More parts ordered
OK, so I was missing diodes, so I’m ordering these from sparkfun, based on info over at Julien Bayle’s site.
I’m also now thinking that based on my LED’s “Current – Test: 20mA” and “Voltage Rating 3.2V”.
So the way I’m reading it. I should be getting a 24.5k? – 28k? resistor.
I’ll probably pick a handful up from the local Radio shack – I’m assuming that resistors are fairly common and it’ll be easier to get them there rather than ordering online.
I saw your post on http://bricktable.wordpress.com/30/hardware/
So did you get the same LEDs as me?
digikey# 511-1611-ND
http://parts.digikey.com/1/parts/1381671-led-3mm-468nm-blue-transparent-slr343bc7t3f.html
If so– how did you calculate what resistor you need?
I thought we were supposed to go off the chart on the arduino page: http://www.arduino.cc/playground/Main/MAX72XXHardware#SelectRSet
It says:
20mA 3.0V –> 24.5kOhm
20mA 3.5V –> 22.6kOhm
So we’d need ~23.5kOhm. Right?
Also– did you buy the serial ATA looking cables to attach the shield to the arduino? If so where’d you get em?
They don’t list em in the hardware list– but you can see em plain as day in this pic:
http://bricktable.wordpress.com/30/pictures/dsc_0091/
Correction– PATA looking cables. I don’t know what they’re called…
Hey utoks, yeah I got the same LED’s as you, I’m going to get the 1 resistor you seem to need from radioshack. I looked online but the choice us too great, so I plan to go to a local shack with what I need and hope someone can help me.
I was going to aim for a 27k based on input from this thread…
http://post.monome.org/comments.php?DiscussionID=2285&page=1#Item_17
The diodes shipped out yesterday so I should have them in a day or so.
Cables, soldering kit, some breadboards, spare wires of various sizes, crocodile clips and anything else that looks neat I will also be picking up from my local radio shack probably this afternoon. I’m off work for the next 5 days so I’m hoping to make some progress with my first setup.
Ah straight from xndr– cool. So 27k it is. Yeah I have big midterms next week so I’m gonna start after that. I have all the parts though– as far as I can tell…
I’m gonna take some old floppy cables and ata66 cables and chop em up for my connectors. Hopefully that will work.
What’s your plan for the enclosure?