The LMX2571-EP is programmed using several 24-bit registers. A 24-bit shift register is used as a temporary register to indirectly program the on-chip registers. The shift register consists of a data field, an address field, and a R/W bit. The MSB is the R/W bit. 0 means register write while 1 means register read. The following 7 bits, ADDR[6:0], form the address field which is used to decode the internal register address. The remaining 16 bits form the data field DATA[15:0]. While LE is low, serial data is clocked into the shift register upon the rising edge of clock. Serial data is shifted MSB first into the shift register when programming. When LE goes high, data is transferred from the data field into the selected active register bank. See Figure 6-1 for timing diagram details.