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Altera_Forum
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14 years ago

USB blaster download cable -- Data rate on 10-pin connector

On the USB based Blaster download cable to program the Altera FPGA, we would like to know the Data Rate of signals while programming the FPGA. We are in need of this support information i...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
14 years ago

The JTAG clock speed of USB Blaster is 6 MHz (fixed). Another 20 inches isn't a problem of clock speed, but may possibly cause more signal overshoot or even double clocking by distorted TCK edges.

I'm using extended JTAG cables occasionally, but the system boards have mostly series resistors and clamp diodes, I can't guarantee that it works with your boards as well.

As an additional observation, the AS programming interface is more sensitive to signal quality issues than JTAG.