Picotest M3500A, Руководство пользователя

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Standard Event Register and the Questionable Data Register .
The Status Byte Register collects and records high-level summary
information which is reported in other register groups. With the following
diagram illustration, you would make themselves clear for the SCPI
status system. In addition, the Standard Event and the Questionable
Data Registers have event registers which belong to read-only registers
and report defined conditions in a multimeter. Bits are latched in the
event registers. As long as an event bit is set, subsequent state changes
will be ignored. Besides, bits in an event register are cleared
automatically by the commands, for example: *ESR?, STAT:QUES:EVEN?
or *CLS. Please note that the reset command (*RST) or device clear in
event registers won’t clear bits. To query an event register will return a
decimal value corresponding to binary-weighted sum of all bits set in the
register.
An enable register is readable and writable, and can define which bits in
the corresponding event register are ORed together to generate a single
summary bit. To query an enable register won’t clear it, as well the
command *CLS, but it can clear the bits in the event registers. And the
command STATus:PRESet will clear the questionable data enable
register. Moreover, to enable bits in an enable register, you have to write
a decimal value corresponding to the binary-weighted sum of the bits in
the register by your demands.
Binary Weights
2
º
= 1
2
¹
= 2
2
²
= 4
2
³
= 8
2
4
= 16
2
5
= 32
2
6
= 64
2
7
= 128
2
8
= 256
2
9
= 512
2
10
= 1024
2
11
= 2048
2
12
= 4096
2
13
= 8192
2
14
= 16384
2
15
= 32768