I want to lear VHDL, is Papilio for me?

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I want to learn VHDL, and I am searching for a cheap and flexible board to be my learning partner. Currently I have only done pretty simple VHDL stuff using CPLDs and Xilinx ISE tools, and I want to make the jump to more complex stuff.


Papilio boards look nice, but as they look targeted to "non HDL friendly people", I'm wondering if I will have problems using Xilinx tools instead of Papilio tools.


I was thinking about buying a Papilio Pro board, with an Arcade Mega Wing. I suppose it will fit the Papilio Pro without problems, but I'm not 100% sure, maybe it's only for Papilio One?


Thanks for help!

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The Papilio boards are essentially breakout boards for the Xilinx FPGA they contain along with an onboard FTDI chip for loading the bitstream. Aside from the loader software you use the standard Xilinx ISE toolset with the Papilio and it works much like any other FPGA development board.


Both the Papilio One and the Papilio Pro have exactly the same headers and all the same wings and megawings will work. If you want to use one to learn VHDL I would recommend the Logicstart megawing, you can use that with the arcade games too. If you want a more specialized game platform then the arcade megawing is a good choice but it lacks the LEDs, switches and 7-segment displays of the Logicstart wing.

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>> I want to learn VHDL, and I am searching for a cheap and flexible board to be my learning partner


it may well the best investment you'll ever make into your career, in terms of bang-for-the-buck. This is completely up to you, how much time are you willing to invest.

The sky is the limit (with upgrade paths if just "sky" ain't enough, e.g. Pipistrello, but worry about that when / if you run out of floor space)


The boards are as HDL-friendly as any other FPGA, if that's what you want. For example, use xc3sprog instead of papilio loader - possibly with a standard JTAG cable or the on-board FTDI chip - and it'll provide the usual smallest common denominator you'd expect from a Xilinx FPGA - the chip, flash, JTAG via FTDI chip. Plus a friendly community :)


A personal opinion: The cheapest board will usually do the job for learning, when I'm exploring one feature at a time (this also keeps compile time down).

Nonetheless, it kind of limits my perspective if "my" FPGA is Mr. Dwarf with x kB of block RAM, x < n, with n being what I would need to do something cool.

So the message is, if you can afford to spend some money, don't be afraid to do so. If not, don't let that put you off.


The advantage of a cheap FPGA board is, you're less worried about damaging the board and can focus on more important issues. For me, Papilio is usually the first choice for quick-and-dirty hacks because I'm not afraid to break it . And surprisingly, so far I haven't seen that happen - I wish I could say the same about more expensive boards.

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The Pro is nice in that it has a larger FPGA with a lot more internal RAM. It has external RAM too but this is SDRAM which is a pain to use and not very useful for a lot of the more interesting (IMHO) FPGA projects out there like recreating vintage computer systems and video games, for those you want SRAM. The Papilio One is probably adequate for leaning and you can always get something larger down the road if you decide it's something you want to continue to pursue.


On the other hand, if you want to use accessories like the Retrocade Synth then you need the Pro to make full use of it.

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this is SDRAM which is a pain to use


Don't scare people, james1095. :) It's not a pain to use, it's actually a blessing. Internal RAM is too short, and provided you use a decent controller (ZPUino is quite decent) you can do amazing things.


Not as easy as predictable SRAM, but not as complex as driving an AXI bus....

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Well it's a heck of a lot harder than using SRAM. Let me know when you've got all the classic arcade games and 8 bit computers working with SDRAM for the main program memory, it's certainly not trivial to do so. I've got a 512k SRAM on a daughterboard I made for my cheap Cyclone II FPGA boards and that's a huge amount of memory for pretty much any 8 bit machine. SDRAM is fine for some stuff, but it's far from optimal for the things I'm primarily interested in using FPGAs for.

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OK, I am decided and have the money ready to throw. Just another question: Can these boards be bought from an European store? Importing these boards from EEUU can add a significant cost because of customs...



You can definitely get the Papilio from one of our european distributors:

  1. Exp Tech in Germany
  2. Watterott in Germany
  3. SK Pang in the UK
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