mcroberts has another book called beginning arduino which includes all the LED projects from the kit manual as well as a whole lot more (DC motors, LED displays, temperature sensors, RFID's, etc.). i was hoping the mistakes would be corrected in the bigger book but they're still wrong.
so a few thoughts:
i'm still not sure how a button switch is wired. the pin is wired to a resistor that's wired to the switch that's also wired to the ground? maybe the diagram i'm looking at is showing an atypical configuration. i'll have to look into it. i've studied the schematics, the wiring makes more sense to me now.
* i could use some diffused LED's. the ones that i have are clear, the lights are super bright to the point of blinding. diffused LED's would solve this problem and would look better.
* wiring something simple like this traffic/pedestrian light simulation has already used up half of my breadboard wires. i'm going to need more wires if i plan on doing more complex projects.
* i need to get some batteries in order to run my projects untethered.
* plugging things into the breadboard feels like acupuncture. i'm also worried about snapping the wire leads but it hasn't happened so far.
* i'm sort of cheating with the code: since the kit manual came with code files, i just copy it into the IDE and load it into the arduino board instead of copying it all out from the book.
* an arduino board all lit up with various colors of LED's make for an interesting macro photo subject.
* the hardest part for me is the wiring. once that's all done, there's still the code that has to be written. i'm more familiar with the code side of things, but it's a change of pace to get to work on the hardware.
drew's disappointment over my lack of proper wine glasses made me pay a visit to craig's list, my favorite place to procure cheap items. a search of "wine glasses" pulled up several local sellers. a person in boston was selling an unused boxed set of 6 ikea wine glasses for $5 - an extraordinary bargain until i discovered that's actually the ikea retail price. i finally settled on a seller in east cambridge who was moving out and getting rid of a bunch of household items including 6 glasses for $4.
the seller contacted me this morning, a dutch national from the sound of her name. she asked if we could meet at kendall square around 4:00, i said sure.
but first i needed change. instead of going to the bank or simply buying something from a store, i paid a visit to the cafe where i got change from my father (my mother had already gone home by then).
returning to my place, i made a detour to porter square to pay a visit to michael's. maybe i didn't see it last time, but there is a big store sign. michael's occupies the basement space that was formerly burlington coat factory. i'd never been to that store either, but i imagined it wasn't very big. after taking a short ride on the escalator i was amazed by just how big this subterranean crafts store really was. in terms of spare feet, i'd imagine it's just as big as the supermarket on the surface floor. this was definitely not some small satellite store but one to possibly take the place of another subterranean cambridge crafts store (i'm speaking of dearly departed pearl in central square). since it was a new store (less than a week old!), all the shelves were well stocked and everything was organized.
i had some 40% off coupons in my pocket but there was nothing i wanted. i called my mother to see if she needed yarn but i couldn't reach her ( there was reception, she just didn't answer). i would've bought some halloween colors LED string lights if they had anything, but they were already making a push for christmas decorations and there wasn't much halloween stuff.
about to leave for home, i was inspired to pay a visit to radio shack. i was on a search for electronic parts, which against-all-odds radio shack still carries even though most of their business these days is signing people up to cell phone plans. their entire inventory of electronic parts could easily fit on a space half the space of a home refrigerator. prior to working on the arduino board, i would've been interested in these parts, but i wouldn't have understood what most of them were used for. this time around however, my eyes were opened, like a whole new world opening up. every drawer i opened, i saw things i could potentially use. radio shack also sold authentic arduino boards, although an uno revision 3 (i have revision 2) cost $35, which is almost what i paid for my entire arduino kit including all the sensors, wires, storage case, breadboard, etc. i definitely got my money's worth.
i made it to kendall square close to 4:00. nanette didn't give me her phone number (she might've cancelled it already before the move) but gave me a description of what she'd be wearing and that she'd be on a bike. she actually saw me first, had everything carefully packed in a large shoe box stuffed with kitchen paper towels. i paid her the $4 and tucked the box into my backpack. a bunch of people waiting for the bus watched our mysterious transaction; i ignored them as i pedaled home.
i went to the dollar store to score some cheap batteries for my arduino ($4 for a pack of 8). maybe they were too cheap, because when i connected the loaded battery pack (6 batteries for 9 volts), nothing happened (i'll need to take it to belmont and have my father check it with his volt meter). in an inspiring moment, i realized i had a perfectly nice 9V (850mA) power adapter so i plugged that into the arduino. the lights turned on but they were flashing like crazy. i quickly pulled the plug for fear of damaging the board. later i learned an important lesson about power adapters: not only do they come in different voltage and current ratings, but they can either be DC or AC. the one that i had was a 9VAC, and the arduino requires a 9VDC. that got me thinking so i checked the LED display board and saw that it needs a 9VAC. unfortunately, the plug i ordered on ebay a few days ago is actually a 9VDC, so i don't know if it'll work. worse case scenario, i can give the plug to my arduino.
in the late afternoon i began round 2 of my arduino training. project 5 was to create a simple chase effect using LED's. there wasn't anything new to learn with the wiring, but the code introduced for-loops and using the millis() function as a timer. project 6 was an extension of the chase effect, except this time i'd wire a potentiometer so i dial the speed of the LED animation. it didn't work the first time, but that was because i connected the potentiometer to digital pin 2 instead of analog pin 2. once i made the fix it worked, although the increments jump very quickly from flashing to suddenly all steady.
i had dinner in the early evening, rehydrated some leftover meat buns. i'd put them in the fridge uncovered so they'd turned hard. my father told me to steam them on the stove (not in the microwave) and sure enough, they came back to life, soft as they day they were made. drew came home right around that time, around 5:30.
drew left around 6:00 to attend some sort of architectural reception. he seemed reluctant to go but there was free food. he returned before 8:00, confined to his bedroom since the temperature inside the house tonight was 60°F.