Electrical Engineering V3 - Developers

okay nvm turns out we have a Zync Ultrascale+EG, which has this layout: [t]https://www.xilinx.com/content/dam/xilinx/imgs/products/zynq/zynq-eg-block.PNG[/t] So since we have SDR guys that are experts in this stuff, and since part of being PI on an SBIR topic is knowing who to seek out for help (I can't bring myself to think of the fact that I'd be PI and they'd be "reporting ot me"...), I'll be playing with this. We don't have any immediate usage for it atm, and I'm betting I could just write an abstraction layer over one of these things that involves writing different accelerator modules to the HUGE programmable logic on this, or decides to run on the GPU onboard if it can. I'll be interested to test it more In the mean time, I've got to learn VHDL :nope: [editline]15th December 2016[/editline] 256k logic cells though, iirc [editline]15th December 2016[/editline] it was a $2600 whim purchase by one of our software guys lol

Christ that is a dense SoC. VHDL isn't that bad provided that you get in the mindset that despite its familiar C-like syntax and organization its all behavioural instead of instructional (i.e. everything is simultaneous behaviours and relationships instead of a list of instructions to be executed).

Bought some cheapass Welleman butane soldering iron for when doing wiring repairs in cars and there's too far to a mains socket. Turns out it can also be used as a hot-air iron for smaller SMD components or shrink-wrap. You can forget anything about precise temperature adjustment though, but I actually got the hang of it while desoldering the flash IC on a ESP8266 board. Biggest beef I have with it is lack of piezo igniter, but hey, was cheap.

Made the hardware for a prototype controller for a platform called "MeWe Space". [img]http://i.imgur.com/1mPOMv9.png[/img] [img]http://i.imgur.com/75xarYw.jpg[/img] [img]http://i.imgur.com/kEf9jrw.jpg[/img] Took some time to solder :-) - Inside is a Raspberry Pi and a 9-dof module.

All I wanted for christmas was a hot air rework station. Plus pants. Pants are nice. I got both. :D [editline]asdsa[/editline] Wow this is actually really nice given it's a cloned reference design. I can desolder SMD DIP's with the air and heat set on half with the small nozzle.

Is it safe to assume that the following pin-out: [t]http://s30.postimg.org/t6pepdldt/esp8266_flash_IC.png[/t] is true for almost all 8-pin DIP SPI IC's? Because I got a SMD SOIC clip that I need to solder some wires onto since it uses 2mm pin spacing, and it seems like the two SPI IC use cases I will be dabbling with primarily at the moment (BIOS IC on xx30 series Thinkpads, and ESP-8266/ESP-32 modules) all use that pin-out. So if that [B]REALLY[/B] is a [I]not-officially-a-standard-but-let's-treat-it-as-such[/I] pin-out then I can color code the wires and mark the clip to make it easier for me to work with.

How I spend my lunch breaks. :v: [video=youtube;5spYO3jjQ8o]http://www.youtube.com/watch?v=5spYO3jjQ8o[/video]

Okay guys, relative idiot here when it comes to circuitry. I know how to solder and how an LED and resistors and relays work, but that's about it. I know nothing of voltage regulation, amplification, or step down. I've got a Surface Pro, and a portable battery bank with two 2.1A USB ports on it. The Surface takes 12v 3.6A. How do I make those two USB ports into power I can use to charge my Surface?

[QUOTE=Trekintosh;51640985]Okay guys, relative idiot here when it comes to circuitry. I know how to solder and how an LED and resistors and relays work, but that's about it. I know nothing of voltage regulation, amplification, or step down. I've got a Surface Pro, and a portable battery bank with two 2.1A USB ports on it. The Surface takes 12v 3.6A. How do I make those two USB ports into power I can use to charge my Surface?[/QUOTE] First question is if that power bank can supply 2.1A separately to both ports or 2.1A total across both ports. If its the later than you might not be able to charge your laptop. [URL="https://www.amazon.com/DROK-Converter-Adjustable-Regulator-Transformer/dp/B00UR5K4AE/ref=pd_sim_23_2?_encoding=UTF8&refRID=YZ3HKP3NDRN9R60K7YDB&th=1"]You can buy voltage booster modules that really only require a small screwdriver for wiring and tuning[/URL], and then at that point the only limiting factor is the power bank itself. Its hard to tell how it'll handle, so I'd recommend putting your computer to sleep or shutting it down and try some test charges to see how it'll handle. Edit: [URL="https://www.youtube.com/watch?v=QKUSFQu96BI"]Of course some one has already solved this.[/URL] :tinfoil:

[t]http://i.imgur.com/F1dEIDE.jpg[/t] Whoever this...freak...is they have terrible furnishing tastes. I mean, that tablecloth with those curtains? Gross. Oh yeah, nice source sync unit.

[QUOTE=LoneWolf_Recon;51641339]First question is if that power bank can supply 2.1A separately to both ports or 2.1A total across both ports. If its the later than you might not be able to charge your laptop. [URL="https://www.amazon.com/DROK-Converter-Adjustable-Regulator-Transformer/dp/B00UR5K4AE/ref=pd_sim_23_2?_encoding=UTF8&refRID=YZ3HKP3NDRN9R60K7YDB&th=1"]You can buy voltage booster modules that really only require a small screwdriver for wiring and tuning[/URL], and then at that point the only limiting factor is the power bank itself. Its hard to tell how it'll handle, so I'd recommend putting your computer to sleep or shutting it down and try some test charges to see how it'll handle. Edit: [URL="https://www.youtube.com/watch?v=QKUSFQu96BI"]Of course some one has already solved this.[/URL] :tinfoil:[/QUOTE] Yes, it does supply 2.1A to each port, meaning 4.2A total. That booster looks perfect. My next question is do I run the ports with a parallel Y cable or in series? And how do I limit the output current of the booster?

[QUOTE=Trekintosh;51641754]Yes, it does supply 2.1A to each port, meaning 4.2A total. That booster looks perfect. My next question is do I run the ports with a parallel Y cable or in series? And how do I limit the output current of the booster?[/QUOTE] Keep in mind that that booster can supply up to 6A output current, not force 6A. However if you are worried about shorts you could feasibly get a 5A fuse (Usually such boosters have a thermal shutdown or current limiter, but it never hurts to have a fuse). You'll have to make some sort of parallel Y-cable but keep in mind that you'll need to put a schottky diode (That can support atleast 2.1A continuous current such as a [URL="https://www.amazon.com/SUNKEE-Rectifier-1N4148-1N4007-1N5819/dp/B00AWM3UY4/ref=sr_1_1?ie=UTF8&qid=1483912181&sr=8-1&keywords=1N5822"]1N5822[/URL]) on each 5V out of the USB port ([URL="http://www.proflow.ca/wp-content/uploads/2013/05/redundant_power_supplies_with_oring_diodes.gif"]like so[/URL]) so that you don't backfeed each USB port as they're probably on separate voltage regulators. I'd honestly recommend starting to see if you can charge from just a single USB port directly feed into the boost converter. Usually the laptop is smart enough to limit its own charge current (especially in sleep/powered-off modes) when it detects a drop in input voltage.

I'd crack open the power bank and check if it even has separate voltage regulators for each USB port, or it just hammers out 4.2 or 5 Ampere and the USB ports have polyfuses. But some powerbanks are a royal bitch to open without damaging.

[QUOTE=LoneWolf_Recon;51641867]Keep in mind that that booster can supply up to 6A output current, not force 6A. However if you are worried about shorts you could feasibly get a 5A fuse (Usually such boosters have a thermal shutdown or current limiter, but it never hurts to have a fuse). You'll have to make some sort of parallel Y-cable but keep in mind that you'll need to put a schottky diode (That can support atleast 2.1A continuous current such as a [URL=https://www.amazon.com/SUNKEE-Rectifier-1N4148-1N4007-1N5819/dp/B00AWM3UY4/ref=sr_1_1?ie=UTF8&qid=1483912181&sr=8-1&keywords=1N5822]1N5822[/URL]) on each 5V out of the USB port ([URL="http://www.proflow.ca/wp-content/uploads/2013/05/redundant_power_supplies_with_oring_diodes.gif"]like so[/URL]) so that you don't backfeed each USB port as they're probably on separate voltage regulators. I'd honestly recommend starting to see if you can charge from just a single USB port directly feed into the boost converter. Usually the laptop is smart enough to limit its own charge current (especially in sleep/powered-off modes) when it detects a drop in input voltage.[/QUOTE] I was going to order one of [url=StarTech.com USB2HABMY1 1 Feet USB Y Cable for External Hard Drive - USB A to mini B [url=https://www.amazon.com/dp/B003WV5DMO/ref=cm_sw_r_cp_api_sDTCyb06W4Q98]these Y cables[/url] and hack the end off, or use a USB breakout or something for it. I've already got one of these so if I can get a mini B female breakout that makes my job easier. About the current, I was referring to how the USB ports would put out 4.2A combined, while the Surface takes 3.6. I don't want to damage the machine. However, I suppose the booster losses will compensate for that. [editline]8th January 2017[/editline] [QUOTE=Van-man;51641953]I'd crack open the power bank and check if it even has separate voltage regulators for each USB port, or it just hammers out 4.2 or 5 Ampere and the USB ports have polyfuses. But some powerbanks are a royal bitch to open without damaging.[/QUOTE] It's a high quality iMuto 20,000mah power bank, I can't imagine it having a single regulator. Plus it has so-called intelligent charging on a per port basis. That makes me think it'll be more likely to have separate controllers.

[QUOTE=Trekintosh;51642594]I was going to order one of [url=StarTech.com USB2HABMY1 1 Feet USB Y Cable for External Hard Drive - USB A to mini B [url=https://www.amazon.com/dp/B003WV5DMO/ref=cm_sw_r_cp_api_sDTCyb06W4Q98]these Y cables[/url] and hack the end off, or use a USB breakout or something for it. I've already got one of these so if I can get a mini B female breakout that makes my job easier. About the current, I was referring to how the USB ports would put out 4.2A combined, while the Surface takes 3.6. I don't want to damage the machine. However, I suppose the booster losses will compensate for that. [editline]8th January 2017[/editline] It's a high quality iMuto 20,000mah power bank, I can't imagine it having a single regulator. Plus it has so-called intelligent charging on a per port basis. That makes me think it'll be more likely to have separate controllers.[/QUOTE] However, none of these actually force xAmps, they just are able to supply [U]up to[/U] xAmps. Thus together both USB ports will have enough current to theoretically power your laptop and a little bit extra for booster looses. Also dead link on the cable.

[QUOTE=LoneWolf_Recon;51642945]However, none of these actually force xAmps, they just are able to supply [U]up to[/U] xAmps. Thus together both USB ports will have enough current to theoretically power your laptop and a little bit extra for booster looses. Also dead link on the cable.[/QUOTE] Sorry. I spent five minutes fighting with it and must have screwed up. [url]https://www.amazon.com/dp/B003WV5DMO/ref=cm_sw_r_cp_api_QPWCybBKRNQFQ[/url]

[QUOTE=Trekintosh;51642594]I was going to order one of [URL="http://StarTech.com USB2HABMY1 1 Feet USB Y Cable for External Hard Drive - USB A to mini B [url=https://www.amazon.com/dp/B003WV5DMO/ref=cm_sw_r_cp_api_sDTCyb06W4Q98"]these Y cables[/URL] and hack the end off, or use a USB breakout or something for it. I've already got one of these so if I can get a mini B female breakout that makes my job easier. About the current, I was referring to how the USB ports would put out 4.2A combined, while the Surface takes 3.6. I don't want to damage the machine. However, I suppose the booster losses will compensate for that. [/QUOTE] Uhm, you'll not get 4.2A at 12V. 4.2A at 5V is 1.75A at 12V (Without accounting for losses), you will probably not be able to charge the battery but maybe extend the battery life. And you could have a 1000A power supply at 12V, the Surface would still only grab whatever it'll need.

[video=youtube;CImyDBJSTsQ]http://www.youtube.com/watch?v=CImyDBJSTsQ[/video] Man, its talks like these that I wish I could go abroad just to attend CCC.

[QUOTE=LoneWolf_Recon;51678352] Man, its talks like these that I wish I could go abroad just to attend CCC.[/QUOTE] I saw it live, being there makes a talk so much better

[QUOTE=DrDevil;51679152]I saw it live, being there makes a talk so much better[/QUOTE] Besides all the talks, what else goes on? I've felt like they have CTF events and/or some sort of maker faire as well.

[QUOTE=LoneWolf_Recon;51679489]Besides all the talks, what else goes on? I've felt like they have CTF events and/or some sort of maker faire as well.[/QUOTE] I mostly use the chance to meet people I know from the internet, including some facepunchers. Many people present their projects there, but it's not like a maker faire. There was a CTF going on, but I kinda missed it. [editline]16th January 2017[/editline] Oh, I also smoked loadsa weed in the kickass lounge.

Alright guys, here's a fun one. I have a cable harness here for a camera. It was damaged when the camera took a nasty fall, breaking one wire and barring up the insulation on others. [IMG]http://i11.photobucket.com/albums/a166/ballsandy/New%20Bucket/IMG_6859.jpg[/IMG] Wire diameter is 0.3mm (stranded). How would I be able to reinsulate the splices once finished? I'm not aware of shrink tube that small.

[URL="https://www.amazon.com/Gardner-Bender-LTB-400-Liquid-Electrical/dp/B000FPAN2K"]Liquid Electrical Tape[/URL], a toothpick and a steady hand.

Just put the smallest shrinkwrap you can find on it, then try to put shrinkwrap over the connector. There is some shrinkwrap with ridiculous shrinking ratios, so you should be able to get one barely over it.

I remember several years ago I had tried to desolder a cap from a motherboard with my shitty fixed temperature iron and failed miserably. How things have changed for me: [img]http://i.imgur.com/UZagcuyl.jpg[/img] I've got some plans to stuff this into a fairly cramped enclosure so I had to remove anything too tall. I know they make thin ITX motherboards but I need the PCI-E slot for a GTX 1050 which will also be jammed alongside with it.

Finally got off my ass and back to work finishing my tube amp. [img]http://i.imgur.com/D52oUAg.jpg[/img] What's funny ? it's quality construction compared with my usual stuff :v:

Power management problem: I've been planning to make a LED strip backlight on my wall, involving about 420 WS2812B leds which run on 5V. [URL="https://learn.adafruit.com/adafruit-neopixel-uberguide/power"]Each led at maximum brightness draws about 60 mA.[/URL] Which would mean I'd need a power supply of atleast 25 Amps. Would chinese power supplies like[URL="https://www.aliexpress.com/item/5V-2A-3A-4A-5A-8A-10A-12A-20A-30A-40A-60A-Switch-LED-Power-Supply/32670505021.html?ws_ab_test=searchweb0_0,searchweb201602_1_10065_10068_10000032_119_10000025_10000029_430_10000028_10060_10062_10056_10055_10000062_10054_10059_10099_10000022_10000012_10103_10000015_10102_10096_10000018_10000019_10000056_10000059_10052_10053_10107_10050_10106_10051_10000053_10000007_10000050_10084_10118_10083_10000047_10080_10082_10081_10110_10111_10112_10113_10114_10115_10037_10000041_10000044_10078_10079_10077_10000038_429_10073_10000035_10121-10051_119,searchweb201603_1,afswitch_1,single_sort_3_default&btsid=8e06dc64-9246-4593-8ab6-35f6e99ef818"] these ones [/URL] be reliable enough if I take a big enough margin (for example a 40A supply)? If they aren't, what is a good place to find beefy power supplies? I don't really know where to search to stuff similair to what I linked. I don't want to light shit on fire if possible :v:

Keep in mind that you need to feed in the 5V at more than one point (for example every 3 meters or so), or else the voltage will drop too much over the strip. Especially at 25 amps. Additionally you could limit the cumulative brightness to something like 50% in software. Then you don't need to spec it for full power. 50% can be more than enough if you don't plan to use it as white light, which I don't recommend at all.

[QUOTE=DrDevil;51761159]Keep in mind that you need to feed in the 5V at more than one point (for example every 3 meters or so), or else the voltage will drop too much over the strip. Especially at 25 amps. Additionally you could limit the cumulative brightness to something like 50% in software. Then you don't need to spec it for full power. 50% can be more than enough if you don't plan to use it as white light, which I don't recommend at all.[/QUOTE] There's WS2812B clones that also includes a white LED, but they're slightly different protocol-wise.

it's 4 strips each of 1.75 meter all connected to a central hub, so the voltage drop across each strip shouldn't be too big of an issue. I don't plan on running them at full brightness or close to right now, but it might happen in the future.