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Altera_Forum
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9 years ago

Can't resolve multiple constant drivers

I have a process type StateType is (ST_IDLE, ST_WAIT_DONE, ST_START_RX_DATA, ST_RX_DATA0, ST_RX_DATA, ST_RX_REG_COM, ST_RX_REG_ADDR, ST_RX_REG_DATA, ST_TX_REG_COM, ST_TX_REG_ADDR, ST_TX_R...
Altera_Forum's avatar
Altera_Forum
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9 years ago

The state machine needs to exist in a single process.

You communicate with a process via signals.

You can just have outputs from the state machines when something have finished etc, or just read the state of the state machine.

It sounds like you're taking VHDL as a programming language. You may need to draw out your intended circuit BEFORE writing any VHDL. without knowing what circuit you want, you will not write the correct VHDL.