Intel® Quartus® Prime Software
Intel® Quartus® Prime Design Software, Design Entry, Synthesis, Simulation, Verification, Timing Analysis, System Design (Platform Designer, formerly Qsys)
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cant get one-hot with VHDL in quartus II 8.1

Altera_Forum
Honored Contributor II
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Can anyone help me with implementing a one-hot state machine in quartus II 8.1 with VHDL.  

 

I created a simple test file and set the state machine processing to one-hot in 'More Analysis and Synthesis Settings' 

 

When I go to simulate, the node finder gives me four registers for the four states, but one of the states remains undefined, and the encoding appears to be a combination type like grey or johnson. 

 

Also tried an enumerated encoding which didnt work either. 

 

I attached the code I was trying to use. 

 

Thanks in advance for any help.
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Altera_Forum
Honored Contributor II
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In your example code, the FSM attributes must be deleted, to make Quartus recognize a state machine. But then it's synthesized in one-hot style, also in default auto mode. 

 

I guess, you didn't consider, that the s1 state bit is always inverted, so that an all zero state vector corresponds to initial state s1.
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Altera_Forum
Honored Contributor II
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Thanks FvM 

 

The FSM deletion fixed it.
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