Electrical and Computer Engineering

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Electrical and computer engineering (ECE) community, for professionals and learners. Discuss ECE related topics here, for instance digital design, signal processing, circuit analysis, electromagnetics, microelectronics, power electronics, RF electronics, etc.

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submitted 1 week ago* (last edited 1 week ago) by emotional_soup_88@programming.dev to c/ece@lemmy.world
 
 

I ordered a MiniTools test clip to start experimenting with flashing EEPROMs. There was no information on the retailer's website regarding the width of the pins. This is what I got:

I asked MiniTools if they have any solution to this. They said "no". I then realized that this clip was probably meant for soldering. Which I haven't had the energy to learn yet.

I ended up buying the expensive Pomodo one.

The flashing went well.

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cross-posted from: https://programming.dev/post/47186720

Edit: this guide doesn't seem to mention it https://pcsupport.lenovo.com/us/en/products/laptops-and-netbooks/thinkpad-t-series-laptops/thinkpad-t480-type-20l5-20l6/20l6/20l6s01q2y/document-userguide

I was flashing Libreboot on to my ThinkPad T480, when I noticed this little button. Sorry for the poor images!

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I've been researching micros for a new project. I've already got some prototype code running on an STM32F407 disco, but I thought I'd try finding a costed down option for the final design.

I was surprised to find that the STM32H725 is not only cheaper, but it can run at 550MHz, has twice the memory, and has more advanced peripherals. Even the power numbers are similar if you slow it down to 170MHz to match the STM32F4.

The only real knock I could find on the H7 is that its smallest package is 10x10 over 7x7 on the F4.

So what's the deal? Is the price based on the actual value of the chip or is there some legacy stuff priced in?

I've never worked with an M7 core. Any other caveats I should be worried about?

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submitted 2 months ago* (last edited 2 months ago) by leseci@sh.itjust.works to c/ece@lemmy.world
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Edit: this post and my questions within were poorly formulated, mostly because I made the assumption that there is a correlation between common word sizes in CPU architecture and why I couldn't find decimal to signed binary converters online that allow me to set "word size"/number of bits I want to work with.

I am a complete beginner in the field of computers.

I am reading Code - the hidden language of computer hardware and software by Charles Petzold (2009) and I just learned how we electronically express the logic of subtraction without using a minus sign or an extra bit to indicate positive/negative: we use two's complement (yes, I realize that the most significant bit incidentally acts as the sign bit, but we don't need an extra bit). Anyway, I experimented with trying to convert both decimal and binary values into their signed counterparts, just as an exercise. To be sure that I wasn't doing anything wrong, I wanted to double check my calculations with some "decimal to signed binary calculators" on the Internet.

I was trying to express -255 in signed binary using 10 bits. I wanted to use only 10 bits because I wanted to save on resources. To express the 1000 possible values between -500 and 499, I only need 10 bits, which unsigned goes between 0 and 1023. I calculated -255 to be 1100000001 in 10-bit signed binary (because 255 is 0011111111, which you invert to get to one's complement and finally you add 1).

I couldn't find any converters on the Internet that allows me to set the maximum value/length, in this case 10 bits. I found a few that are 8 bit and a few that are 16 bit, which made me think of our gaming consoles that to my knowledge evolved in increments of 8, 16, 32, 64.

I understand that we use binary to express Boolean logic and arithmetics in electronics because regulating voltage to have transistors be in one of two values is consistent with the true/false values of Boolean logic and because of the technical difficulties in maintaining stable voltages in ternary and above.

But why didn't I find any converters online that allow me to set the bit length? Why did the gaming consoles' maximum bit length evolve in those specific increments? Are there no processor architectures of other values than these?

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Hello,

I was offered a job at a casino working as a slot machine technician.

They said they do most hardware replacements and repairs, do electrical diagnostics, and even replace some capacitors or other basic electrical components; the latter maybe being mainly in the power supply area.

I worked in IT, hardware and software support, help desk and IT shop, diagnosing and replacing parts. Though, the corporate process was always buy new and swap the faulty part out with very minimal diagnosis on the electrical level.

I've left a VM with the supervisors office at the casino asking the same question. They know my limited experience in the electrical field, but also said I'll need to quickly pick up the technical aspects during the 90 day training probation on my own or I won't be brought on as permanent.

Any guidance or advice is greatly appreciated.

Thank you very much.

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Hi all,

Just got this E40HX8k FPGA. My goal is to start off small and build an 8bit adder or something and then work up to building an interface for some old Soviet core memory I have.

Does anyone have any book recommendations?

My brain vomit questions un-researched questions:

  • Is Verilog like spice but text and not analog?
  • What happens if you try to load a sketch to your board which exceeds its capabilities what happens? Can you fry it?
  • How much do you need to account for the physical layout of the board? Do you need to “move” a small sketch closer to the memory to reduce latency or does the sketch have some compilation which squishes it into the best region?
  • is there a way to visualize the final physical sketch (where it is on the board) (probably board specific.

Anyway thanks!

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Hello guys.

I'm trying to learn some more KiCAD and general electronics design from scratch by continuing my thesis project after I've submitted it and its all done, but by taking it to the next step and actually getting a PCB and soldering everything on. This is to get experience through the entire process from design to assembly.

Where I'm stuck is at creating the footprints for my components. I've watched a bunch of videos about the topic, but they all seem to be for boards with no header pins attached to them, or for pins that are vertical (perpendicular to the actual board). The two boards I have are breakout boards for a DS3231 RTC and an HM-10 BLE module, and they both have right-angle male header pins sticking out, which obviously made prototyping on a breadboard really easy, but I'm struggling with converting them to PCB.

Here are some photos to make it clearer:

HM-10:

DS3231:

I know one of my options is to desolder the right-angle header pins and add straight pins to them, but I'd like to avoid that so that I can easily use them in any future projects by simply disconnecting them from the eventual PCB and using them in a breadboard.

As such, I know that I would like there to be female headers on the final PCB, and ideally the female headers will also be at a right-angle so that the final PCB is a little more compact and there aren't just some boards sticking out from it.

So, after getting some measurements with my calipers, how can I translate them into the KiCAD footprint editor knowing the footprint should include the female right-angle header pins (which will of course extend the length of the modules beyond what I have currently measured), and also take their height into account so that they don't have any obstacles between them and the PCB as they are laying parallel to it?

I hope I made myself clear enough, but if not please feel free to ask me for any clarification.

Thanks in advance for any replies :)

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submitted 6 months ago* (last edited 6 months ago) by ruffsl@programming.dev to c/ece@lemmy.world
 
 

Relevant source code repo:

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submitted 8 months ago* (last edited 8 months ago) by ruffsl@programming.dev to c/ece@lemmy.world
 
 

An fine introduction to USB charging and Power Delivery protocols that also goes quite deep into industry approaches.

The presenter is from the automotive electronic parts market, and posted a great more recent (but more vendor specific) related video here as well:

For example, I really wish my modern Anker AC charger would at least support "Smart Power Sharing Communication" with its Dual Port configuration "via Sinc_Cap", rather than naively having total output equally for each device regardless of each device's power profile capability.

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Background:

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Hello once again everyone!

I've made considerable progress on my thesis thanks in part to you guys answering my previous post here. I'm already writing up the report, and have pretty much the entire system programmed through the Arduino.

However, I am still having difficulties figuring out how to initiate/force a disconnect of all BT devices connected to the HM-10 module (this is the one I got). You can refer to the post I made on the arduino forums (link in post) where I also searched for the solution but had no luck, but sadly its been almost 2 weeks and still no answer.

To cut a long story short, I have all the pins of the HM-10 wired except the BRK pin currently, even though I wired that up previously and tried sending LOW-HIGH-LOW and HIGH-LOW-HIGH pulses to try to disconnect. As far as I understand it, what I have is not exactly the HM-10 but an HM-10 mounted on a breakout board(?).

The data sheet on the website I got it from seems to be for the bare HM-10 so its a bit confusing for me. It talks about a specific pin (PIO0) which looks to be wired to a switch, but there is no switch or button on the actual module and that doesn't help me anyway as I want to initiate a disconnect from code.

So how can I make it disconnect from all devices when the user for example selects a certain option from the menu of my system?

As always, I will greatly appreciate any help, and of course if you need any more info let me know and I'll try to provide it.

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Hello once again everyone!

I've made considerable progress on my thesis thanks in part to you guys answering my previous post here. I'm already writing up the report, and have pretty much the entire system programmed through the Arduino.

However, I am still having difficulties figuring out how to initiate/force a disconnect of all BT devices connected to the HM-10 module (this is the one I got). You can refer to the post I made on the arduino forums (link in post) where I also searched for the solution but had no luck, but sadly its been almost 2 weeks and still no answer.

To cut a long story short, I have all the pins of the HM-10 wired except the BRK pin currently, even though I wired that up previously and tried sending LOW-HIGH-LOW and HIGH-LOW-HIGH pulses to try to disconnect. As far as I understand it, what I have is not exactly the HM-10 but an HM-10 mounted on a breakout board(?).

The data sheet on the website I got it from seems to be for the bare HM-10 so its a bit confusing for me. It talks about a specific pin (PIO0) which looks to be wired to a switch, but there is no switch or button on the actual module and that doesn't help me anyway as I want to initiate a disconnect from code.

So how can I make it disconnect from all devices when the user for example selects a certain option from the menu of my system?

As always, I will greatly appreciate any help, and of course if you need any more info let me know and I'll try to provide it.

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