I was gifted this ~2010 Toshiba Portégé. Surprisingly small and thin for its age. I was hoping to revive it, but it has only 1GB of memory ootb.

Apparently it can be upgraded up to 5GB with one spare slot that currently sits empty.

I found 2 physically compatible identical 2GB modules but no matter which one I plug in, when I start the computer it just starts the fan on highest setting and nothing else happens.

Before I go into any more detail, I found this info online:

The Toshiba Portege R600 Laptop takes the PC2-6400 DDR2-800 200pin SDRAM SODIMM memory type

My sticks look like this:

Are they compatible to PC2-6400 DDR2-800 200pin SDRAM SODIMM? I honestly can't tell.

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I read the manual which says the modules need to be "Toshiba approved" but it does not say which/what Toshiba approves.

Plus this, which I did follow (note the negative):

Do not try to install or remove a memory module under the following conditions.

a. The computer is turned on.
b. The computer was shut down in either Sleep or Hibernation Mode.
c. Wake-up on LAN is enabled.
d. Wake-up on Wireless LAN is enabled.
e. The wireless communication switch is turned on.

And this does not happen:

If you install a memory module that is not compatible with the computer, the Power indicator will flash (on for 0.5 seconds, off for 0.5 seconds) in the following way;
■ If there is an error: repeatedly flashes orange twice, then white or green once

The power indicator ⏻ stays white all the time and does not blink.

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TIA

So i have these Rode Wireless Microphones at Work that you connect to your phone with a USB-C cable. Thing is the cable they ship with is absolute trash and breaks after about 3 uses. So i got the idea to try and build a 3d printed thingie with a protruding usb-c port that you could slide onto your phone sort of like the old iphone music docks. Then on the back you could slide in the rode receiver, thus eliminating any cable twisting. I thought this would be easiest if i had the pictured usb-c breakouts, because they have mounting holes that i could fix firmly into the 3d printed part. I picked a 24 pin version thinking this would cover all the necessary usb-c specs to get at least something like a usb 3.0 connection as I don't think the rode mics need super high data transfer or power delivery above 5v. Alas the pictured "cable" didn't do the trick and the mic wasn't recognized by the phone. So I'm wondering would it even be possible to build something like this with breakouts or am I missing things. Do usb-c cables usually have chips that negotiate voltage and transfer specs between devices? Am i missing shielding, or is my wire gauge totally off?

I can probably still build a mic holder thingy using a short premade silicone cable, but I'm still curious if this setup could work in theory or if there are other breakouts that could make this work.

Thanks for your help!

AVR is one of my favorite chips as a hobbyist. 8-bits, manuals in the less than 500 pages region (very small compared to Cortex-M0+ which are closer to the 1000 or 2000 page long regions if we include instruction sets and other details), etc. etc. So I'm happy to see Microchip continue to support simpler 8-bit chips for those who need them.

For those looking to use this chip exactly: it seems like AVR LA specializes in low-cost, low-power, and capacitive touch. Most components have been stripped out, the ADC is only 10-bits, there's no more dual power supply (like AVR DD, DB, or DA), there's no special features like op-amps (AVR DB), or programmable gain differential ADCs (like AVR EA or EB).

You do get event system, CCLs (AVR's feature of LUTs, functioning as useful "glue logic" that can implement a few simple XOR, AND, OR, NOT gates for those who need simple glue), RTC, and PTC (aka: Peripheral Touch Controller, Microchip's system of building capacitive touch).

At 1.62V minimum (and up to 5.5V maximum), this is seemingly the lowest voltage I've seen from AVR lines. For anyone with a buck or boost converter in their designs, this should lower power usage a fair bit over the 1.8V previous minimums.

Finally, the 5k unit pricing is around 50-cents or so. This is the cheapest AVR 8-bit you can buy, if anyone were doing a large scale mass manufacturing line. But for most hobbyistss, I don't believe we can sufficiently tell the difference between 50c chips and $2.00 chips.

So its very barebones outside of capacitive touch. Still, this shows a commitment from Microchip to continue to support AVR chips and their ecosystem. I would recommend beginners use the AVR DB instead (which come with 3x OpAmps and far more features), unless you really want a barebones capacitive touch controller.

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.

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!

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?

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?