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Altera_Forum
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16 years ago

Advice needed on Cyclone III configuration

I am designing a board with a Cyclone III in EQFP144 package. My I/O voltage is 3.3V and I will be using a serial configuration device. I am wondering about how to wire up the configuration device...
Altera_Forum's avatar
Altera_Forum
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16 years ago

I have the same issue. From Chapter 9 of the Cyclone III Device Handbook, Volume I, page 9-10:

"The MSEL pins are powered by VCCINT. The MSEL[3..0] pins have 9-kohm internal pull-down resistors that are always active."

This leads me to believe that MSEL[3] is stuck at 0 if it is not available in a package. Are you sure that MSEL[3] is pulled high if it is not available in a package?

I'm hoping that this is not the case since I was to use the 3.3V FPP configuration mode (MSEL[3..0] = 1110) on the PQFP-240 package. Is this supported?