I/O status of Ultra 37K CPLD during programming

Question: What is the status of all I/Os  of Ultra 37K CPLD during programming?



 All I/Os (except TDO) are tristated during device programming. This allows soldering the devices directly onto user board without having to erase them first. It allows the user to power-up a board and program the CPLD devices on it without worrying whether their initial, non-blank state will cause any problems such as output contention with other devices on the board.      


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