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Altera_Forum
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19 years ago

Cyclone II configuration problem

Dear all, I am using an EP2C50F672 Cyclone II FPGA and I am facing problems booting it from the EP2C16. All connections with MSEL and related config pins of FPGA are as advised in datasheet. ...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
19 years ago

>>Check the quality of the Power Supplies. Make sure that there is enough current, and enough bypassing.

3.3V are sourced directly from PCI-X bus which means that there should be no problem. 1.2V are taken from the output of a linear regulator with current capability of 5A. Large enough.

>>Also make sure that the value of the "weak pullups" is not too weak, as some of the >>signals you are connected to have internal pulldowns and you might not be getting >>above their trip point?

We are using the recommended resistor values from Altera, 10kOhm.

>> Also, can you directly JTAG into the Cyclone FPGA and get it runniing correctly?

We can configure Cyclone directly with no problems. We can program and verify the EPCS but FPGA will not start reading from the EPCS.