Double-CPU information interaction method in relay protection device

The invention discloses a double-CPU information interaction method in a relay protection device, and the method comprises the steps: enabling a protection CPU to only transmit data to a double-port RAM during normal operation, transmitting an operation enabling signal to a man-machine CPU after the writing is completed, and enabling the man-machine CPU to read the double-port RAM after the man-machine CPU receives the operation enabling signal; setting a constant value: after the constant value setting unlocking signal is received by the protection CPU, sending an operation permission and writing permission instruction to the man-machine CPU; after the man-machine CPU sends the to-be-set constant value to the dual-port RAM, enabling the protection CPU to withdraw the operation permissionand write a permission instruction, and read the constant value from the dual-port RAM; enabling the protection CPU to send a constant value setting result to the dual-port RAM constant value confirmation area and then send a