No 7c81 board found

Hello, I am an final year Electrical Engineering student of NEDUET Karachi Pakistan. I'm building a 5-axis simultaneous CNC machine as my final year project. When I'm connecting Linux CNC with Mesa 7c81board using raspberry pi 4, there is an error found "No 7c81 board found". Can anyone please help me in this? Well I connected raspberry pi-4 with Mesa 7c81 by IDC40 pin only. Should mesa 7c81 need external power supply for power up? Is this problem occuring due to hardware connection?. 

Are there any red lights illuminated on the 7C81?

Also it's never a good idea to do a flash write command unless
communication with the card is known to work and be reliable
(test with a read command)