Register Sizes; Register Description Format; Terminology - National Instruments Corporation GPIB-1014P User Manual

Register Bit Descriptions
Register Name
Auxiliary Register B
Auxiliary Register E
Address Register 0
Address Register
Address Register 1
End Of String Register

Register Sizes

All program registers on the GPIB-1014P are 8-bit registers.

Register Description Format

The remainder of this section discusses each of the GPIB-1014P registers in the order shown in
Table 4-1. Each register group is introduced, followed by a detailed bit description of each register.
The individual register description gives the address, type, word size, and bit map of the register,
followed by a description of each bit.
The register bit map shows a diagram of the register with the most significant bit (bit 7 for an 8-bit
register) shown on the left, and the least significant bit (bit 0) shown on the right. A rectangle is
used to represent each bit. Each bit is labeled with a name inside its rectangle. An asterisk (*) after
the bit name indicates that the signal is active low. An asterisk is equivalent to an overbar.
In many of the registers, several bits are labeled with an X, indicating don't care bits. When a
register is read, these bits may appear set or cleared but should be ignored because they have no
significance. When a register is written to, these bit locations should be cleared.

Terminology

The terms set, set true, and set to one are synonymous. The terms clear, set false, set to zero, and
clear to zero are synonymous. The meanings of preset and reset are determined by the context in
which they are used. Bit signatures are written in uppercase letters.
The term addressed means the interface has been configured to perform a function from the GPIB
side, while the term programmed means that it has been configured from the VMEbus side. This
distinction is important to make because many functions, such as making the interface a Talker or
Listener, can be activated from either side.
GPIB-1014P User Manual
Table 4-1. GPIB-1014P Register Map (continued)
Address (Hex)
Base address + B
Base address + B
Base address + D
Base address + D
Base address + F
Base address + F
4-2 © National Instruments Corporation
Section Four
Type Size
Write only 8-bit
Write only 8-bit
Read only 8-bit
Write only 8-bit
Read only 8-bit
Write only 8-bit