Data transfer device and data transfer method

A data transfer method in a data transfer device including one or more data transfer control units configured to control a command issuance and a data transfer separately, a command issuing unit configured to determine priorities of commands and issue the commands in an order from a higher priority, a memory communication control unit configured to carry out the data transfer corresponding to the commands thus issued from the command issuing unit from and to a memory, and a signal output unit configured to output a completion signal indicative of a completion of the data transfer with one of the data transfer control units in response to a request for the data transfer from the memory communication control unit in a case where the data transfer is normally completed, the data transfer method comprising:

• receiving, from a data transfer control unit amongst the data transfer control units, a request for resetting said data transfer control unit, the request for resetting coming after the command issuance by the data transfer control unit and prior to data transfer by the data transfer control unit;
• (a) issuing, by the command issuing unit, a pseudo command corresponding to the request for resetting and having a priority to be lower than a priority of each of other commands issued by the remaining data transfer control units which have not issued a request for resetting;
• and
• (b) outputting by the signal output unit, when the request for resetting the data transfer control unit is received, a dummy completion signal to the memory communication control unit;
• and
• (c) discarding by the memory communication control unit, in a case that the request for resetting the data transfer control unit is received when the data transfer control unit has issued a read command, data read from the memory in response to the read command.

A non-transitory computer-readable storage medium storing a program for causing a computer to execute a method of transferring data, the method comprising:

• (a) controlling a command issuance and a data transfer separately;
• (b) determining priorities of commands and issuing the commands in an order from a higher priority;
• (c) carrying out data transfers corresponding to the commands issued in (b), from and to a memory;
• and
• (d) outputting a completion signal indicative of a completion of a data transfer controlled by a data transfer control unit, in a case that the data transfer is normally completed, in response to a request for the data transfer,
• wherein a priority of a pseudo command corresponding to a request for resetting the data transfer control unit, the request for resetting coming after the command issuance and prior to the data transfer, is set to be lower than a priority of each of other commands to be issued in (b), and wherein the method further comprises:
• (e) discarding by the memory communication control unit, in a case that the request for resetting the data transfer control unit is received when the data transfer control unit has issued a read command, data read from a memory in response to the read command.