Using on-board USB blaster to program other FPGAs

It's not possible with the default setup for two reasons:

1. The TDO signal coming back from the FPGA on your Cyclone III board will conflict with the TDO signal from the external board

2. If the on-board blaster detects that a cable is plugged in to the jtag socket then it will disable itself

You can probably work around both of these with clever setup on the analogue switches / links on the board, and with care about what you do to pin 2 and 10 (I think) on the cable. If you do get the board set up so there are no conflicts then you may have issues with signal integrity due to large capacitive loading on TCK/TMS/TDI from the original board.

So not impossible, but difficult to do properly, which is why this sort of use is unsupported.

Thanks! I think I will buy a new programmer :-)

Davide

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Thanks! I think I will buy a new programmer :-)

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Buy the Terasic USB-Blaster, its significantly cheaper than Altera's version.

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

If you must have an Altera version, then buy a development kit that includes the programmer. For example, I recently replaced a MAX II PCI kit that I'd managed to damage.

http://www.digikey.com/scripts/dksearch/dksus.dll?vendor=0&keywords=dk-maxii-1270n

The kit is ~$160 and includes an Altera USB-Blaster. A USB-Blaster by itself is $300 ...

http://www.digikey.com/product-detail/en/pl-usb-blaster-rcn/544-1775-nd/1212940

go figure ...

Cheers,

Dave

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Buy the Terasic USB-Blaster, its significantly cheaper than Altera's version.

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Thanks for the advice!

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If you must have an Altera version, then buy a development kit that includes the programmer.

[...]

The kit is ~$160 and includes an Altera USB-Blaster.

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I think that this had been my boss' original thought (in fact, I need it at work)...but probably he did not check if that particular starter kit (DK-START-3C25N) had a separate usb blaster.....

Now I've to decide which one to buy...but I think that if the Terasic blaster is ok for Cyclone III FPGAs, I will buy that one :)

Thanks a lot,

Davide

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if the Terasic blaster is ok for Cyclone III FPGAs, I will buy that one :)

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It works fine.

Cheers,

Dave