Motorola R-2001A Service Manual page 206

22-1. INTRODUCTION
22.2. The IEEE Interface Option enables the use of the Communications System Analyzer as a
programmable measurement instrument. When combined with a suitable programmable controller and
applications software, the major functions of the analyzer can be controlled or monitored via an IEEE-488
standard digital interface. Thus, repetitive test routines can be performed and the data recorded quickly and
accurately with little operator interaction.
22-3. The interface characteristics conform to the specifications of the IEEE Standard Digital Interface for
Programmable Instrumentation (IEEE Standard 488) which defines both the electrical and the mechanical
interface. Control protocol is also defined by the specification. Control commands which are unique to the
analyzer are described in detail in the following paragraphs of this section.
22-4. The controller for this application should be capable of reading and writing ASCII and control
characters from and to the bus in accordance with the 488 specification. Application software is the user's
responsibility as dictated by the controller selected, although interface and application assistance is available
from Motorola.
22-5. The IEEE option package consists of an IEEE Interface module (A8) with a rear panel connector, an
electrically programmable RF attenuator in place of the step attenuator on the RF Input Module (AH), a
fourteen position rotary switch on the front panel in place of the step attenuator shaft, and one additional ROM
memory 1C on the Processor module (A9).
22-6. While in the local mode the IEEE-488 equiped system operates and performs the same as a standard
system, except the maximum RF output level is reduced to +11 dBm from +13 dBm. However, when the Remote
Enable (PEN) line on the IEEE Bus is activated many of the front panel controls are disabled and their functions
placed under bus control. Refer to table 22-1 for a listing of those functions which can be controlled or
monitored via the 488 Bus.
SECTION 22
IEEE — 488 BUS CONTROL
22-1