count of the number of destinations waiting for the cell for example as shown in fig4 the first two words of a block of shared ram are used for switch specific parameters the next thirteen words are used for the data payload of an atm cell and the last word is used to indicate the number of destinations which should receive a copy of the cell pointers to the cells in a queue are similarly stored in sixty four byte blocks as shown in fig5 each block holds fifteen pointers and a pointer to the next block of fifteen pointers in a particular queue for example if there are forty one cells in a queue there will be forty one pointers stored in three blocks of shared ram the first block will store the first fifteen pointers and will contain a pointer to the location of the memory block containing the second fifteen pointers and the second block will store the next fifteen points and will contain a pointer to the location of the memory block containing the remaining eleven pointers from the foregoing it will be appreciated that blocks of pointers to individual cells in a queue are stored in a manner which is similar to a link list all of the pointers for each queue are indexed with a table entry which includes the addresses of the first and last pointers a count of the number of cells in the queue the queue limit and.