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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
Icon for Honored Contributor rankHonored Contributor
9 years ago

One more thing 


when ST_WR_RAM =>	  
    ram_addr := to_integer(unsigned(addr_bus));
    ram_mem(ram_addr) <= REG_DATA1_IN;
					 
when ST_RD_RAM => 
    ram_addr := to_integer(unsigned(addr_bus));
    REG_DATA_OUT <= ram_mem(ram_addr);
				
when ST_RAM_TO_MCP25625  => 
    temp_ram_val <= ram_mem(ram_addr);

I get - Error (10028): Can't resolve multiple constant drivers.

If I comment out REG_DATA_OUT <= ram_mem(ram_addr); or temp_ram_val <= ram_mem(ram_addr); It compiles without errors.

Why I can't write to different signals in the same process?