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Altera_Forum's avatar
Altera_Forum
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15 years ago

How quick to go into High-Z?

I am using an FPGA on a parallel bus shared with about 7-8 other devices, mostly ADCs and DACs. I am interfacing the FPGA with the code below to only send data to the Microcontroller when chip-select...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
15 years ago

OK thanks for the tips. I still havent had the chance yet to scope anything out, but my latest hunch is that things are not initializing properly.

I think the FPGA is coming up way before the DSP and taking control of the parallel bus when it shouldn't be. (If I program the Serial Flash Device and reboot both FPGA and DSP I have issues, however if I clear the FPGA then reboot and then program the FPGA using JTAG while the DSP is already up and running,,,no issues).

What is the best way to delay the FPGA from starting up until the DSP is up and running?