Patent ID: 8601182

Claim:
A data communication control device comprising: a controller comprising a plurality of channels each of which is prepared for one of multiple data transfer destinations and a plurality of command queues, each of which is allocated corresponding to each channel and which stores a command for data transfer through each channel, each of the plurality of command queues having a corresponding threshold, the controller executes a command in order from a head in each command queue; and, an overall controller that stores a command in one of the command queues when the number of commands stored in any one of the command queues is not over a first threshold value, the first threshold value indicating an upper limit of the number of commands stored in the any one of the command queues, and stops storing the command in all the command queues and stores the command in a waiting queue when the number of commands in anyone of the command queues is over the first threshold value, wherein the overall controller pulls the command out in order from a head in the waiting queue and stores the pulled command in a corresponding one of the command queues which is associated with the destination of the pulled command when the number of commands stored in each command queue is not more than a second threshold value which indicates a restart of queuing to the plurality of command queues.