tag:blogger.com,1999:blog-20272332536697351682024-03-13T08:08:50.718+05:30NutsAndBoltsAndFlyingSparksTech blog, where I dump a few of my experiments with electronics, current projects and thoughts on things.Rohithttp://www.blogger.com/profile/00799585158210408114noreply@blogger.comBlogger31125tag:blogger.com,1999:blog-2027233253669735168.post-14589554803006583902023-05-30T17:08:00.001+05:302023-05-30T23:08:13.405+05:30Fixin’ a Glitchin’ ESP8266Fixin’ a Glitchin’ ESP8266 – or How to use two FNB58 as a Dual Channel Oscilloscope. So I’ve been using the ESP8266 for quite a while now within the confines of the Arduino environment. It’s been hobby stuff – playing with humidity and temperature sensors, making WiFi data loggers, controlling strings of addressable LEDs using the awesome WLED firmware, and quite a lot if other gimmicky stuff. Rohithttp://www.blogger.com/profile/00799585158210408114noreply@blogger.com0tag:blogger.com,1999:blog-2027233253669735168.post-44723203542668913972016-01-02T18:15:00.001+05:302016-01-02T18:26:31.594+05:30Eye-Oh-TeeI have finally jumped onto the IoT bandwagon, so this is a better-late-than-never kinda post. IoT – the Internet of Things, is a revolution of sorts. IoT devices promise to connect all devices to the internet. Check out any of today’s consumer electronic devices – thermometers, humidity sensors, power meters, which traditionally lend themselves well to such ‘internet-linking’, as well as Rohithttp://www.blogger.com/profile/00799585158210408114noreply@blogger.com0tag:blogger.com,1999:blog-2027233253669735168.post-61843680399356292522015-09-23T13:46:00.001+05:302015-09-23T15:18:13.745+05:30Look Ma, No Wires!I’m blogging after aeons! Been really busy; work is such :-/ It’s not like I haven’t been tinkering at all, it’s just that I’ve been tinkering less, and haven’t had the time to document it. A few weeks ago I decided that I needed a Bluetooth-to-audio adapter for my home (which has a decent but dated Sony home theatre) and car (which has an old stereo system). So this vacation I decided to make Rohithttp://www.blogger.com/profile/00799585158210408114noreply@blogger.com1tag:blogger.com,1999:blog-2027233253669735168.post-19797565166475658772012-07-11T00:45:00.001+05:302012-07-14T15:35:26.149+05:30I Got Spinners Dawg!I am an engineer. By profession, by hobby and therefore, by passion. And being an engineer requires me to browse through PDFs several pages long, or plow through code confusing enough to make your eyes pop out. I may do this just to look cool, but all the same, I have to do it. Using a mouse scroll wheel with its annoying ‘click’ makes my index finger sore pretty quick. So then I switch to my Rohithttp://www.blogger.com/profile/00799585158210408114noreply@blogger.com7tag:blogger.com,1999:blog-2027233253669735168.post-5072145755004275832012-07-03T23:46:00.001+05:302012-07-10T22:12:21.667+05:30USB OTG on a Sony Live With WalkmanI have a nice Android phone – the Sony Live With Walkman, affectionately called the ‘LWW’. The phone specs state that it has USB OTG – USB On-the-Go. OTG is a funky specification that allows phones (and other devices) to act both as a slave (so you can connect it to your computer an use it as external storage) or as a host. The host mode potentially enables you to use mice, keyboards, USB flash Rohithttp://www.blogger.com/profile/00799585158210408114noreply@blogger.com33tag:blogger.com,1999:blog-2027233253669735168.post-63347103233500497992011-12-04T19:27:00.001+05:302011-12-05T07:47:07.209+05:30Rescuing an ArduinoBT boardA few days ago I help a friend recover his ArduinoBT board. He had somehow managed to mess up the Bluetooth bootloader on the Arduino, and with wireless comms being the only way to program the board, he was stuck. I used my DIY BP BusPirate along with the STK500 firmware found on DangerousPrototype’s website to reflash the ATmega328 on the board. The process was reasonably straightforward as you Rohithttp://www.blogger.com/profile/00799585158210408114noreply@blogger.com0tag:blogger.com,1999:blog-2027233253669735168.post-25638569761695084282011-07-10T23:08:00.001+05:302011-07-10T23:08:32.969+05:30Reflow SolderingI’ve been working with SMDs for quite some time now. Upto now I’ve been using a magnifying glass, a point tip, fine solder, and copious amounts of flux, but when you’ve got a bunch of chips with tiny little pins (or maybe even NO pins!) reflow soldering is the way to go. Very tiny balls of solder suspended in flux form a sort of paste. This solder paste is applied to the pads over which the chipRohithttp://www.blogger.com/profile/00799585158210408114noreply@blogger.com3tag:blogger.com,1999:blog-2027233253669735168.post-83388576119120335652011-07-03T08:01:00.001+05:302011-07-03T08:01:55.676+05:30Electronics makes the summers a happy time!Two orders arriving in a span of less than three days! It’s almost as good as Christmas! I bought some stuff from iTead Studio. It came decently packed in a small cardboard box. The components were sealed in static resistant bags, and then wrapped in bubble wrap. So everything came safe. My haul from iTead I bought a waterproof ultrasonic sensor, two nRF24L01+ 2.4GHz radios, a regular Rohithttp://www.blogger.com/profile/00799585158210408114noreply@blogger.com0tag:blogger.com,1999:blog-2027233253669735168.post-30531637386410534422011-06-30T17:28:00.001+05:302011-07-02T07:44:36.264+05:30Arr me hearties! Meet me ol’ Bus Pirate!Those of you who are acquainted with my eccentric mannerisms must know that I rarely throw junk out, more so if it is electronic scrap. Old electronics are perfect places to find serial memory chips and audio amplifiers and digital logic gates and motor drivers. Sometimes (well, actually most times) the chips have vague numbers and markings, or even no numbers (so as to protect the manufacturer’sRohithttp://www.blogger.com/profile/00799585158210408114noreply@blogger.com0tag:blogger.com,1999:blog-2027233253669735168.post-59169660135367745112011-06-25T17:15:00.000+05:302011-06-25T17:26:15.245+05:30Using the BU2090FS LED shift driverI do a lot of scavenging for components. Whenever I get my hands on junk electronics I whip out my soldering iron, a desoldering pump, some pliers, and a pair of tweezers to see what I can extract from it. Scavenging is a long, tedious and sometimes painful process involving singed hair and burnt fingers, but every once in a while I come across a really nice component from an old TV or washing Rohithttp://www.blogger.com/profile/00799585158210408114noreply@blogger.com2tag:blogger.com,1999:blog-2027233253669735168.post-83598741014951256132011-06-18T00:31:00.001+05:302011-06-18T09:47:58.774+05:30Cheap Graphics – Nokia 3310 LCDIt’s been aeons since I blogged last. I’ve kinda gotten rusty so I thought I’d begin small by blogging about something that’s been a work-in-progress for a quite a while. I’m always looking for inexpensive ways to add ‘bling’ to my projects. A graphic LCD is a lovely way to add that extra bit of fun (and functionality) to an application. Granted, a graphical display may be total overkill in someRohithttp://www.blogger.com/profile/00799585158210408114noreply@blogger.com1tag:blogger.com,1999:blog-2027233253669735168.post-6042255873367515822010-07-08T10:27:00.001+05:302011-01-17T19:01:59.199+05:30Hacking the Wii MotionPlusSo its been two days since I got my Nintendo Wii MotionPlus (henceforth simply ‘WM+’; yeah, I know I called it the ‘M+’ earlier :-|) clone from DealExtreme. And I’ve been itching to get some data off it. The WM+ uses I2C to send and receive data from a host, which is normally a WiiMote, but in my case it is a PIC16F877. The hacked WM+. I desoldered the pass-through port (normally used to Rohithttp://www.blogger.com/profile/00799585158210408114noreply@blogger.com3tag:blogger.com,1999:blog-2027233253669735168.post-22695000562041979842010-07-05T15:20:00.001+05:302010-07-07T13:59:32.623+05:30I Love the MailmanI think certain clarifications are in order - I am completely heterosexual; its just that today, one of the mailmen brought me a few parcels, which I have been eagerly waiting for. One of those parcels was a Sensiron SDP610 sample, which is a CMOS differential pressure sensor; the other parcel is the subject of this blog.   Left: The Sensirion SDP610 differential pressure sensor Rohithttp://www.blogger.com/profile/00799585158210408114noreply@blogger.com0tag:blogger.com,1999:blog-2027233253669735168.post-25937879775025712252010-07-01T19:37:00.001+05:302010-07-01T19:37:07.989+05:30No Strings (or Wires), AttachedIt’s been a while since I’ve blogged. Its not like I haven’t been trying – my drafts pane in Windows Live Writer is full of half-finished posts. Maybe I’ll complete them and post them before the summer ends. Or maybe not. This post is about using those cheap 300-bucks-a-pair modules. For international readers, INR300~USD6. If you look around where you live you’ll find the same or similar modulesRohithttp://www.blogger.com/profile/00799585158210408114noreply@blogger.com3tag:blogger.com,1999:blog-2027233253669735168.post-6660284173522945162010-02-16T17:23:00.001+05:302010-02-16T17:23:01.179+05:30Touch Me Please: VideoYou can watch the video of my touchpad interface here: The touchpad is taken from an HP Pavilion dv2000 laptop. A PIC16F628A performs all the necessary PS/2 host functions; and a Nokia 3310 LCD is used to display ‘mouse’ movement. The LCD uses custom graphics. I wrote both, the LCD driver, and the firmware to run the touchpad. Code is in CCS-C. Both drivers are based on info found online. Do Rohithttp://www.blogger.com/profile/00799585158210408114noreply@blogger.com7tag:blogger.com,1999:blog-2027233253669735168.post-65151300535659921832010-02-14T19:05:00.001+05:302010-02-15T12:23:18.469+05:30Touch Me Please!Before I dive into this post I take a moment to profusely apologize for the title of the post – it is tragically horrendous. OK, so now that I’ve got that out of the way, lemme begin. This post is a little out of ‘order’; it would have been more appropriate had I first blogged about how I procured some of the components mentioned in this post. But heck! Lazy as I am, I guess I’ll leave that for Rohithttp://www.blogger.com/profile/00799585158210408114noreply@blogger.com3tag:blogger.com,1999:blog-2027233253669735168.post-64492662801914227042010-01-28T18:14:00.001+05:302010-01-28T18:14:26.369+05:30Update: Main(s) is a PainHere’s a quick update: remember I said in my original post on powerline networking that the reason why I wasn’t getting a clean sinusoidal wave on the transformer was probably due to the fact that the duty cycle of the PWM signal generated by the PIC’s CCP was not 50%? Turns out I was right. I set the duty to exactly 50% and though I not getting a sine wave even now, its still pretty close. In Rohithttp://www.blogger.com/profile/00799585158210408114noreply@blogger.com1tag:blogger.com,1999:blog-2027233253669735168.post-28690169745257319712010-01-26T15:04:00.003+05:302010-03-31T11:00:06.116+05:30Main(s) is a PainNOTE: Windows Live Write S*CKS! WYSINWYG (what you see is NOT what you get). I used to type out something, and land up with some completely vague formatting! It took me a while to fix this. * * * * * * * * * * * * Now who would have thought that the powerline would be fraught with difficulties such as these – from an imbalanced phase to noisy EMI it all just seems Rohithttp://www.blogger.com/profile/00799585158210408114noreply@blogger.com3tag:blogger.com,1999:blog-2027233253669735168.post-60689478146651187522010-01-15T20:23:00.003+05:302010-01-16T01:04:46.414+05:30My First ‘Proper’ T&M InstrumentI haven’t written in AEONS! And I figured, “Hey! What better way to begin my two-zero-one-zero archive than by bragging…..oops!….I mean blogging about one of my new acquisitions”. I’ve recently bought myself a DSO. Not the fancy Agilent or Tektronix scopes; I bought myself something much more affordable – a DSO2090. I’m pleased with it. Very pleased. And, since there are very few reviews about itRohithttp://www.blogger.com/profile/00799585158210408114noreply@blogger.com4tag:blogger.com,1999:blog-2027233253669735168.post-42384032729228986432009-10-14T17:28:00.001+05:302009-10-17T01:18:37.621+05:30Scrounging Around…….This post is similar to one I had made on BITS 360 a while back. Having finished my Bachelor’s degree from BITS-Goa, I’ve now transferred to the Pilani Campus. So this is my first post after coming to Pilani. As was in Goa, here too several ‘poor’ students (a point to note is that the word ‘poor’ refers to the usual scarcity of money that college students, being college students, face, and not Rohithttp://www.blogger.com/profile/00799585158210408114noreply@blogger.com0tag:blogger.com,1999:blog-2027233253669735168.post-36423481313033558492009-07-05T10:14:00.001+05:302009-07-05T10:16:24.418+05:30To DoIf I remember correctly, my first introduction to circuits was in my 4th grade when my dad’s friend gave me a neat science-projects like kit. The kit contained components to teach the basics of electronics - switches, a buzzer, small incandescent bulbs (I absolutely dislike using these bulbs nowadays because of the power they drain), wires, steel wool, and other such things. I was in the US at Rohithttp://www.blogger.com/profile/00799585158210408114noreply@blogger.com7tag:blogger.com,1999:blog-2027233253669735168.post-76618591901378635292009-07-03T15:57:00.001+05:302009-07-03T16:09:29.521+05:30The Super ProbeI remember mentioning in one of my earlier posts that an Oscilloscope was very high on my wish-list. The other day I entered into a bidding war on eBay-USA for a no-name DSO. It was pretty inexpensive, and the features it had seemed reasonably good. Sadly, I was outdone by some chap from Germany, who was willing to pay more than four times the amount I was. After the eBay misadventure, my Rohithttp://www.blogger.com/profile/00799585158210408114noreply@blogger.com4tag:blogger.com,1999:blog-2027233253669735168.post-66502793975187711732009-05-28T16:37:00.004+05:302009-05-28T19:34:13.574+05:30Tripping Up?About two years ago one of my best friends (I’ve known him since the 9th grade in school, and we were in JHC, A-Div together) gifted me a Griffin iTrip. He had just recently bought (been gifted?) an iPod video, and the iTrip 4014 was not compatible with it. Not wanting to throw the iTrip out, he very sweetly gave it to me (thanks bro!). Incidentally, I happened to be the second in our ‘gang’ to Rohithttp://www.blogger.com/profile/00799585158210408114noreply@blogger.com1tag:blogger.com,1999:blog-2027233253669735168.post-55182928641749390312009-05-27T15:35:00.004+05:302009-05-28T19:26:39.607+05:30After the Long Break<!--[if gte mso 9]> Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 <![endif]--><!--[if gte mso 9]>Rohithttp://www.blogger.com/profile/00799585158210408114noreply@blogger.com6tag:blogger.com,1999:blog-2027233253669735168.post-57594395902136322012008-12-16T18:14:00.014+05:302008-12-18T09:51:47.930+05:30Switching Regulators, Boost Converters and The IBM ChargerA friend of mine (it would not be right to continue this post without a mention of her) recently gave me her busted IBM Thinkpad charger. Vidya (or nVidiya as I like to call her) said “Do what you want with it, and if you put it to good use, do tell”. The best resting grounds I can think of for damaged things is my desk, where these otherwise never-again-to-be-used-by-mankind objects serve one Rohithttp://www.blogger.com/profile/00799585158210408114noreply@blogger.com2