©National Instruments Corporation4-1PCI E Series RLPM4ProgrammingThis chapter contains programming instructions for operating the circuitryon the PCI E Series boards.Programming the PCI E Series boards involves writing to and reading fromregisters on the board. Many of these registers belong to the DAQ-STC,and you will find a listing of these registers in the DAQ-STC TechnicalReference Manual. For a list of all board registers not on the DAQ-STC, seeChapter 3, Register Map and Descriptions, of this manual.The programming steps for analog input, output, digital I/O, and timingI/O are explained in the DAQ-STC Technical Reference Manual. Theseoperations are explained in terms of bitfields. A bitfield is defined as agroup of contiguous bits that jointly perform a function. Using bitfields hasthe advantage of establishing an efficient mapping technique to theunderlying hardware. Also, the programming style becomes very modular,and a functional description of every programming step iseasily understood.Because the DAQ-STC Technical Reference Manual has detailed,step-by-step programming instructions, this register-level programmermanual gives a series of common programming examples with referencesto the DAQ-STC Technical Reference Manual. The program for eachexample is presented as it is in the DAQ-STC Technical Reference Manual;that is, in terms of functions, with bitfields to be written for each function.To implement the function, you need to perform a memory write to or amemory read from the specified registers. The complete examples areprovided on the PCI E Series Register-Level Programmer ManualCompanion Disk.PCl Local BusThe PCI E Series boards are fully compatible with the PCI Local BusSpecification, Version 2.1 from the PCI Special Interest Group (SIG). ThePCI Local Bus is a high performance, 32-bit bus with multiplexed addressand data lines. The PCI system arbitrates and assigns resources throughsoftware, freeing you from manually setting switches and jumpers. You
