Status Reporting System - Tektronix MTD200 User Manual

Mpeg test decoder

Table of Contents

Status Reporting System

Structure of an SCPI

Status Register

MTD200 MPEG Test Decoder User Manual

The status reporting system (see Figure 5–4 on page 5–52) stores all information

on the current operating status of the instrument and on errors. The information

is stored in the status register and in the error queue. The contents of the status

registers and of the error queue can be queried via remote control.

The information is hierarchically structured. The topmost level is formed by the

Status Byte Register (STB) defined by IEEE 488.2 and the associated mask

the Standard Event Status Register (ESR), which is also defined in IEEE 488.2,

and the associated mask register Standard Event Status Enable (ESE) as well as

from the SCPI–defined STATus:OPERation and STATus:QUEStionable

registers, which contain detailed information on the instrument.

The output buffer contains the messages returned by the device to the controller.

It is not part of the status reporting system, but since it determines the value of

the MAV bits in the STB, it is also shown in Figure 5–4 on page 5–52.

Each SCPI register consists of five registers of 16 bit each and with different

functions (see Figure 5–3). The individual bits are independent of each other.

Each hardware status is assigned a bit number which is the same for all five

registers. Bit 4 of the STATus:OPERation register, for instance, is assigned in all

five registers to the "MEASuring" action. Bit 15 (the most-significant bit) is set

to zero in all SCPI status registers. Thus the contents of the registers can be

processed by the controller program as a positive integer.

15 14 13 12

Figure 5–3: Status Register model

Remote Control

to next higher register

Summary bit

& = logic AND

= logic OR of all bits

5–49

Table of Contents

Do you have a question about the MTD200 and is the answer not in the manual?