Hi
To answer your questions:
- All four capacitors are 0.1uF (100nF) ceramic capacitors rated at 5v or higher. - R1 will depend on the LED you use. If you don't fit the LED then you can omitt R1. As for the value of R1: I orignally spec'd this in the 400 range, but that's probably a bit low and really should just be based on the LED you yourself use (standard ohms law). Example: For a 3mm "intense" blue LED rated at 3.2v I normally only go for 2mA as that's more then enough brightness: 5v - 3.2v = 1.8v 1.8 / 0.002 (2mA) = 900 R1 = 900 ohms
For a standard red 3mm LED rated at 2v I normally use 4mA: 5v - 2v = 3v 3 / 0.004 (4mA) = 750 R1 = 750 ohms
You can always experiment with a resistor with the LED in series on a bread board for what you find ok.
- The component near C28 is JP1: a standard 0.1 inch two pin header which can be used to provide power and ground *.
* The adapter board can be powered in one of two ways: 1) Don't bother plugging the adapater board into a bread board and instead provide power and ground to JP1 (0v pin is closest to C28 and +5v pin is the one furthest away) 2) Plug the adapter board into a bread board and provide +5v to one (or more) of the following pins: 3,15,23,35 and provide 0v / ground to one (or more) of pins: 10,22,30,42. If you choose to do this then you can omitt the JP1 header although for the price of a 2 pin header I'd fit it anyway. Whichever way you power the adapter board you do need to power it as the programmer that you connect to the JTAG header will most probably not provide this and will fail without it. Plus, for breadboard testing, you'll need the power anyway.
If I've over explained things and beaten you over the head with information you already have figured out or know then apologies: Just thought I'd be as thorough as possible. If I've missed anything off or you have further questions then please fire away. You may also have to PM me to get my attention though.
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