Keri Systems SB-293 - Manual (Page 57)

Keri Systems, Inc. Technical Reference Manual – PXL-250 and SB-293
Revision 5.5 P/N: 01836-004 Page 57
9.10 RS-232 Controller/PC Connection
The RS-232 serial port (see Figure 9-1 on page 39) provides a communication link
between the access control network of PXL-250 controllers and the host computer
running the Doors access control software. This link can be made one of two ways.
• Via a serial cable directly connecting the serial port of the master PXL-250
controller and the host computer.
• Via a set of modems making a remote connection between the master PXL-250
controller and the host computer.
The PXL-250 controller will automatically determine the communication method it
needs to use on power up (direct-connect or modem) and configures itself accordingly.
In either case, connecting cables are available from Keri Systems (PXL to PC or PXL
to Modem), or you may make your own cables. If you make your own cables, please
install housings on each connector to protect the wire/connector pin junctions.
NOTE: Keri Systems requires using modems from the same manufacturer at both the
host computer and the access control network. This eliminates the possibility of
incompatibilities between modems from two different manufacturers from affecting the
communication between access control network and Doors software. Keri Systems
cannot be held responsible for problems caused by incompatibilities between modems
from two different manufacturers.
NOTE: When using 56K modems to communicate with remote access control
networks, all modems must use the same communication format - either X2 or Flex.
Incompatibilities between the two formats make some modems of one format
incapable of reliable communication with modems of the competing format. Modems
using the V.90 specification are compatible regardless of whether they are from an X2
or Flex manufacturer.
NOTE: Do not use male/female gender change plugs or 25-pin to 9-pin adapters when
making RS-232 serial port connections, these devices may have internal wiring
changes that can disrupt communications when implemented in conjunction with the
Keri Systems serial wiring instructions. If you must use a gender changer plug, ensure
it is a "straight-through" plug.