many cities do we currently have to maintain compliance?”
User: “Maybe 4 or 5. Not many. Regulations are mostly on a state level.”
Me: “When was the last time we created a new city compliance?”
User: “Maybe, 8 years ago. It was before I started.”
Me: “So we’re creating all this complexity for data that, realistically, probably won’t ever change?”
User: “Oh crap, you’re right. What the hell was I thinking…Scratch the drop-down idea. I doubt we’re have a new city regulation anytime soon and how hard is it to type in a city?”
Manager: “OK, are we done wasting everyone’s time on this? No drop-down of cities...next …Let’s get back to the button’s icon …”
Simplicity 1, complexity 0.16 -
Friend of mine killed his MacBook with some Softdrink.
Just poured it all over his poor a1502.
He let it dry for a few days, it starts to work again.
Except the battery.
Goes on Amazon and buys a new battery.
New battery doesn't work either and so he tells me about it and I as stupid as I am couldn't resist the temptation to finally work on a MacBook like my "hero" Lois Rossmann does.
So turns out the board is good.
Cleaned it up and basically nothing happened to it.
So what's the deal with "los batlerias"?
The first got hit by liquid, the second had a broken connection to a cell.
That could have happened through my friend, installing it without testing it first, or at the seller, so it being a DOA battery.
Now away from the stupidity of my friend and the situation to the actual source for this rant.
Once something happens to a modern Managed battery, the Battery Management System (BMS) disconnects the voltage from the system and goes into an error state, staying there and not powering anything ever again.
For noobs, it's dead. Buy a new one.
But It can be reset, depending you know how to, and which passwords were set at the factory.
Yes, the common Texas instruments BQ20Zxx chips have default passwords, and apple seems to leav them at default.
The Usb to SMBus adaptors arrived a few days ago and I went to prod the BMS.
There is a very nice available for Windows called BE2works, that I used the demo of to go in and figure out stuff. The full version supports password cracking, the demo not.
After some time figuring out how Smart Battery Systems (SBS) "API" works, I got to actually enter the passwords into the battery to try get into manufacturer and full access mode.
Just to realise, they don't unlock the BMS.
So, to conclude, my friend bought a "new" battery that was most likely cut out of a used / dead macbook, which reports 3000mah as fully charged instead of the 6xxx mah that it should have, with 0 cycles and 0hours used.
And non default access.
This screams after those motherfuckers scaming the shit out of people on Amazon, with refurb, reset, and locked fucken batteries.
I could kill those people right now.
Last but not least,
My friend theoretically can't send it back because I opened the battery to fix the broken connection.
Though maybe, it'll get send back anyway, with some suprise in the package.9 -
I had to open the desktop app to write this because I could never write a rant this long on the app.
This will be a well-informed rebuttal to the "arrays start at 1 in Lua" complaint. If you have ever said or thought that, I guarantee you will learn a lot from this rant and probably enjoy it quite a bit as well.
Just a tiny bit of background information on me: I have a very intimate understanding of Lua and its c API. I have used this language for years and love it dearly.
[START RANT]
"arrays start at 1 in Lua" is factually incorrect because Lua does not have arrays. From their documentation, section 11.1 ("Arrays"), "We implement arrays in Lua simply by indexing tables with integers."
From chapter 2 of the Lua docs, we know there are only 8 types of data in Lua: nil, boolean, number, string, userdata, function, thread, and table
The only unfamiliar thing here might be userdata. "A userdatum offers a raw memory area with no predefined operations in Lua" (section 26.1). Essentially, it's for the API to interact with Lua scripts. The point is, this isn't a fancy term for array.
The misinformation comes from the table type. Let's first explore, at a low level, what an array is. An array, in programming, is a collection of data items all in a line in memory (The OS may not actually put them in a line, but they act as if they are). In most syntaxes, you access an array element similar to:
array[index]
Let's look at c, so we have some solid reference. "array" would be the name of the array, but what it really does is keep track of the starting location in memory of the array. Memory in computers acts like a number. In a very basic sense, the first sector of your RAM is memory location (referred to as an address) 0. "array" would be, for example, address 543745. This is where your data starts. Arrays can only be made up of one type, this is so that each element in that array is EXACTLY the same size. So, this is how indexing an array works. If you know where your array starts, and you know how large each element is, you can find the 6th element by starting at the start of they array and adding 6 times the size of the data in that array.
Tables are incredibly different. The elements of a table are NOT in a line in memory; they're all over the place depending on when you created them (and a lot of other things). Therefore, an array-style index is useless, because you cannot apply the above formula. In the case of a table, you need to perform a lookup: search through all of the elements in the table to find the right one. In Lua, you can do:
a = {1, 5, 9};
a["hello_world"] = "whatever";
a is a table with the length of 4 (the 4th element is "hello_world" with value "whatever"), but a[4] is nil because even though there are 4 items in the table, it looks for something "named" 4, not the 4th element of the table.
This is the difference between indexing and lookups. But you may say,
"Algo! If I do this:
a = {"first", "second", "third"};
print(a[1]);
...then "first" appears in my console!"
Yes, that's correct, in terms of computer science. Lua, because it is a nice language, makes keys in tables optional by automatically giving them an integer value key. This starts at 1. Why? Lets look at that formula for arrays again:
Given array "arr", size of data type "sz", and index "i", find the desired element ("el"):
el = arr + (sz * i)
This NEEDS to start at 0 and not 1 because otherwise, "sz" would always be added to the start address of the array and the first element would ALWAYS be skipped. But in tables, this is not the case, because tables do not have a defined data type size, and this formula is never used. This is why actual arrays are incredibly performant no matter the size, and the larger a table gets, the slower it is.
That felt good to get off my chest. Yes, Lua could start the auto-key at 0, but that might confuse people into thinking tables are arrays... well, I guess there's no avoiding that either way.13 -
Most satisfying bug I've fixed?
Fixed a n+1 issue with a web service retrieving price information. I initially wrote the service, but it was taken over by a couple of 'world class' monday-morning-quarterbacks.
The "Worst code I've ever seen" ... "I can't believe this crap compiles" types that never met anyone else's code that was any good.
After a few months (yes months) and heavy refactoring, the service still returned price information for a product. Pass the service a list of product numbers, service returns the price, availability, etc, that was it.
After a very proud and boisterous deployment, over the next couple of days the service seemed to get slower and slower. DBAs started to complain that the service was causing unusually high wait times, locks, and CPU spikes causing problems for other applications. The usual finger pointing began which ended up with "If PaperTrail had written the service 'correctly' the first time, we wouldn't be in this mess."
Only mattered that I initially wrote the service and no one seemed to care about the two geniuses that took months changing the code.
The dev manager was able to justify a complete re-write of the service using 'proper development methodologies' including budgeting devs, DBAs, server resources, etc..etc. with a projected year+ completion date.
My 'BS Meter' goes off, so I open up the code, maybe 5 minutes...tada...found it. The corresponding stored procedure accepts a list of product numbers and a price type (1=Retail, 2=Dealer, and so on). If you pass 0, the stored procedure returns all the prices.
Code basically looked like this..
public List<Prices> GetPrices(List<Product> products, int priceTypeId)
{
foreach (var item in products)
{
List<int> productIdsParameter = new List<int>();
productIdsParameter.Add(item.ProductID);
List<Price> prices = dataProvider.GetPrices(productIdsParameter, 0);
foreach (var price in prices)
{
if (price.PriceTypeID == priceTypeId)
{
prices = dataProvider.GetPrices(productIdsParameter, price.PriceTypeID);
return prices;
}
* Omitting the other 'WTF?' code to handle the zero price type
}
}
}
I removed the double stored procedure call, updated the method signature to only accept the list of product numbers (which it was before the 'major refactor'), deployed the service to dev (the issue was reproducible in our dev environment) and had the DBA monitor.
The two devs and the manager are grumbling and mocking the changes (they never looked, they assumed I wrote some threading monstrosity) then the DBA walks up..
DBA: "We're good. You hit the database pretty hard and the CPU never moved. Execution plans, locks, all good to go."
<dba starts to walk away>
DevMgr: "No fucking way! Putting that code in a thread wouldn't have fix it"
Me: "Um, I didn't use threads"
Dev1: "You had to. There was no way you made that code run faster without threads"
Dev2: "It runs fine in dev, but there is no way that level of threading will work in production with thousands of requests. I've got unit tests that prove our design is perfect."
Me: "I looked at what the code was doing and removed what it shouldn't be doing. That's it."
DBA: "If the database is happy with the changes, I'm happy. Good job. Get that service deployed tomorrow and lets move on"
Me: "You'll remove the recommendation for a complete re-write of the service?"
DevMgr: "Hell no! The re-write moves forward. This, whatever you did, changes nothing."
DBA: "Hell yes it does!! I've got too much on my plate already to play babysitter with you assholes. I'm done and no one on my team will waste any more time on this. Am I clear?"
Seeing the dev manager face turn red and the other two devs look completely dumbfounded was the most satisfying bug I've fixed.5 -
So recently I did a lot of research into the internals of Computers and CPUs.
And i'd like to share a result of mine.
First of all, take some time to look at the code down below. You see two assembler codes and two command lines.
The Assembler code is designed to test how the instructions "enter" and "leave" compare to manually doing what they are shortened to.
Enter and leave create a new Stackframe: this means, that they create a new temporary stack. The stack is where local variables are put to by the compiler. On the right side, you can see how I create my own stack by using
push rbp
mov rbp, rsp
sub rsp, 0
(I won't get into details behind why that works).
Okay. Why is this even relevant?
Well: there is the assumption that enter and leave are very slow. This is due to raw numbers:
In some paper I saw ( I couldn't find the link, i'm sorry), enter was said to use up 12 CPU cycles, while the manual stacking would require 3 (push + mov + sub => 1 + 1 + 1).
When I compile an empty function, I get pretty much what you'd expect just from the raw numbers of CPU cycles.
HOWEVER, then I add the dummy code in the middle:
mov eax, 123
add eax, 123543
mov ebx, 234
div ebx
and magically - both sides have the same result.
Why????
For one thing, there is CPU prefetching. This is the CPU loading in ram before its done executing the current instruction (this is how anti-debugger code works, btw. Might make another rant on that). Then there is the fact that the CPU usually starts work on the next instruction while the current instruction is processing IFF the register currently involved isnt involved in the next instruction (that would cause a lot of synchronisation problems). Now notice, that the CPU can't do any of that when manually entering and leaving. It can only start doing the mov eax, 1234 while performing the sub rsp, 0.
----------------
NOW: notice that the code on the right didn't take any precautions like making sure that the stack is big enough. If you sub too much stack at once, the stack will be exhausted, thats what we call a stack overflow. enter implements checks for that, and emits an interrupt if there is a SO (take this with a grain of salt, I couldn't find a resource backing this up). There are another type of checks I don't fully get (stack level checks) so I'd rather not make a fool of myself by writing about them.
Because of all those reasons I think that compilers should start using enter and leave again.
========
This post showed very well that bare numbers can often mislead.21 -
Got demoted, got a pay raise and don't know how to feel about it. A story of how not to drink with your coworkers?
The story begins roughly 8-9 months ago. Me and this coworker (let's name him Tim) go out drinking after a Friday party at the office. We do some rounds and we're both smashed. Tim starts telling me how he's happy with life and that he's earning a nice salary right now. He told me his salary. It was the same as mine. Which was weird - He codes in a more hardcore languages than me and has almost double the time in the company as me. I think after some more drinking I've confessed that I make the same as him. This part is sort of a blur (drinking). I've gotten a pay raise(+30-40%) roughly a few months ago from that point backwards because another company gave be a much higher offer. The company I work for matched to keep me. Anyway, 3 months or so after the drinking,Tim is promoted to team lead, and me and a few other people are added to his team. Conversation slips and he told me his new salary - quite a bit more than me.I think it's safe to assume what happened.
The problem with that is that I was a team lead of 1 person (me) at that time, and I was managing my own time and my own tasks, was working with people individually. I was part of the weekly meetings with the CEO and other team leads. Being stripped of this title wasn't a problem at the beginning, as people still contacted me because of their problems, suggestions, whatever. A few more months pass (to now) and less and less people are contacting me - instead they are talking with Tim, and are asking of his opinion on tasks I should do, where he has no experience and roughly 0 lines in the programming language I code in. This is starting to piss me off.
There are a couple other things to take into consideration as well - The company is hiring a lot of people right now. The whole structure for team leads changed a bit, more team leads then ever right now and new roles added pretty fast.
I've gotten a pay raise a few weeks ago though(10%~).
I'm not sure on how to react to this. Should I comply and just keep on working on these tasks? Or should I still keep contacting people directly on their requests and talk to them directly, take credit for the projects I complete publicly and the stuff I do as I was previously doing? Part of me wants to reroute all of the stupids questions people have to Tim, as he is now responsible for these tasks and get this weight off my shoulders.
I'm starting to shift to learning a new programming language and thinking of jumping ship. Thoughts?6 -
Fuck everything about Microsoft Dynamics. I'm supposed to use the REST API to make a web front-end. I notice all of the data comes back codified.
null == 0.
boolean true == 100000000
boolean false == 100000001
except sometimes when
boolean false == 100000000
boolean true == 100000001
or other times
string "Yes" == 100000000
string "No" == 100000001
string "Maybe" == 100000003
Hang on. Is the system representing a 1 bit value with base 10 numbers? Did the client set this up like this? Holy crap every number corresponds to a unique record in a table somewhere. That means it only returns numeric values instead of strings and I have to figure out what the number means in the context of the table.
A "key" is user typed? So every time someone starts to make a new record it saves a new "key" without a record? So I can pull a bunch of "0" records if I pull sequentially? So basically I need to see all of the data in Dynamics to have any context at all for what is returned from the Dynamics API? Fuuuuuuuuuu10 -
Still looking for my first full-time dev role. After being endlessly rejected from every dev job I've applied for, it starts to eat away at your confidence. Makes me wonder if I'm not as competent as I believe I am. :/
Fortunately, I landed a coding interview with Google! It is my dream job to work at Google, so the fact that they even acknowledged me & my skillset makes me so happy and reaffirms my belief in my capabilities. :D
It's pretty odd, that after applying to 20+ open Google positions relevant to my skill level & location and often with references included, then having been rejected from all of them, that I finally got a chance with them when one of their recruiters found me on LinkedIn and liked what she saw. I cleared the screening call, and made it to the first coding interview.
Of course, even with all the interview prep I've done, it was all practically for naught since they caught me off guard with a crazy conceptual problem anyway. (Well, actually, was I 'caught off guard' if I was already expecting to be caught off guard? o.0) I struggled heavily in the first half of the interview, but found my footing towards the end. So I knew I screwed up and that it was highly unlikely for me to get the job.
Nonetheless, Google had the decency to reject me not via an automated email, but through an actual direct phone call with my recruiter. (The cruelty of the automated application rejection system in our society is a whole rant of its own, for another time.) My recruiter told me that they felt I wasn't ready but they liked what they saw, so they will be revisiting me in exactly a year to reconsider me.
To know that I wasn't fully rejected, and that my dream company Google sees real potential in me, is highly reassuring. It means I'm not a lost cause; I simply need to keep looking. Google will want me more strongly once I have the experience that comes from a fresh grad's first full-time job.8 -
After learning a bit about alife I was able to write
another one. It took some false starts
to understand the problem, but afterward I was able to refactor the problem into a sort of alife that measured and carefully tweaked various variables in the simulator, as the algorithm
explored the paramater space. After a few hours of letting the thing run, it successfully returned a remainder of zero on 41.4% of semiprimes tested.
This is the bad boy right here:
tracks[14]
[15, 2731, 52, 144, 41.4]
As they say, "he ain't there yet, but he got the spirit."
A 'track' here is just a collection of critical values and a fitness score that was found given a few million runs. These variables are used as input to a factoring algorithm, attempting to factor
any number you give it. These parameters tune or configure the algorithm to try slightly different things. After some trial runs, the results are stored in the last entry in the list, and the whole process is repeated with slightly different numbers, ones that have been modified
and mutated so we can explore the space of possible parameters.
Naturally this is a bit of a hodgepodge, but the critical thing is that for each configuration of numbers representing a track (and its results), I chose the lowest fitness of three runs.
Meaning hypothetically theres room for improvement with a tweak of the core algorithm, or even modifications or mutations to the
track variables. I have no clue if this scales up to very large semiprime products, so that would be one of the next steps to test.
Fitness also doesn't account for return speed. Some of these may have a lower overall fitness, but might in fact have a lower basis
(the value of 'i' that needs to be found in order for the algorithm to return rem%a == 0) for correctly factoring a semiprime.
The key thing here is that because all the entries generated here are dependent on in an outer loop that specifies [i] must never be greater than a/4 (for whatever the lowest factor generated in this run is), we can potentially push down the value of i further with some modification.
The entire exercise took 2.1735 billion iterations (3-4 hours, wasn't paying attention) to find this particular configuration of variables for the current algorithm, but as before, I suspect I can probably push the fitness value (percentage of semiprimes covered) higher, either with a few
additional parameters, or a modification of the algorithm itself (with a necessary rerun to find another track of equivalent or greater fitness).
I'm starting to bump up to the limit of my resources, I keep hitting the ceiling in my RAD-style write->test->repeat development loop.
I'm primarily using the limited number of identities I know, my gut intuition, combine with looking at the numbers themselves, to deduce relationships as I improve these and other algorithms, instead of relying strictly on memorizing identities like most mathematicians do.
I'm thinking if I want to keep that rapid write->eval loop I'm gonna have to upgrade, or go to a server environment to keep things snappy.
I did find that "jiggling" the parameters after each trial helped to explore the parameter
space better, so I wrote some methods to do just that. But what I wouldn't mind doing
is taking this a bit of a step further, and writing some code to optimize the variables
of the jiggle method itself, by automating the observation of real-time track fitness,
and discarding those changes that lead to the system tending to find tracks with lower fitness.
I'd also like to break up the entire regime into a training vs test set, but for now
the results are pretty promising.
I knew if I kept researching I'd likely find extensions like this. Of course tested on
billions of semiprimes, instead of simply millions, or tested on very large semiprimes, the
effect might disappear, though the more i've tested, and the larger the numbers I've given it,
the more the effect has become prevalent.
Hitko suggested in the earlier thread, based on a simplification, that the original algorithm
was a tautology, but something told me for a change that I got one correct. Without that initial challenge I might have chalked this up to another false start instead of pushing through and making further breakthroughs.
I'd also like to thank all those who followed along, helped, or cheered on the madness:
In no particular order ,demolishun, scor, root, iiii, karlisk, netikras, fast-nop, hazarth, chonky-quiche, Midnight-shcode, nanobot, c0d4, jilano, kescherrant, electrineer, nomad,
vintprox, sariel, lensflare, jeeper.
The original write up for the ideas behind the concept can be found at:
https://devrant.com/rants/7650612/...
If I left your name out, you better speak up, theres only so many invitations to the orgy.
Firecode already says we're past max capacity!5 -
So I wrote these E2E tests to test my credit card expiration notification emails. So I wrote my code, and tested it. Tests failed. I spent the next 6 hours (spanning 2 days) debugging my tests. Come to find out that the tests were fine all along. The issue was my code.
Apparently everything has dates starting at 1 (day starts at 1, year starts at 1). But MONTHS. Months start at 0 -
Can anyone help me with this theory about microprocessor, cpu and computers in general?
( I used to love programming when during school days when it was just basic searching/sorting and oop. Even in college , when it advanced to language details , compilers and data structures, i was fine. But subjects like coa and microprocessors, which kind of explains the working of hardware behind the brain that is a computer is so difficult to understand for me 😭😭😭)
How a computer works? All i knew was that when a bulb gets connected to a battery via wires, some metal inside it starts glowing and we see light. No magics involved till now.
Then came the von Neumann architecture which says a computer consists of 4 things : i/o devices, system bus ,memory and cpu. I/0 and memory interact with system bus, which is controlled by cpu . Thus cpu controls everything and that's how computer works.
Wait, what?
Let's take an easy example of calc. i pressed 1+2= on keyboard, it showed me '1+2=' and then '3'. How the hell that hapenned ?
Then some video told me this : every key in your keyboard is connected to a multiplexer which gives a special "code" to the processer regarding the key press.
The "control unit" of cpu commands the ram to store every character until '=' is pressed (which is a kind of interrupt telling the cpu to start processing) . RAM is simply a bunch of storage circuits (which can store some 1s) along with another bunch of circuits which can retrieve these data.
Up till now, the control unit knows that memory has (for eg):
Value 1 stored as 0001 at some address 34A
Value + stored as 11001101 at some address 34B
Value 2 stored as 0010 at some Address 23B
On recieving code for '=' press, the "control unit" commands the "alu" unit of cpu to fectch data from memory , understand it and calculate the result(i e the "fetch, decode and execute" cycle)
Alu fetches the "codes" from the memory, which translates to ADD 34A,23B i.e add the data stored at addresses 34a , 23b. The alu retrieves values present at given addresses, passes them through its adder circuit and puts the result at some new address 21H.
The control unit then fetches this result from new address and via, system busses, sends this new value to display's memory loaded at some memory port 4044.
The display picks it up and instantly shows it.
My problems:
1. Is this all correct? Does this only happens?
2. Please expand this more.
How is this system bus, alu, cpu , working?
What are the registers, accumulators , flip flops in the memory?
What are the machine cycles?
What are instructions cycles , opcodes, instruction codes ?
Where does assembly language comes in?
How does cpu manipulates memory?
This data bus , control bus, what are they?
I have come across so many weird words i dont understand dma, interrupts , memory mapped i/o devices, etc. Somebody please explain.
Ps : am learning about the fucking 8085 microprocessor in class and i can't even relate to basic computer architecture. I had flunked the coa paper which i now realise why, coz its so confusing. :'''(14