A device for communicating between cores, characterized by comprising: a postbox component, configured to store a message sent from a message sending core to a message receiving core and notify the message receiving core to read the message; and a bus adapter component, connected between the postbox component and the message receiving core and the message sending core which communicate with each other and configured to provide read/write interfaces of the postbox component and the message receiving core and the message sending core; wherein the postbox component comprises: a bus interface element, configured to achieve a mutual exclusion of a read/write message by multiplexing a bus error feedback register, the bus interface element comprises a first mutual exclusion element, configured to achieve a function of a mutual exclusion lock by multiplexing the bus error feedback register, so as to achieve a mutual exclusion of a plurality of message sending cores writing messages to the postbox component; and/or a second mutual exclusion element, configured to achieve a function of a mutual exclusion lock by multiplexing the bus error feedback register, so as to achieve a mutual exclusion of a message sending core writing a message to the postbox component and a message receiving core reading a message from the postbox component; wherein the bus interface element further comprises: a triggering subelement, configured to trigger a state of the bus error feedback register to change after the message sending core writes a message to the postbox component, or the message receiving core reads a message from the postbox component; the postbox component sends a first response message to the message sending core after the message sending core writes a message to the postbox component, wherein the message sending core determines that the message sending core successfully writes the message to the postbox component according to the first response message; and/or the postbox component sends a second response message to the message receiving core after the message receiving core reads a message from the postbox component, wherein the message receiving core determines that the message receiving core successfully reads the message according to the second response message. a postbox component, configured to store a message sent from a message sending core to a message receiving core and notify the message receiving core to read the message; and a bus adapter component, connected between the postbox component and the message receiving core and the message sending core which communicate with each other and configured to provide read/write interfaces of the postbox component and the message receiving core and the message sending core; wherein the postbox component comprises: a bus interface element, configured to achieve a mutual exclusion of a read/write message by multiplexing a bus error feedback register, the bus interface element comprises a first mutual exclusion element, configured to achieve a function of a mutual exclusion lock by multiplexing the bus error feedback register, so as to achieve a mutual exclusion of a plurality of message sending cores writing messages to the postbox component; and/or a second mutual exclusion element, configured to achieve a function of a mutual exclusion lock by multiplexing the bus error feedback register, so as to achieve a mutual exclusion of a message sending core writing a message to the postbox component and a message receiving core reading a message from the postbox component;