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Altera_Forum
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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
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15 years ago

The problem is usually related to TCK signal quality. Some JTAG actions, e.g. configuration download are working, other actions are not working.

In one case, JTAG was working well, after I put a small capacitor (22 pF) in parallel to the TCK pull-down resistor (near the FPGA).