waiting for dequeue in the queue is not allowed to be dequeue in the kth cycle the data in the register may be transmitted based the number of concatenation units transmittable by the bus per cycle until the second back pressure count value in the gth cycle is smaller than or equal to the second preset threshold and then it is determined that in a g 1 cycle the cell waiting for dequeue can be dequeued the g is a positive integer greater than k according to an embodiment the step of scheduling the cell waiting for dequeue to be dequeued may include the following steps a head pointer a sub head pointer and a dequeue sub pointer of a corresponding fifo queue are acquired based on a dequeue port number a cache unit number range and number of cache units to be read may be calculated based on a number of the cache units occupied by the cell waiting for dequeue in the queue and the dequeue sub pointe then data in the cache units occupied by the cell waiting for dequeue is recombined into one cell and the dequeue sub pointer is updated to be a sum of a previous dequeue sub pointer and the number of the cache units occupied by the cell when the sum is greater than n the dequeue sub pointer is updated to be the sum minus n when the sum of the previous dequeue sub pointer and the number of the cache units occupied by the cell is not greater than n the head pointer will not be updated.