Access Mode; Vmebus Base Address; Figure 3-2. Access Selection - National Instruments Corporation GPIB-1014P User Manual

Section Three

Access Mode

The GPIB-1014P can be configured to allow Supervisor (privileged) or Supervisor-and-User (non-
privileged) access using hardware jumper W2 as shown in Figure 3-2. To configure the board for
privileged access only, place the jumper on the side labeled S as shown in Figure
3-2a. To configure the board for non-privileged access, place the jumper on the side labeled NP as
shown in Figure 3-2b. The default setting for the GPIB-1014P is for non-privileged access. In the
Supervisor (privileged) mode, the GPIB-1014P only responds to Address Modifier (AM) code 2D.
In the Supervisor-and-User (non-privileged) mode, the board responds to AM codes 2D or 29.
(Refer to the ANSI/IEEE Std. 1014-1987, IEEE Standard for a Versatile Backplane Bus:
VMEbus for more information on Supervisor and Non-privileged modes.)

VMEbus Base Address

The address space required by the GPIB-1014P consists of one block of 16 consecutive byte
addresses. The GPIB-1014P responds only to AM codes that indicate short (16-bit) addressing
(See Access Mode previously in this section). The GPIB-1014P decodes the 12 most significant
address bits (A04 through A15) as the base address. The Talker/Listener/Controller (TLC)
internally decodes the Register Select signals, which are address bits A01 through A03.
© National Instruments Corporation
NP
•
I/O W2
S
a. Supervisor only
(Privileged)

Figure 3-2. Access Selection

NP
I/O W2
•
S
b. Supervisor-and-User
(Non-privileged)
3-3
Configuration and Installation
GPIB-1014P User Manual