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I apologize beforehand for the elaborate description that follows:

The accompying figure shows an Altera CPLD TQFP chip mounted in a socket-adapter for pin access. The chip is brand new (i.e. never been programmed before).

I use an STM32 Nucleo dev kit to supply the 3.3V pins connected to the two IO-banks for supplying VCCIO1 and VCCIO2 on the CPLD (there are 6 VCCIOx pins, but I've only connected 4).

I've connected two GND pins along each edge of the CPLD to a GND pin on the Nucleo (there are more GND pins, but I've only connected two along each edge).

The 1.8V for supplying the CPLD internally is taken by voltage-dividing the 3.3V from the Nucleo. The resistor values should limit the current through the voltage divider to be less than 1mA. Note that all VCCINT pins are connected to the 1.8V.

The JTAG pins of the CPLD are connected to the 10-pin female connector of a USB Blaster that in turn is connected to the programming PC.

When I press the "Autodetect" feature to scan for the CPLD in Quartus programmer, I get "unable to scan device chain". Can anyone immediately see a problem with the setup ?

Wiring setup

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