Forum Discussion

Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
18 years ago

Missing virtual jtag documentation

Hello, I started to use the sld_virtual_jtag Megafunction for low level debugging puposes, using Tcl interface with quartus_stp. Now I'm considering possible operation with non-Altera JTAG inte...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
15 years ago

The reported issue of Signal Tap not working with a specific board hardware is very likely a pure hardware problem. There have been previously problems with Virtual JTAG functions, that haven't been correctly operated by Quartus tools under certain conditions (not related to SignalTap), but those are gone since a Version 8 service pack, if I remember right. I hope that no new JTAG bugs have been introduced with Quartus 10, which I'm not using yet.

P.S.: The last VJTAG related Quartus bug, I'm aware of, has been fixed with Quartus V9.0. It involved failure of SFL in certain combinations with other VJTAG instances. The bug had been located in the programmer tool operation, not the VJTAG logic itself.