BIRD THRULINE 4020 series, Инструкция

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RS-232 Interface
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Auto Baud
Auto Baud is used to automatically determine the correct transmission rate.
After setting DIP switches 1 through 5, follow the steps below to use auto
baud:
1. Set DIP swit ch es 6, 7, a n d 8 t o ON .
2. Con n ect a con t r oller t o t h e power m et er .
3. Tu r n t h e power m et er on .
4. Sen d t h e ch a r a ct er U (h exa decim a l 55) from the controller to the power
meter.
5. Wa it 1 secon d.
lays LISTEN, the baud rate has been
determined. If not, repeat steps 4 and 5.
If, after 30 seconds, the module cannot absolutely determine a baud rate, it
will choose a rate based on data acquired during the test.
Note:
Auto Baud is the only automatically chosen setting. Other items
such as parity and stop bits must be manually selected.
Talker-Only Mode
The Bird 4421 can be set up for manual operation while automatically sending
data to an output device (Talker-Only Mode). To do so, turn DIP switch 2 OFF
and cycle the power. TALK will be displayed.
In Talker-Only mode, pressing a button on the meter triggers a measurement.
When the measurement is complete, the information is sent to the bus.
Command Syntax
The Bird 4421 accepts two types of commands. General bus commands are
commands, such as Initialize (INT), that apply to any RS-232 interfaced
device. Device-dependent commands are specific to the 4421.
If an invalid command is sent to the unit, an error condition is placed in the
serial poll byte and the offending command is not executed.
A group of device-dependent commands can be sent as a single string as long
as like command categories are not re
This string sets up the 4421 to send no prefixes, read forward dBm, make one
Note:
Commands can be entered in either upper or lower case.
Note:
Only the last command entered of each category will be executed.
As a command string is processed by the 4421, each category of command is
stored in a separate location. Two commands of the same category will be
stored in the same location, so that the second will overwrite and erase the
first one.