Serial Configuration Problem of Cyclone III

[Altera_Forum]

Dear experts, 

 I have a batch of PCBs which have two Cyclone III FPGAs. One is configured as AS mode and the other PS. They are designed to be programmed either through JTAG or serial flash.    Some of the boards cannot be programmed via flash, although there is no problem using JTAG with a sof file.   I use Quartus Programmer and tick the boxes "Program/Configure" and "Verify" after selecting my pof file. The message returned says everything is OK.   Does that mean there is nothing faulty with the flash memory and I should concentrate on the connections between FPGA and flash to debug the problem?

[Altera_Forum]

--- Quote Start ---  I use Quartus Programmer and tick the boxes "Program/Configure" and "Verify" after selecting my pof file. The message returned says everything is OK.  --- Quote End ---   If verification was successful than it means that EPCS is OK. There are many reasons why FPGA can't configure itself (errors in configuration scheme, problems with pull-up resistors, problems with connections between FPGA and flash and so on) so please give us more info about your configuration scheme.