ROTRONIC HC2 - Manual (Page 13)

E-M-HC2 Probes-V1_26
Rotronic AG
Bassersdorf, Switzerland
Document code Unit
HygroClip 2 (HC2) Humidity Temperature
Probes: User Guide
Instruction Manual
Document Type
Page 13 of 31
Document title
© 2009-2013; Rotronic AG E-M-HC2 Probes-V1_26
3.5 Digital interface
The HC2 probe features a UART interface (Universal Asynchronous Receiver Transmitter) that allows two-way
communication with the probe. For connecting the HC2 probe to a PC, use any of the following digital adapter
cables AC3001, AC3002 or AC3005 (see document E-M-HC2-accessories). The probe can also be indirectly
connected to a PC using an instrument from the ROTRONIC program.
The ROTRONIC HW4 software (version 2.1.0 or higher) allows full access to the following:
 Measurement data (humidity and temperature) and calculated parameter (dew or frost point)
 Probe information: name, RS-485 address, humidity sensor status, etc.
 Probe alarm functions
 Probe data logging function
 Probe calibration and probe adjustment functions
 Probe configuration
The ROTRONIC HW4 software (version 3.3.0 or higher) allows full access to the following:
 Firmware update of HygroClip probes
Communication protocol options
The probe measurement data can be read without having to use the ROTRONIC HW4 software. Starting with
firmware version 1.3, the HC2 probe offers the following communication protocol options (ASCII) which can be
selected by connecting the probe to a PC running the ROTRONIC HW4 software (version 2.1.1 or higher):
o
RO-ASCII: this is the standard (default) communication protocol used by all AirChip 3000 devices and by
the HW4 software. In principle, this protocol supports all of the AirChip 3000 functions but some of the
functions require a certain amount of computations to be carried out by an external device such as a PC.
o
Custom: this communication protocol can be used to provide compatibility of the HC2 probe with an
existing communication system. The Custom communication protocol is limited to reading measurement
data from the HC2 probe. Functions such as device configuration, humidity and temperature adjustment,
etc. are not supported. The Custom protocol is applicable to all AirChip 3000 devices with a digital interface
and allows RS-485 networking
o
I2C: The I2C protocol available with the HC2 probe does not allow the networking of devices and is limited
to a one way communication where the HC2 probe automatically sends data during each refresh interval
to an external device with I2C input.
When using either the RO-ASCII or the Custom protocol, the HC2 probe can be set to send data automatically
after each refresh cycle without requiring a data request. When this mode is enabled, the receiving device must
be listening at all times in order to get the measurement data.
For details, see document E-M-AC3000-CP