USB Blaster VCC

As far as using JTAG as a programming sequence, that's fine, and I recommend the having the JTAG header, but programming the FPGA this way will not stick, unless you also support some other means of programming. (IE Active Serial, Passive Serial, etc).

IE It will loose the programming at every power cycle unless you program a flash device to hold the programming.

For Systems with an external CPU, we tend to use either passive serial or passive parallel programming mode.

For systems with no CPU we tend to use Active Serial mode. In this case, we have the "Active Serial" header and the JTAG header so we can program the Active serial device directly. This can be bypassed through JTAG, but it's more complicated, to do it that way.

As far as a USB Blaster compatible device, we've had good luck from Terasic's programmer.

http://www.terasic.com.tw/cgi-bin/page/archive.pl?language=english&categoryno=74

Regards,

Pete

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And by the way, do you know if ebay's cheap copy of the USB Blaster are functional?

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According to the link:

"The mini USB Blaster is another variation of original official altera USB-Blaster. It is based on Cy7C68013 MCU, which use firmware to emulate the FT232BL protocol and drivers and is compatible with original USB-Blaster."

So this version is based on a similar approach to this:

http://fpga4u.epfl.ch/wiki/fx2

based on some reverse engineering performed by Kolja Waschk (kawk)

http://ixo-jtag.sourceforge.net/

http://sourceforge.net/apps/mediawiki/urjtag/index.php?title=cable_altera_usb-blaster

Ask the UrJTAG list whether they have used this cable.

I suspect that it will work fine.

Cheers,

Dave

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I decided to programm my FPGA with JTAG (is it a good choice? Will I be able to programm my FPGA like this?)

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Yes you can program your FPGA with JTAG. Whether it is a good choice depends on what else is on your board. For example, will your board need to configure itself without having to use JTAG?

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But I don't know how to connect VCC: is it the VCC of the IO (in my case: 3.3V), or the VCCint? (So, 1.2V for the cyclone 3...)

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The VCC on the JTAG header determines the voltage of the JTAG signals. The FPGA determines the requirements for these signals. You need to read the handbook associated with your FPGA to determine which bank determines the JTAG signal voltage requirements, and then use the same voltage as the VCCIO for that bank. For example, if your I/Os are all using 3.3V, then the JTAG VCC will be 3.3V.

Cheers,

Dave

And by the way, do you know if ebay's cheap copy of the USB Blaster are functional? Did you try one of those?

(eg: http://www.ebay.com/itm/mini-altera-fpga-cpld-usb-blaster-programmer-jtag-new-/390370232721?pt=lh_defaultdomain_0&hash=item5ae3e10991)