quiescentcurrent

joined 1 year ago
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safe? in c/[email protected]
[–] [email protected] 15 points 1 week ago (1 children)

Then this is not safe.

The maximum charge voltage for a lithium cell is 4.2V while USB will provide 5V. It may work for a while, it may fail in a safe state or something gets hot and burns.

I never knew that USB-C extensions are not allowed for a reason in c/[email protected]
[–] [email protected] 13 points 1 month ago

Pretty much this, thanks for the summary

348
I never knew that USB-C extensions are not allowed for a reason (www.youtube.com)
 

There is a reason for USB-C extensions not to be part of the standard. They can be bothersome in the best case and dangerous in the worst.

This little gadget to find out which type of USB-C cable you have in c/[email protected]
[–] [email protected] 2 points 3 months ago

I have one of those, it may pass as the great grandfather ;)

This little gadget to find out which type of USB-C cable you have in c/[email protected]
[–] [email protected] 1 points 3 months ago

They actually renamed the types which makes everything even more confusing

This little gadget to find out which type of USB-C cable you have in c/[email protected]
[–] [email protected] 2 points 3 months ago

Yeah, unfortunately fast data and fast charging are two independent characteristics...

This little gadget to find out which type of USB-C cable you have in c/[email protected]
[–] [email protected] 1 points 3 months ago

The thing is from Austria though?

349
This little gadget to find out which type of USB-C cable you have (discuss.tchncs.de)
 

cross-posted from: https://discuss.tchncs.de/post/22828099

USB was supposed to rule them all but it's now a mess of standards sharing the same connector. Different speeds, voltage, charging protocols, alt modes, even the number of pins used is variable.... For those asking, the thing is available on Kickstarter

This little gadget to find out which type of USB-C cable you have in c/[email protected]
[–] [email protected] 4 points 4 months ago (1 children)

Pretty much. I'm not even sure if regular USB ports can talk to pins individually, let alone test them for shorts.

This little gadget to find out which type of USB-C cable you have in c/[email protected]
[–] [email protected] 7 points 4 months ago (5 children)

Interesting, I just uploaded the .mp4 directly to lemmy and assumed this to be working. How else would you share a gif/short video?

180
This little gadget to find out which type of USB-C cable you have (discuss.tchncs.de)
submitted 4 months ago* (last edited 4 months ago) by [email protected] to c/[email protected]
25 comments fedilink
 

USB was supposed to rule them all but it's now a mess of standards sharing the same connector. Different speeds, voltage, charging protocols, alt modes, even the number of pins used is variable.... For those asking, the thing is available on Kickstarter

This tool for finding bad USB-C cables in c/[email protected]
[–] [email protected] 19 points 1 year ago (1 children)

Not sure what else, but the thing can tell you if a cable is USB2.0, USB3.0/3.1/.. or just for charging.

251
This tool for finding bad USB-C cables (hackaday.com)
 

EEVBlog also talked about this in a mailbag episode: https://www.youtube.com/watch?v=rEZQvSgdA2k&t=1839s

And they also have different cable versions available: https://caberqu.com/

Vintage Mac Community Begs Manufacturers for New Supply of Rare Dongle as Resellers Charge $250 in c/[email protected]
[–] [email protected] 14 points 1 year ago

I could design and produce a small batch of those adaptors.

Would anyone be interested in getting a prototype and helping to test it?

Shift register missing bits in c/[email protected]
[–] [email protected] 1 points 1 year ago

You're 100% right, I've lost 'i' somewhere in my debugging process

byte upper_byte = input_bin >> (8+i) ; byte lower_byte = (input_bin >> i) & 0x00FF;

Shift register missing bits in c/[email protected]
[–] [email protected] 2 points 1 year ago

Good idea, I've tried usleep after all lines, but no change..

13
Shift register missing bits (discuss.tchncs.de)
submitted 1 year ago* (last edited 1 year ago) by [email protected] to c/[email protected]
15 comments fedilink
 

Hey friends,

I have a two daisy chained shift registers (74AHC595) which are controlled via an ESP32. I want to set one output to high at a time before switching to the next.

The code seems to work, but the outputs O_9 and O_10 are not staying high (zoom) after setting them, whereas all the other ones are working fine. This is the used code snipped:

pinMode(SHIFT_OUT_DATA, OUTPUT);
pinMode(SHIFT_OUT_CLK, OUTPUT);
pinMode(SHIFT_OUT_N_EN, OUTPUT);
pinMode(SHIFT_OUT_LATCH, OUTPUT);

digitalWrite(SHIFT_OUT_N_EN, LOW);

uint16_t input_bin = 0b1000000000000000;

for(int i=0; i<17; i++){

    byte upper_byte = input_bin >> 8;
    byte lower_byte = input_bin & 0x00FF;

    digitalWrite(SHIFT_OUT_LATCH, LOW);
    shiftDataOut(SHIFT_OUT_DATA, SHIFT_OUT_CLK, MSBFIRST, lower_byte);
    shiftDataOut(SHIFT_OUT_DATA, SHIFT_OUT_CLK, MSBFIRST, upper_byte);
    usleep(10);
    digitalWrite(SHIFT_OUT_LATCH, HIGH);

    delay(10)
    input_bin = input_bin>>1;
}

Is there anything I'm doing wrong, or any idea on where the problem may lie? I've already tried looking for shorts and other error sources, but the design was manufactured on a PCB and no assembly issues are noticeable.

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