I really thought i'd be updating this blog more often, but apparently a PhD involves work?! Also, i don't know how much i should be disclosing about my project over the internet. Not that i'm working on something top secret or anything, i just don't know the procedure. I will say that at the moment i'm wracking my brain trying to get a simulink model working. Yes, this is the same model i mentioned in my last post...it's a big model. I'm also trying to get to grips with this program called Coventorware as well as keeping up my reading.
This weekend i was in the office doing some work when myself and Feras decided to give "left 4 dead 2" a try (demo version on steam). Seriously, this game is fun! We played the same demo level over and over, and while that seems sad, it was actually good craic. I'm thinking of asking for it for christmas, but that seems too far away. I want it now! We're thinking of making Saturday a regular gaming night since we pretty much have the office to ourselves.
Last week i tried out the "Tropico 3" demo. All i have to say is "meh". It's alright but i wouldn't rush out and buy it. I seem to be moving away from the easy going simulation/adventure games towards first person shooters and RPGs. Speaking of which, is anyone else incredibly excited about Mass Effect 2 coming out soon? I'll have to fix my PC so i can get the old saved game off it and put it on my new mega pc.
On another note, in 4 weeks I'll be back in Ireland! Oh, watch this, i thought it was hilarious:
Right, i was meant to update this like 2 weeks ago, but i'm easily sidetracked.
It's actually 3pm on a Saturday afternoon while i'm typing this and i'm at my desk in the office trying to get a transverse capacitor model up and running on Simulink. Sad much? To be fair though, i haven't spent that much time this week in the office working since there are still a few compulsory induction events i've had to attend. I'm just trying to make up for a bit of lost time.
I only picked a definite PhD title last week. When i originally met my supervisor he gave me 3 topics to choose from. Two of them were a bit too deep in physics for me so i chose the one that was a bit more in my comfort zone. I'm really happy with my choice and am actually excited about doing work on it. I have been realising lately how luck i am to actually be studying here at Southampton. Regardless of the fact that i don't have any funding, it really pays for itself. The equipment in this University is insane. The new building, where my desk is, cost £100 million pounds to build and fill with state of the art equipment and it's just so cool. Also, the computer that they gave me for my desk is the highest spec machine i've ever seen, and i have 2 22" samsung monitors attached to it. So yeah, i'm really lucky.
For this semester, i'm sitting in on 2 modules, just to get myself up to speed on the basics of the technology i'll be using. I'm taking "Introduction to MEMs" and "Microfabrication". The MEMs course is interesting but i've been reading a great book at home called "Micromachined Transducer Sourcebook" which contains essentially the same information as the course, still though, it's good to have a lecturer to explain it better. I haven't attended a Mircofabrication lecture yet because i couldn't find the building this week. The layout of the campus is pretty confusing and it's extremely frustrating when you can't find a building and have been walking around for 30 minutes trying to find it.
Well, i'm going to go get myself a hot chocolate from the machine and get back to work. I'll try update again soon.
So it's been a while but now the summer is drawing to a close and i'm starting back to University so this blog will get updated on a more regular basis.
I'm writing this post from my room in Southampton! I arrived here yesterday with my parents. I am living in Halls accomodation which are much nicer than i was expecting. I'm meant to be sharing this flat with 6 other people but so far i've only met 3. I don't think the others have moved in yet.
On Thursday (1st October) i'm meant to be heading into the college for a kind of induction. Until then, i might head into the college to check out freshers week. Today i went into town with my one of my flatmates to buy a few bits and pieces for the kitchen. I picked up a 3 sim card for my phone.
During the next few days i'll also have to start reading my supervisors publications. Or perhaps i'll wander into the libraries and read up on Mems devices. I'll update on thursday with how induction went.
Okay this is a very quick update because i'm really tired and want to go to bed soon.
On the 22nd the exam results were released. I got my 2:1 so i was happy, although, not as happy as i thought i'd be. I felt like i could have done better in certain areas. Everything felt slightly anti-climactic. So much so, that i almost felt depressed by it. This soon went away anyway, i guess the shock of being finished subsided and instead i realised that i had a world of opportunity in front of me.
Then to make things even better, a few days later i recieved an email from Southampton University offering me a place to study with Professor Kraft in the Nanoscale Integration department of the college for a PhD!!! This is huge! Obviously if you've been reading previous posts, you'll know that Southampton was the dream. It's the best college to go for Electronic Engineering study. I'll find out in roughly 2 weeks whether or not i have funding to accompany this but i'm not going to get my hopes up about that...that would be way too much good fortune to process.
I'm leaving for Rock Werchter on thursday morning. My flight is really early so i'm staying the night before with my sister. I've been watching Glastonbury on the tv and getting really psyched up for Werchter now. When i come back from Belgium i'll have to start planning my move to Southampton, oh and i'm taking sailing lessons with my dad too. The next few weeks should be pretty busy, but i'll try keep this updated.
Bed time now..this wasn't as short as i had intented.
Time for an update me thinks. Since i have finished my exams i have moved out of Limerick and back home to Clonmel. I had no means of supporting myself in Limerick and even though i was initally sad to leave, i'm now used to being back home. I had to clear out the "junk room" to claim a bedroom, but now it's homely.
On Thursday i got back from a short trip to Hamburg. I went to visit a friend who's there on erasamus. It was a nice break but on the last day i was pretty hungover and had 12 hours of travel ahead of me to get home. Now that i'm back i have Werchter to look forward to, which is on in roughly 10 days. I'm actually freaking out a small bit because i had no idea it was so close.
Tomorrow i'm heading up to Dublin with my family to celebrate my sister's birth. I'm not sure what we're doing but hopefully it'll be a good day. The exam/degree results are then out on Monday... dun dun dun! Alot of friends in other colleges have already gotten their results and have done extremely well. I'm so scared that i have done badly. I need to get my 2.1! I have a backup plan, but i don't want to have to resort to it. I got an email from Southampton during the week to say that they have a PhD studenship available but need to know my degree results before i'm able to be considered for it. I NEED THIS!!!
So fingers crossed everyone. In 2 days my future will be decided.
I am half way through my exams at the moment. I have 2 more left and one of those is tomorrow. So far i dont know how i'm doing, Control2 was difficult and VLSI was grand. I'm dreading tomorrows exam (telecommunications). I really hate having to learn about all this vector encoding crap and how it applies to the OSI network model. I have zero interest in any job involving telecommunications, if i did, i'd have done a different course or would have stuck with Computer Engineering instead of switching to Electronic.
My ranting will get me nowhere though. Like it or not i have to sit this exam tomorrow. I'm not sure what the structure will be like, but if it resembles last year (MCQs followed by long questions) i'll be okay. It's not on until 4pm anyway so i can do some last minute cramming. Then on Saturday i have my final exam which is ASICS2. This should be okay. I'm the only person in the class so i feel this extra responsibility to do well. The exam paper is really interesting though, like there's a design question based on a HSPICE file, and you have to determine all the steady state currents and voltages based on this file.
While all my exams are finished on Saturday, i won't have anytime for celebrating as i still have to finish my Sigma Delta Modulator design. I have the basic hardware laid out. I'm concerned about the latched comparator part. Basically i wasn't sure how to design a latched comparator when i have a PMOS differential pair in my comparator, so i just put a latch on the output...as in 4 NAND gates. It's really inefficient so if there's anyone reading this and knows how to design a latched comparator, please send it to me.
I need to finish this project by Monday. Then i'll be free to enjoy the Breeders which i'm going to on Monday night. I have 4 days of hardship ahead.
My first exam is in 2 days, but i'm not going to write about that. As a method of procrastination i've been playing my guitar ALOT! I'm thinking i might post some videos of stuff i'm working on, but i don't know. Does anyone even read this? This summer i'm moving back home to Clonmel and i think i'll move my drum kit from my Dad's Limerick office unit to the Clonmel one, if he'll allow it. I've got big plans for this summer, not just in regards to music, but for everything. Anything i've ever wanted to change about myself, i'm going to try and do it.
This day 2 weeks, i'll be at the Breeders gig in Dublin. The next 2 weeks are going to be tough, i'm freaking out a bit actually. I always get so stressed out around exam time but it gets exponentially worse as the semesters get harder. I just need to get through this one on Wednesday, i think this will be the toughest. I still have that Sigma Delta Modulator to design, but i have the opamp, comparator and latch working, now i just need to have a better understanding of what i'm doing.
The spring semester exams are starting next week. I have 4 exams in total since one module was split into 2 big projects and another module was the FYP. Studying for these exams is manageable, the only problem is i'm still working on one of those big projects for the module without an exam. This project is worth 60% of the total grade and it's going to take me a while to finish it. We have until the end of the exams to do it though, but i'd rather get it done by the end of the week so i can focus on studying for the other subjects.
The project task is to design a Sigma-Delta ADC with 3 specifications; 9 bit accuracy, 2.5Khz Nyquist frequency and to use CMOS switches (transmission gates). I'm not sure what he means by putting the CMOS switch thing in as a specification, i mean i dont know what other way i could design it without these switches?! Anyway the circuit design wont be so bad, and i might even get the bonus 10% because i'm doing it in HSPICE instead of PSPICE so i can make a full transistor layout of my op-amp, wheras PSPICE limits the amount of transistors you can use in a circuit. The only problem i forsee is writing a Matlab simulation of the modulator. I HATE MATLAB!
I just can't wait to finish up this year. I sent off my application for Postgrad studies to Southampton yesterday so i'm keeping my fingers crossed that i get that. Also, it was my birthday on Sunday. I am now 22 which sucks. I didn't do much to celebrate other than go for dinner with my family. I got 2 tickets to see the Breeders play in Dublin on the 18th May so i have that to look forward to once these exams are over.
I decided to write a post tonight because i'm on a bit of a high. I just got a big part of my ASICS2 project done. I have to design a 6-bit binary weighted DAC that has to have a minimum of 1V output with an LSB value of 20mV i.e. the maximum output should be (20mV)(2^6) = 1.28V (or 2.28 since the minimum is 1v). Anyway when i say i have a big part of it done, i've been using an ideal VCVS opamp model instead of a designed one and it works with this. Now i just have to make my own opamp and stick this in instead of the VCVS one.
This has been a pretty busy week. On Wednesday i had my FYP presentation and demo, but we didn't get a chance to actually demo our robot because the batteries died! So we're going to demo it to the supervisors tomorrow instead. I think it'll just be a matter of showing up, letting the robot run around and showing how it reacts to various situations like obstacles etc. To be honest i have no idea what the supervisors think of our work, it's really hard to gauge. We have put so much work into this thing that it'll be really depressing if we dont get an A or a high B at least.
Speaking of depressing, i got the result for my opamp design for Analouge Design back. I only got 28.5 out of 40?! The opamp worked and i simulated all the conditions so i have no idea why this result is so bad! I'm looking at the sheet he gave me back now and i don't understand his marking sheme. He doesn'g give numeric marks, he just writes "good" or "average" etc. In the comments he wrote "why is power dissipation given in dB?"...why am i getting docked marks for this? I could have given it in mA but didn't realise that it had to be so specific. In fairness, i did omit a few calcluations (like PSRR, compensation cap etc), but surely that's not worth 12.5%!!!! I'm really upset about this. I wanted to get an A1 or A2 in this module and i hope this doesn't ruin my chance. I might talk to the lecturer tomorrow about it.
Wow i started out this post feeling really positive, now i just want to cry.
Last Sunday, i installed Fahrenheit (usa title: Indigo Propehcy) on my computer. This game was made back in like 2005 but i only heard about it recently. Anyway i started playing on the sunday and had it passed by monday so it's pretty short but every decision you make in the game affects the outcome at the end, so technically there's loads of ways to play this game and i could probably go back and do it all over differently. I'm not sure if i like the story line or not. It starts out as being really interesting but then seems to become a bit far fetched towards the end. It's still a good game and is pretty action packed. Definitely a lot more action than i'm used to from an adventure game.
Oddly enough Fahrenheit ran very badly on my PC. I'm beginning to think that my graphics card is broken. This summer when/if i get a job, i'll have to invest in some new computer parts. With Mass Effect 2 coming out in a few months, it's inevitable. While on the topic of games, Still Life 2 is coming out in America very soon. Originally i was expecting the American and European release dates to be the same but a few days ago i check the website, and the European release date was updated to be pushed back a few months?! No wonder people resort to illegal downloads! FOr the time being, i'm looking for a new game and am open to suggestions. I guess i could always return to Tomb Raider but that damn snake monster is impossible to kill!
We had this week off college...well it was easter week but i was still in the lab working on my FYP every day. I think i have the base recharging station circuit working but the lab was closed today and will be closed on easter monday so i'll have to wait till tuesday to test this. In fact tuesday is my last day to finish all the work for my FYP because my demo day is on monday. I dont think that i will be 100% finished but if i can get the recharging station done, i'll be happier about it. After the demo day, i will post all the working circuit schematics here just in case they're of use to anyone.
So i finished my FYP report tonight. It's 45 pages long which i think is the perfect length. I still have to append an A3 page into the back, so technically it's more like 47 pages. Some of the content is questionable since i haven't fully finished my project yet. For instance, i wrote new AVR code for my microcontrollers today and i have no idea it'll work or not, but i included it in the report anyway. I'll hope for the best.
This week was RAG week in UL. I have been in college late every evening but not engaging in rag week related activities. No, i've just been working. I'll be surprised if i come away this semester without putting on like 10 stone. All i seem to do is sit at a computer, simulate circuits/write code and occassionaly take a trip to the vending machine. They should have a fruit vending machine...ah who am i kidding...i wouldn't use that!
Lately i've been thinking alot about what i'm going to do this summer. I got my ticket to Rock Werchter and i know at least 2 people going to it, but i'm talking about a job. No one seems interested in taking on 4th years as interns and apparently with the current economic climate i'd be lucky to get a job anywhere. Unfortunately i'm a bit of a job snob and refuse to take steps backwards in life so now i need to find a job equal or better than an internship in Irish Rail.
My FYP report is due on Friday. The demonstrations are then 1.5 weeks later. I doubt that my project will be 100% complete by friday so i'll be taking a gamble with the report and writing down that i finished everything. Then i'll have those 1.5 weeks so make that true.
I am pretty close to completion. I'm working on my IR barrier circuit and Charging station at the same time in UL. My IR circuit wasn't working for me until last week. This took me ages to try and fix and in the end it was pointed out by my supervisors that the duty cycle of my IR beam was too high. I would have never guessed this. The problem i was having is that the IR photodiode picked up the IR signal when the reciever and transmitter were in close proximity but when they were moved apart, after like 20cm, the signal was lost. My photodiode is a TSOP1136 so it detects a 36khz IR signal. At the transmitter i'm using a 555 timer to create this 36khz clock.
The duty cycle of a 555 timer is given by:
D = RB/(RA+2RB)
Where RA and RB are shown in this diagram:
Originally in my design i had RA = 22k-32k (variable resistor in series with 22k) and RB = 470ohm, clearly RA > RB, but for an even duty cycle this should be the other way around. So i changed my design to RA = 3K and RB = 15K
This gives me a duty cycle of roughly 50% which boosts the power to my IR led and now the photodiode is detecting it perfectly!
Now i'm going to pass the output of my photodiode into an ATTiny861. I have the AVR code written for this controller but i want to make it a bit more intelligent. Like, if the lower beam is only broken, but it stays broken for more than 2 seconds, then someone is probably crawling through so alert the robot. I dont know though, it's hard to think of things. I'm open to suggestions.
So i'm writing this post in relation to the design of a 2 stage CMOS opamp. This is a project that was given to us 2 weeks ago and is worth 40% of a module. Everyone in the class got different specifications for their opamp. A 2 stage opamp consists of a differential stage and an output stage.
Okay so firstly i have a common mode input range of 0-3.5V. This means that since the range includes 0v i.e. ground, my differential stage will use a PMOS differential pair. This is the first important step because this gives me the differential amplifier circuit layout:
I've been given a specific open loop gain which is 65dB. This is the open loop gain of the whole opamp and since it's open loop this means that we'll have no feeback from the output of the opamp back to the input. The gain is given in dB but can be converted to V/V using 20log(gain) = 65 so gain = 10^(60/25) gain = 1778 rougly. This is the gain of the two stages so
Ao = Av1*Av2 where Av1 is the gain of the differential stage and Av2 is the gain of the output stage. It doesnt matter how we assign these. Like i could make the first stage have all the gain and have the 2nd stage have little gain, but that would be stupid. So instead i'll make the gain 50:50 so Av1 = Av2.
Okay so we need to calculate Av1 and Av2. First we need to assign some lengths and widths to the transistors in the circuit. As you can see, i'm using an ideal current source for the input current. This current flows through the pmos current mirror. The transistor sizes for both of these pmos devices must be identical because we want IDS of Mp1 = IDS of Mp2. Say i set the input current to 2.5uA, then IDS of both Mp1 and Mp2 is now 2.5uA. The formula for IDS is:
IDS = K/2(W/L)(VGS-VTN)^2 Assuming the device is in saturation
We know IDS, set L to be constant e.g 1um, we know VTN and K so all we need to know is VGS to find W. Vgs depends on our common mode input voltage. This can be found by simulation and in my case it's 1.1V. Now we have the current mirror stage completed.
Mp4 and Mp3 can be found in a similar way but this time IDS of these devices is half of the above Mp1 and Mp2 because the current splits in 2 when leaving Mp2. The current through Mp4 and Mp3 is the same for the two Nmos devices. So these are all relitvely easy to calculate. The only issue is changing the threshold voltage in the Pmos differential pair. Since the Bulk is not connected to VDD, there will be a different threshold voltage. I'm not going to put the formula here though cause it invloves phi, gamma and square roots.
So the formula for gain of the differential stage is Av1 = -gmP3(RdsP3//RdsN5).
This is the first step complete. I'll leave it at that for tonight because it's late and i have to get up to teach tomorrow. I'll try do the output stage sometime soon, just in case some future student happens to get stuck on a similar design. The internet can really suck as an educational resource.
So tonight i've been messing around with my new boss RC-2 loop pedal. Okay, it's not new, i've had it since like christmas 2007, but have only started to use it tonight because i was too lazy to figure out how to use it. I eventually figured out how to set a tempo and record a track to be looped. I've been playing with it for the past half hour and it's amazing! Like i can't believe i played before without it. I was able to put in some song that i just thought of and play a small riff over it:
Okay so it's not great but it's a good start, also the video was taken on my phone so obviously the quality sucks. Basically everyone who's serious about the guitar should get one of these. They're like the best value for money loop pedal on the market.
Anyway enough advertising for Boss!
Today i got some great news. One of the junior cert student i teach maths to has gone from getting like a D in the christmas exams to getting 80% in his mocks. This is amazing and very reassuring.
Tomorrow i have a good bit of work to do. I have to start a design for an 2 stage opamp, write 10 pages of FYP report and look into AVR code for my microcontroller. I had a midterm on Friday that was worth 30% of the VLSI module and i think i did pretty well in it. Unfortunately no drums for me this weekend because my Dad is in Morocco and he has the fob for the Gates to the business park where i practise. I was also going to go to Clonmel, but decided not to due to money, weather etc.
Okay so it's only been what, like 2 weeks since i last posted? I thought that since Terran has updated that i should too! Oh listen to this:
I'm really getting into Crystal Castles. They're playing at Oxegen i think. The Yeah Yeah Yeahs are definitely playing so i'm really tempted to go, but i've been talking to a few people about the possibility of going to rock werchter which is on in Belgium. Placebo are playing there and i would love to see them play live. Here's a video of them playing at reading festival:
I'm trying to get my CV together to send to a professor in Southampton in the hope of joining his research group on Mems and Nems (micro/nano electro-mechanical systems). I'm just getting my mother to look over it before i send it to him. It would be for an MPhil/PhD position.
The projects are beginning to pile up in college at the moment. I was just given one today for Analogue IC Design, where we have to design and simulate a 2 stage OPAMP based on a list of parameters e.g. 3mW power dissapation. We have to do this in Spice for 40% of the module and for a bonus 10% we can give him a layout in Magic. I also have to design a Galois Field Multiplier for VLSI based on a given primitive polynomial, but i have this done. Both are due for week 8.
I finished my keypad circuit this week, i just need to put it in a plastic box. Now i'm moving onto my IR door circuit. It have the transmitter circuit done, but i'm not sure how the photodiode is supposed to react when the IR beam is broken so i'll have to figure this out soon. I only have 3 weeks to complete this and still have to program the 2 micro-controllers...basically i'm screwed.
I've gone to write a blog a few times over the past week and after a few lines thought "screw this" and closed the lid of my laptop. This is only for dramatic effect though and i'd reopen my laptop 2 minutes later to continue my mindless internet surfing. It's all these hours i'm wasting on the internet that makes it difficult to write a post...because i'm not doing anything interesting. Starting tomorrow i'm going to really cut down on the time i spend on this thing. I mean i could be using this time way more effectively, like...learning a language or something.
Today has been a particularly uneventful day. I was teaching for 2 hours and thats about it.I am currently watching the Irish Film and Television awards (IFTAS) on TV. Unlike the BAFTAs or the OSCARS there are no A-list celebrities at this, apart from Neil Jordan (is he an A-list?). Also the president was available to handout the lifetime achievement award (i can't imagine this happening in any other country!). Ryan Tubridy is presenting the show and keeps making really bad jokes, like no-one laughs and then a tumbleweed blows by....God i wish i was there!
Tomorrow i'm going to play drums in my dad's warehouse, which i normally do on a Sunday but i'm especially looking forward to it this week! On Wednesday i'll be going to a postgraduate fair on in the RDS, Dublin. But since my student travelcard expired, i cant get a student fare on the train so i'll have to take the 3-4 hour bus journey to get there. So much for working for Irish Rail! Hopefully i'll get a chance to meet up with a few friends in Dublin while i'm up there.
FYP update: I think i may have finally finished my keypad decoder for my robot. It meant having to add an additonal EEPROM and counter for the "off" sequence. I'll post a schematic here once i get the thing fully finished and drawn up. I need to start working on my 50 page FYP report soon!
This post is boring but i'm keeping it up as a testament to how the internet sucks the life out of people.
My family and i would refer to the weather we're having outside by saying "it's stone cold steve austin". This is a wrestler. How we know that is a mystery. I hate how cold it is. It's causing my lips to get chapped and my skin to dry out. It does give me an excuse not to go for a run though....i guess i'm only fooling myself with that one.
Lately i've been giving alot of thought to my past. Mainly friends i used to have. When i was 8 my family moved from Tipperary Town to Clonmel. This isn't a huge leap on the map but for an 8 year old it was a big deal. When you're in primary school, it's like you're friends with the whole class and then you generally end up going to the same secondary school so you know the same people for almost your whole life. When we moved to Clonmel,i tried to keep in contact with the people from tipp but this was before texting, facebook etc so the only method of communication was letters or phone calls.
I have kept in contact with NO people from either of these primary schools. No one in my class in Clonmel ended up going to Rockwell so we all just naturally drifted apart. Rockwell was great and i still keep in contact with all my friends from there. At the end of 3rd year though i willingly moved to Yeats College in Waterford to achieve "academic excellence". I had a good group of friends but once again, once 6th year was over we all moved on.
This means that out of 4 schools i have gone to in my life, i have only kept in contact with people from 1. Sometimes i wonder what happened to people i used to know. Like sometimes it really nags at me to find out. Unfortunately the people i desperately want to know about seem to have no record online that i can google.
Well, i've been really veering off the topic of this blog which is electronics. So i'm going to throw in some info here at the end *TURN AWAY NOW*
I'm still working on my Keypad decoder because i'm also trying to figure out the IR beam circuit at the same time. I should probably focus on them one at a time. I have the schematic ready for the IR transmitter and reciever. Those aren't a problem. The problem is the wireless transmission. Let me explain: When someone trips the beams, this will set a Flip Flop which will be an input to some processing unit. The processing unit will transmit data (probably just a 1) over some device and it will be picked up by the robot. The robot will send back an acknowledge signal which will reset the Flip Flop.
This doesn't sound too bad. An 8051 could do the processing and a simple radio transciever could send and recieve signals right?...Apparently not! It is impossible to find a simple RF transciever. I was originally looking at quad flat pack chips, but then i'd need to get an evaluation kit etc so it's like an FYP on its own. Then we saw some bluetooth modules which could work if they weren't so expensive. Finally i was looking into wireless RS-232 modules which essentially work over bluetooth anyway so these were even more expensive. On the off chance that someone is reading this and can help, please do!
I'm gonna go. I need to get up early. EEPROMS wont program themselves.....lame
Last night, it was my friend Emma's 30th birthday party. To celebrate, a few of us went into town for drinks in a pub and then a nightclub. Prior to this we were out at Emma and Erin's house in Murroe. Here we drank a bit and played "Lips" on the Xbox 360. This is a karaoke game similar i guess to Singstar. It was really popular last night anyway with people wrestling each other for the microphones.
I got home last night at about 4am and had to get up for 12pm to get ready for teaching. That doesn't sound bad but i had a good bit to drink so my sleep was very uncomfortable. Today, my neck and legs are KILLING ME!
I'm just after finishing watching Tomb Raider:Cradle of Life on TV. To be fair, i remember it being way more ridiculous than it actually is. Certain scenes, like when she's driving a motorcycle along the great wall of china, just make me want to die though. It's a pity because i think that they could have made these films great with just some better direction. I was wondering why Angelina Jolie agreed to act in this film since it does nothing for her reputation. Speaking of Tomb Raider, i have only completed 55% since last time. This is because i'm stuck on a tough bit involving a snake monster and i'm lacking the motivation to return to try and beat it.
Well, my hours of mindless television watching paid off today when i stumbled across this ad for cadburys:
Today was the first day back for the spring semester of college. I only had one class at 4pm so i managed to fit in a morning run beforehand. Starting next week, however, i'll have a lab at 9am to 11am and then will have to hang around college until the class at 4pm. It's not so bad though, in fact i'm wondering if they schedule the classes like this so that we can get work done on our FYPs.
The class was ASICs 2 (Application Specific Integrated Circuits). This is an elective i chose out of a really crap list! They used to have Active Circuit Design 5 (ACD 5) as an elective but then they removed this module completely from the course which isn't too great for me since it's my favourite subject. I had to choose 2 electives and so i went with ASICS 2 and VLSI Digital Systems Processing.
When i got back from college, my friend Rob rang me. He's also an electronic engineering student but a year behind me. He said that he was having some trouble with a design question for Active Circuit Design 3. Unfortunately for Rob, they changed the content of the ACD 1 and 2 modules (2nd year modules) to when i did them but they left ACD 3 untouched. When our year did ACD 1, it was based on the basics of transistor theory. We went through MOSFETS, JFETS, BJTS and the first chapter or two covered diodes. When Rob's year did ACD 1, the main focus was diodes. I remember looking at Robs course notes and thinking "this is crazy, you guys are barely touching on any transistor information". I have no idea what ACD 2 consisted of for Robs year but it will be interesting to find out.
Anyway, skipping forward to today, ACD 3 is all based on oscillators, Phase Locked Loops, ADCs, DACs etc. In the oscillators section they cover phase shift oscillators, wien bridge, colpitts, hartley and so on. You kind of need to know how opamps work and so need to know how transistors work. So the lecture gave Robs class the task of designing a common emitter amplifier. The only information he gave is that it has a gain of 60. I'm meeting Rob tomorrow to go through this with him but i will also post the solution here.
Let VB = 1.7v
VE = VB-VBE = 1V
IE roughly equals IC and IE = VE/RE
We want a gain (AV) of 60.
AV = RC/RE so 60 = RC/RE
Let RE = 100 so RC = 6000
Therefore IE = 1/100 = 1mA IC = IE = 1mA
VC = VCC - (RC)(IC)
Let VCC = 12V
So VC = 6V
VB = (VCC)(R2/R1+R2)
1.7 = 12(R2/R1+R2)
R1 roughly equals (6)R2
so if we let R1 = 6K then R2 = 1K
NOTE - I'm not sure if 6k resistors are comercially available so change the values accordingly. Or put resistors in series
Today is the day the christmas exam results are released on the student records website. I woke up at 10.30 and the first thing i did was check mine. I put my hand in front of my laptop screen so i could lower it slowly and break the results gently to myself. I got an A1 in Active Circuit Design, A2s in ASICS and Industrial Automation and 2 B's in both Signals and Systems and Telecommunications. All in all, i'm pretty happy with these results! I kind of wish i had done better in Signals and Systems but i'm really shocked that i did so well in ACD.
Tonight, i am going to see David O'Doherty perform in Dolans warehouse. He's an amazing comedian! I saw him over the summer at the Heineken comedy festival when i was living in Dublin. Jarleth Regan was the MC for the gig and Josie Long was kind of a supporting act. It was a really cool event and i'll definitely go back and see a few acts next year. The gig tonight starts at 8pm which isn't a great time for me since i'm meant to be teaching maths from 6.30 to 8 in Castletroy. I rang Tyree (woman who runs the learning centre) and either she'll push it back half an hour or someone else will take the group. I hope the latter will happen.
My computer is back running again thanks to help from my father. He owns a computer maintenance business (Solve IT) which comes in handy. So i was able to install Tomb Raider on Tuesday and so far i'm 43% complete. It's pretty good apart from slow glitchy parts which might be my computers fault rather than the games. I've already lost my grasp on the story line but i enjoy jumping around, climbing up cliffs, solving puzzles, the usual tomb raider stuff.
I decided to write a post because i'll probably be going off the radar for a while. The reason for this is because i just bought Tomb Raider Legend last night, despite my ridiculous game addiction. It's not the latest Tomb Raider game, but it's been years since i played one so i wanted to start with an older one before i move onto the latest one. The last time i played these games, i was like 13 and cheating my way through the whole game. Its not that the games are particularly hard, but i get really scared by the monsters, tigers etc that attack you so things like "god mode" and unlimited ammo gave me the confidence boost i needed to play.
I should probably do a special games feature for this blog, but it's only recently that i've been getting back into them. Other than Mass Effect, i have passed Sam and Max season 1 and Still Life this year...as in 09. I played Sam and Max because i'm a diehard vintage Lucas Arts fan...you know, back when they brought out non-star wars related games like Monkey Island (my favourite game series of all time!), Day of the Tentacle, Full Throttle e.t.c. That's not to say that i don't like star wars games, in fact i think KOTOR 1 and 2 are among the best games of all time but i'm still waiting for Monkey Island 5! Anyway, Sam and Max is now being released by Telltale games and even though it follows the whole "point and click" structure, i didn't find the dialogue as funny or the stories as interesting to play as the original Lucas Arts Sam and Max game. It was all a bit repetitive. Still Life, however, is possibly the best crime solving game i have ever played. Unlike the CSI series, it's more focused on the story than actual forensic analysis and it's far more interesting to play than the Sherlock Holmes or Law and Order games.
My laptop just overheated and shut itself off there, i'm not sure whether i should thank Firefox for restoring my session or blogger for saving my post! I tried turning on my computer which seems to be broken. I think the harddrive is damaged from the power outage yesterday, i just hope i can retrive important information like my Mass Effect save file. Looks like i wont be starting my new game today. This is probably for the best because i'm really running behind schedule on my FYP. I completed my wire wrapping of the first half of the keypad board, but then i ran out of green wire. I have red, white and black but i'm trying to colour code for neatness and so that it'll be easier to track connections. I'll have to spend the entire day in UL tomorrow trying to finish this off. Previously, i had given myself a deadline of last friday, but i woke up really late in the day and had to teach at 6.30 (which was cancelled). So i have had no access to parts all weekend and no work was done. On the plus side, i did see Clone Wars which was better than i expected even though it didn't feature General Grievous.
God this blog must make me seem like the biggest nerd ever!
About a week ago i bought Mass Effect for my computer. Since it was developed by Bioware i was expecting a similar gameplay experience to Knights of the Old Republic. I was pleased to find out that i was correct! If you haven't played either of the games i have mentionned,go buy them, seriously! Unfortunately i have a small problem with video games. I become so ridiculously addicted to them that they completely dictate my life! I installed the game on sunday and passed it yesterday. That's 4 days of gameplay to pass a game that advertises 80 hours of gameplay. Now that i'm finished, i'm miserable. Still, on the bright side Mass Effect 2 is due for release hopefully some time this year.
I haven't made a huge amount of progress with my robot since my life was this game. I did make it into the labs in college on both Monday and Tuesday though. Okay the difference between this keypad circuit i'm building now and the one i built last year is that i'm now using a keypad decoder chip to replace an EEPROM and D-latch. This did mean that i was slightly confused about how i'd have to alter my original circuit. I thought that by feeding the keypad contacts directly into the chip, i would generate an output like 0000001 for 1, 0000010 for 2 and so on. But i still need to have a circuilating zero on the y inputs using a shift register, clock the decoder everytime a button is pressed, debounce the switches, and now i have to pass all the inputs through an inverter before they are input to the decoder. I probably should have just stuck to the EEPROM and latch configuration, but then i'd have to program the EEPROM and i didn't want the hassle of doing that. Although i'll have to program one anyway.
On tuesday i went to the dentist, for the first time in a LONG time. I had a hole in one of my fillings which she drilled out and refilled. I have to go back to her next week for another filling. It costs 100euro per filling which seems excessive. The filling she refilled is really bugging me! It's like i have a lump on my tooth that makes it uncomfortable to close my mouth. It's become really sensitive too!
Happy new year! Only, it feels just like anyother time and nothing's really changed but i guess people need a new year to make a fresh start. I dont really have new years resolutions, because i generally make my them up as i go along. For instance, back in October i decided to give up sweets and chocolate. I was sucessful in this venture until christmas day which was followed by about 5 days of bad eating. Now i'm back on the wagon and it'll be interesting to see how far i get. Also, around exam time i gave up on exercise and locked myself away for a month. Lately i have started back running and it's been tough. Any fitness i once had is gone and i'm starting from scratch again.
My two main plans for the year are to finish my Degree with at least a 2.1 and to get a Postgrad course in Southampton or Denmark. Both colleges offer a course in Mechatronics. The Southampton one is only 1 year long but will cost 3500 in tuition fees and the one in Denmark is 2 years long but is free. I'm waiting to get my christmas results before i apply for either of these courses.
This month will be dedicated to my Final Year Project. I'm had a nightmare last night about this so i need to really work hard on it. At the moment i'm building the keypad decoder circuit. This is similar to a project i had to do in 3rd year but this time around i'm using a decoder chip instead of making one from a bunch of gates. This might sound easier but now i'm confused as to wether i should be debouncing the switches, pulling up the inputs etc or is the chip already doing that? I'm pretty sure it's as straight forward as feeding the keypad inputs into the chip and then passing the outputs on to the counter and BCD-7 segment display chip but i could be wrong. Another thing i noticed was weird is that the schematic i had drawn in 3rd year uses a 3 input NAND gate to clock the latch. So the X1, X2 and X3 inputs of the keypad are passed into the NAND gate and when one of these inputs goes high, the output is high. But this is wrong because when all the inputs are low then the output should still go high. That means i must have been using an XOR gate instead but then why did i put down a NAND gate in the schematic?!
Once i figure out this Keypad circuit, it'll be on to my Infra Red door beam circuit which is a huge part of the project. I think this will take the longest to complete. Now i'm freaking out again over the time left. I'm going to email my project partner for reassurance.
