Serial I/O Physical Connections; Com-B Rs-232/485 Configuration - Teledyne 300E Instruction Manual

Operating Instructions

6.8.2. Serial I/O Physical Connections

There are two connectors DB-9 connectors on the M300E Rear Panel. COM-A is
populated with a male connector, COM-B with a female connector. T-API offers two
mating cables one of which should be applicable for your use:
db-9 female to db-9 pin female – p/n WR000077. Allows connection of
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COM-A with the serial port of most personal computers.
db-9 female to db-25pin male – p/n WR0000024. Allows connection to
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the most common styles of modems (e.g. US Robotics Sportster).
Both cables are configured with straight through wiring and should require no
additional adapters.
To assist in properly connecting the serial ports to either a computer or a modem
there are activity indicators just to the side of both COM ports (presently only those
for COM-A are functional). When power is applied to the analyzer the red LED next
to the COM port should be illuminated. If it is not then there is something wrong
with the CPU or the wiring between the CPU and the motherboard.
Once a cable is connected between the analyzer and a computer or modem both
the red and green LED's should be ON. If not, for COM-A switch the DTE-DCE
switch on the rear panel to exchange the receive/transmit lines. If both LED's are
still not illuminated, check the cable to make sure it is constructed properly. For
COM-B it may be necessary to install or construct a null-modem (contact customer
service for information).

6.8.3. COM-B RS-232/485 Configuration

Delivered from the factory, COM-B is setup as a non-isolated, half-duplex RS-485
port with a 150 Ohm termination (see Table 6-16 for the pin out). It can be
reconfigured for RS-232 operation by a simple reconfiguration of the CPU card
(see Figure 3-6).
For RS-485 (default) the jumper on JP3 should be installed and switch 6 of SW1
should be set to the ON position. For RS-232 remove the jumper and set the
switch to OFF. JP3 is just to the right of CN5, which is the third connector from the
left on the top of the CPU card (as seen from the inside of the analyzer). SW1 is in
the middle of the CPU just to the right of the Disk-on-Chip. For non-terminated RS-
485 operation remove the jumper on JP3 but leave switch 6 in the ON position.
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