Forum Discussion

Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
12 years ago

Passive Serial Tri-state

I am designing a Cyclone IV based board with an SPI interface that we would like to use to configure the FPGA with an MCU. We will configure the pins to toggle like Figure 8-16 (Device Handbook Vol ...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
12 years ago

Driving a pin high or low will mean it is being driven with a static value - i.e. non-changing.

nSTATUS and CONF_DONE shouldn't be driven, just separately pulled high externally using resistors. These pins reflect the configuration status of the FPGA.