Chief Delphi - pic: Custom Built Stopwatch

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- - pic: Custom Built Stopwatch (http://www.chiefdelphi.com/forums/showthread.php?t=31816)

Re: pic: Custom Built Stopwatch

Quote:

Originally Posted by abeD

apparently the new one is VHDL only??

It defaults to VHDL, but you can still do schematic design if you want. I've done it with the board I mentioned above. I haven't taken the time to learn VHDL yet and really I prefer the schematic at this point as it feels like I have a little more control over it. Of course, once you start to get really complicated designs then designing a schematic starts to become cumbersome or even impossible.

Check out http://home.freeuk.com/fpgaarcade/games.htm for an interesting application of FPGAs - these guys have recreated various old-school arcade hardware inside an FPGA. Pretty neat.

Re: pic: Custom Built Stopwatch

Quote:

Originally Posted by Dave Flowerday

Cool project! I always liked those types of projects in college, though figuring out why it is broken quickly becomes a challenge with so many wires!

If you (or anyone else reading, for that matter) are interested in experimenting more with digital logic design, you should think about getting an FPGA development board. For those who don't know, an FPGA is a chip that you can download a digital circuit into. You draw a schematic using a program on your computer and then you can download that schematic into the FPGA. It's very cool since you get all the fun of designing a circuit without the hassle of dealing with stripping wires, breadboards, etc. Anyway if anyone is interested in this, check out https://digilent.us/sales/Product.cfm?Prod=pegasus. It's a nice little FPGA development board that has a nice set of IO devices onboard to play with. It's only $89 (I know, I know - that's a lot of $$$ for a high school or college student, but it's worth it if you're thinking about a computer engineering career) and it comes with the programming cable & power supply. All you need to do to get it going is download the software for free from Xilinx.

One question. Are those things re-usable (meaning you can program over and over again) or are they just a one time thing, like a PLA

Re: pic: Custom Built Stopwatch

Quote:

Originally Posted by Kyle Fenton

One question. Are those things re-usable (meaning you can program over and over again) or are they just a one time thing, like a PLA

They're definitely reusable. The FPGA itself is RAM-based, so you can download to it over and over as much as you want. The only problem with RAM is that when you power off your design is gone :(. Luckily, the prototype board that I mentioned (and most others, I believe) include a flash chip which you can download your design into. Then when power is turned on, the FPGA will automatically boot itself from the flash chip. This happens so fast that it appears instant.

One of the applications of FPGAs is to allow designs to be updated or changed in the field (after a product has shipped). (FYI, FPGA stands for Field Programmable Gate Array).

Re: pic: Custom Built Stopwatch

Quote:

Originally Posted by Dave Flowerday

Check out http://home.freeuk.com/fpgaarcade/games.htm for an interesting application of FPGAs - these guys have recreated various old-school arcade hardware inside an FPGA. Pretty neat.

That sounds similar to my final project for my design of digital systems (senior level) course. It was a simple pong like game on an Altera development board. It used a standard monitor (640x480 and 8 colors), and a ps2 keyboard.

For the freshman level digital course, we did a counter/stopwatch on the same board.