error message: "can't verify device number 1"

Hello Dan,

as you already found out, only the CFM part is responsible for the logic configuration. Although the UFM part is programmed by default, it would be only needed if you are using the user flash in your design and want to initialize it during device programming. In some designs, it may be in contrast desirable to exclude UFM from an logic update, e. g. cause it contains calibration data or device personalisation.

I never experienced similar problems with MAX II user flash. I wonder if you have some logic that is unintentionally rewriting the flash and thus exceeds the possible number of reprogram cycles after a short time or if the flash content may be self-modfied between program and verify?

Anyway a read-back of UFM and compare with original content may help to understand the issue.

The JTAG and power-up point in the handbook should be always satisfied when using a TCK pull-down and a TMS pull-up. Actually, MAX II has already built-in weak resistors, but they may be overdriven by an external circuit sometimes, so it's better to use the suggested external resistors.

I understand from your post, that the power supply shouldn't be a problem. To be sure, I would perform the test for VCCINT during device programming, that's described in the handbook.

Regards,

Frank