Communication specifications

NOTE:

The RS-232 communications interface will automatically turn itself off when not transmitting.

Supported formats:

RS-232 full duplex only (default)

RS-485 half duplex

Choice of 8 bit, no parity or 7 bit, even parity

1 stop bit

Parity checking is not supported as most communication protocols used by the AtmosVue 30 have built in checksums, as well as checks that communications have been understood.

Serial setting:

8N1

Supported data rates:

1200 bps, 2400 bps, 9600 bps, 19200 bps, 38400 bps (default), 57600 bps, 115200 bps

Serial setting:

8N1

RS-232 communications

RS-232 input threshold, low:

0.8 V (minimum), 1.5 V (nominal)

RS-232 input threshold, high:

2.0 V (nominal), 2.4 V (maximum)

RS-232 input absolute maximum:

±15 V

RS-232 input resistance:

12 kohm

RS-232 output voltage:

0.4 to 4.4 V

RS-485 communications

RS-485 input threshold voltage:

±0.2 V

RS-485 output (unloaded):

5 V

RS-485 output (load 5 ohm):

2 V

Maximum voltage at any terminal:


±7 V; the sensor ground and any RS-485 equipment ground cannot be further apart than this voltage. The sensor ground (pin 1) on connector B can be connected to the ground of the host equipment to reduce parasitic currents.