Product data

Troubleshooting & Misc.
Basic Serial Communication Problems
If you are having problems communicating with a Morningstar product while using a serial to se-
rial (or serial to RJ-11) connection:
Make sure the device is powered with a battery or power supply. The device cannot com-•
municate without power.
Verify that the serial cable is not a Null Modem or crossover cable.•
Verify that no other programs or managers are attempting to use the same serial port.•
Check to make sure your COM port settings are correct. (Section 5.3.3)•
If using the controller’s Ethernet connection as well, remove the Ethernet cable.•
Check the serial cable for continuity using a multimeter. The cable should have continuity •
fromPin1<->Pin1,Pin2<->Pin2,etc.Ifpossible,tryanothercable.
Shut down and restart PC. Try to reconnect.•
Try another PC.•
Serial Port Power with 3rd Party Devices
The built-in DB-9 serial ports on all Morningstar products are opto-isolated from the rest of the
unit, meaning that power must be applied to the port via the serial cable connection. PC serial
portswillprovidethispowerontheproperpinswithoutmodication,however,otherproducts
(such as Ethernet to serial converters, cellular modems, and wireless radios) may not provide
proper power.
When choosing equipment that will connect via RS-232 to your Morningstar unit, you should
know what port power is needed. Figure 37 is a basic pin diagram of a Morningstar DB-9 port:
Figure 37. Morningstar DB-9 serial port pinout.
Troubleshooting & Misc.11.0
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