that data is processed by the floating point board the determination of which of fifo circuits 191 and 192 to empty is done by input control circuit 196 it has intelligence to determine how many strings are active and it also monitors the amount of data in each of fifo circuits 191 and 192 to determine which one has to be emptied first to ensure that no data overflow conditions occur it also will provide the control to two to one selector circuit 194 which reflects which fifo circuits 191 or 192 has been selected by input control circuit 196 there are two output lines of concern the first line goes to a format register 198 this is the serial data which has been sent over from dc offset filter board 70 the serial data also has an address associated with it this address is used to determine whether the data sample that has been received is from an actual data channel or is status information from analog modules 22 and 24 this address information feeds address register 220 which converts it from a serial to a parallel format the parallel output of address register 220 is an input to address prom 222 which generates output lines signifying whether it is status or data address prom 222 may also produce a format bit.