microcontroller thread #3

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The data sheet offers a range that lets you use down to 5pF loading on the HS side, and the capacitors are often calibrated at something like 7 pF.
so, here is my cart at allied electronics' website. is there anything else you think I should add? the regs are for making my own supplies out of supplies of different voltages. also, I have 2 MCUs so I am buying crystals for both.

do you think I should buy anything else? or wait till I have a real project?
Think about whether you want to grab a dollar or two worth of stuff to get it under the same shipping charge. It wouldn't hurt to get an extra capacitor or two in case you destroy one by accident.
any suggestions on things that might come in handy? I don't want to get my order and realize I forgot something =]. I am not really in a hurry anymore, as classes start next week, and I will still be working my co-op. I don't plan on doing anything major till winter.
I was trying to find some low dropout voltage regulators on that site but I can't seem to find the ones I was looking for. Mouser has them.

Also, just in case, get a couple of 30 pF capacitors.
I've decided to wait for a while to order any 40 pin PICs. The idea of using the 18F4550 is interesting because the computer can talk to it through the USB port, so it's a favorite right now. Maybe in a few weeks.
hmm, the 4550 looks interesting. do you think my programmer can program it? I wouldn't imagine there would be big changes from chip to chip.
Most likely it can. Look at your list. I think that even if your programmer's software does not list the chip you can find the addresses of the registers and set up equates to names for them and then the programmer will program them like other memory addresses.
One of my favorite ideas for the USB chip is to buy a 18F2550 in the 28 pin SOIC style. It's a lot easier to make a board for it and solder it than with the small form factors of the 40 pin chip.
speaking of communication, I was thinking about what it would take to make a pic wirelessly communicate with, say a computer. could one simply interface the pic with a 802.11 pcmcia card? or would one have to do the signal processing themselves? I have not really looked into it yet, but it seems like the signal processing and packet verification would be done within the card.

anyway, if you have a specific thing in mind, then yeah, I would only get as many pins as you think you will need. the reason I went with a pdip40 was because I figured that 34 I/O pins could cover me no matter what I need to do.
I would look into using a USB ethernet adapter for that. There is prior art out there, you can just assume that and look for it on Google. Obviously the two-wire plus ground and power connection is quite appealing. The 2550/4550 type is cheap and fairly simple.

I don't have a specific thing in mind right now but the idea of a computer controlled shortwave receiver comes to mind.
I would look into using a USB ethernet adapter for that.
you mean like an airport card? (usb wifi). I just think it would be cool to wirelessly gather data, I don't really care if I use lots of pins.
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The absolute easiest way should be with a wireless USB extender, actually.


That one says it transmits and receives up to about 300 feet indoors. Interference could be a problem and I don't know how big a problem. Security is built in. You have to have documentation and code to get the project to talk to the adapter. The adapter needs some kind of setup and has useful features that should be transparent to the user.

Wireless USB products on Newegg
hmm, I was thinking about what it takes to make a joystick out of a microcontroller. I wonder how hard it would be to do a usb joystick. have you run across anything like that in your Internet travels?
I think that these days all the joysticks that you can buy are USB or can do USB. I wouldn't make one without a special need.

It probably wouldn't hurt to get some 1 amp Schottky diodes when you send in your next order. They're pretty cheap. The people who put the projects out on the net seem to think that this improves the ICSP setups somehow. Look for a lower forward voltage drop like about .42, some of them have that.
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