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JTixi's avatar
JTixi
Icon for New Contributor rankNew Contributor
7 years ago

Is it possible to force all I/O HighZ before programming (CPLD Max_V)

On our circuit board, the TDO line as been linked through another I/O pin which is not used in the project (BGA 100 package). The ​first programmation was good. However the unused I/O are linked to g...
YuanLi_S_Intel's avatar
YuanLi_S_Intel
Icon for Regular Contributor rankRegular Contributor
7 years ago
Hi Jean, By right the I/O pin are tri-stated with weak pull-up before configuration, i dont see any problem here. If you would like to program the device again after it is in user mode, you may change the state of the unused pin. To do so, go to Quartus -> Device -> Unused Pin -> Input pin as tri-stated with weak pull up. YL