I think that the first byte of CFM memory includes special function bits like Program DONE and bits relevant to security features.
Now I'm suffering from an abnormal phenomenon as I try to read out CFM memory contents after programming CFM memory.
For instant writing data 0xFE on the first byte of CFM seems to affect reading out CMF. According to the programming specification of EPM240xx devices, Writing 0xFE on the first byte will not affect reading CFM because
it does not activate the security feature. But writing it result in 0x00 data out put as I read CFM. I'd like to know why 0x00 data out happens although I didn't set security bits.
Please kindly advice to my concern. Thanks.
This question should be same question from this thread, thus please refer to this thread:
How did you get/generate the data to write into the CFM memory block? If you are using your own programmer, then you should be referring to the .pof or .svf file for the correct data that need to be write into the CFM memory block. You should convert the .pof file into a .svf file. The .svf file contain all the correct programming sequence and data that user can use to program the CFM + UFM. You can refer to the how to video on the steps to generate .svf file:
Also you can refer to the attached document for an example of the .svf file.