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Altera_Forum
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12 years ago

What is Timing between nCEO and DCLK in a multi-device AS Configuration ?

Is there timing requirements between nCEO and DCLK when configuring two FPGA's from one EPCS device? The master device (the first FPGA configured) operates in an AS configuration mode and once ...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
12 years ago

What are your MSEL settings?

The second device should not be in AS mode, but in PS mode.

Ah, but we've had this conversation before ...

http://www.alteraforum.com/forum/showthread.php?t=42710

The nCEO->nCE timing is not critical. The configuration file has a number of dummy bytes between configuration images, and they help account for any delays. I've never seen any issues; I have one design where I've cascaded four Stratix II FPGAs uses FPP mode, and another design where I've cascaded 10 FLEX10K devices uses PS mode.

Cheers,

Dave