如何在HDL中设定状态机上电初始状态○
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I want to create a group of FFs which power-up in a certain state. How can I do this in HDL without creating an extra port in my design using Alliance1.4?
The ROCBUF was created for synthesis users who needed to create FFs which would power-up in a ‘1’ or ‘0’ state, but the FF would not have an asynchronous reset or set pin. FFs in XC4000 type devices with an asynchronous reset pin will powerup as a ‘0’. FF’s in XC4000 type devices with an asynchronous set pin will power-up as a ‘1.’ By describing FFs with an asynchronous set or reset pin, you can create a group of FFs that power-up in a known pattern, l……