DH Instruments PPCH-G, Руководство по эксплуатации и обслуживанию

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3. OPERATION
Page 73 © 2007 DH Instruments, a Fluke Company
The default selection is
<1baro>
. With this selection, when AutoZ is ON, the
PPCH-G on-board barometer (see Section 3.5.7.2) is used as the AutoZ
reference (
P
std,0
) and AutoZ runs automatically whenever PPCH-G is vented.
The AutoZ function should be ON with
<1baro>
selected unless there is a
malfunction of the on-board barometer.
Select
<2entry>
to run AutoZ manually by entering the value of AutoZ reference
(
P
std,0
) as described in
“If the current measurement mode is absolute and a
Q-RPT is active”
above.
3.5.2 <2REMOTE>
 PURPOSE
To configure the PPCH-G COM1, COM2 and IEEE-488 (GPIB) communication ports. To test
COM1 and COM2 communications. To select remote programming communications format.
 PRINCIPLE
The PPCH-G has two RS-232 communications ports referred to as COM1 and COM2 and a
single IEEE-488 (GPIB) port. COM1 or the IEEE-488 port is for communicating with a host
computer (see Section 1), and COM2 is reserved for communicating with an external device
(i.e. an RPM4, a multimeter, etc.). These ports’ settings can be viewed and changed using
[SPECIAL]
,
<2remote>
.
PPCH-G has two remote communications formats, classic and enhanced. Which of these is
active can be selected.
A self test is supplied for RS-232 communications. The self test allows verification that the
PPCH-G RS232 ports (COM1 and COM2) are operating properly and that a valid interface
cable is being used.

OPERATION
To access the communications settings, press
[SPECIAL]
,
<2Remote>
.
Choice include:
<1COM1>
To view and edit COM1 settings (see Section 3.5.2.1).
<2COM2>
To view and edit COM2 settings (see Section 3.5.2.1.).
<3IEEE>
To view and edit IEEE-488 settings (see Section 3.5.2.2).
<4format>
To select remote programming command format (see Section 3.5.2.3).
<5RS232test>
To run the COM1 and COM2 communications test (see Section 3.5.2.4).
3.5.2.1 <1COM1, 2COM2>
The COMx ports can be set for specific communications settings. The settings
are baud rate, parity, data bits and stop bits. The available options are:
Baud
300, 600, 1 200, 2 400, 4 800, 9 600, 19 200, 28 800, 38 400
Parity
NONE, ODD or EVEN
Length
7 or 8
Stop Bit
1 or 2
The default is <2 400, E, 7,1> for both COM1 and COM2.
The user can also specify one or two termination characters as well as define
these characters. These are referred to as “Term1” and “Term2”. These define
the characters that mark the end of commands that are sent to the PPCH-G. The
PPCH-G looks for an ASCII(13) (carriage return) to terminate a received