Hi group,
I would like to share an impression I have.
Trying to erase and/or reprogram one Altera MAXII EPM1270 device using the Quartus 5.0 Sp1 Web free edition software and the ByteBlasterII programming adapter kept on failing (same thing with ByteBlasterMV and previous revision of the soft).
After considering lots of possibilities (missing pullups, pulldowns, JTAG clock with glitches, although none observed), I finally decided to have the component de-soldered and a new one resoldered.
IT NOW WORKS.
Re-thinking the whole thing from the start, I now wonder if this behaviour is not due to the previous use of the security bit. I remember I set the security bit once on that device (on two different prototypes, both of which were exhibiting the same problem).
The security bit, once set, should I believe not prevent the component from being erased and re-programmed (am I right or wrong ?). If you read the MAXII specification, it seems so.
The symptoms were :
Error: Can't recognize silicon ID for device 1 Error: Operation failed
on both prototypes.
Both prototypes are now working with the new soldered components.
Has anyone experienced such a behaviour before ?
So, I do believe that the problem could be once the security bit is set.
It could also be due to an incorrect definition of the length of two non Altera devices part of this JTAG chain (4 instead of 16), but anyway it is so strange that one could set a condition in the component that prevents it from being re-programmed.
Software bug ?
Any idea ?