![background image](http://html1.mh-extra.com/html/racal-instruments/1261b/1261b_user-manual_3120226048.webp)
1261B User Manual
Racal Instruments
Ó
1995
Configuring The 1261B 2-19
Connecting The
RS-232 Interface
Omit this procedure if your mainframe is not equipped with the
Enhanced Monitoring System (EMS).
The 1261B EMS
RS-232 port may be connected to a computer,
data terminal, or modem. Note that the RS-232 connector on the
1261B is a female, DB-09. If you do not intend to use the RS-232
port, omit this procedure.
Connecting To a
Computer, Data
Terminal, or
Modem
Use an RS-232 cable to connect J412 (9-pin female RS-232
connector) on the EMS rear panel to the RS-232 serial port on the
host controller. Refer to
Figure 2-13 Setting Up the Enhanced
Monitoring System (EMS) RS-232 Interface,
and to
Figure 2-14
RS-232 Cable Connections With a Computer, Data Terminal,
or modem.
RS-232 Flow
Control Method
Flow control is a means by which the host computer (or other
controller) may pace the flow of data coming from the 1261B EMS
Monitor so that the host controller has time to properly receive the
data. It also allows the 1261B EMS Monitor to pace commands
coming from the host computer so that the 1261B EMS Monitor
has sufficient time to execute the commands as they arrive.
The 1261B EMS RS-232 interface uses only “Software” flow
control or “XON/XOFF”. The host controller RS-232 flow control
must be set for “Software” or “XON/XOFF”.
With software flow control, as implemented in the 1261B EMS
Monitor, an RS-232 device that is receiving data may send an
XOFF character (ASCII 19
10
) to the sending device, commanding
the sending device to suspend data output. Later, when the
receiving device is ready for more data, it may send an XON
character (ASCII 17
10
) to the sending device, indicating that data
transmission may be resumed.
If your controller does not support flow control, it will not send or
respond to XON or XOFF characters and flow control will thus be
non-existent. Note that operating without flow control may
necessitate a slower baud rate in order to avoid data overrun
problems.
RS-232 Echo
Back
Considerations
The 1261B EMS Monitor will not echo back characters it receives
from the terminal. If you wish to see characters on your terminal
as you type them, set your terminal for “Local Echo”.
Artisan Technology Group - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisantg.com