Honeywell HC900 - Connecting the HC900 Controller to Modbus device(s)

140 HC900 Process & Safety Controller User and Installation Manual Revision 6
21 April 2017
Modem configuration examples
Below are procedures for setting up the following commercially available modems:
 3Com US Robotics 56K Data/Fax External Modem
 Zoom 56K Dualmode External Modem (page 142)
 Best Data 56SX Data Fax External Modem (page 143)
 SixNet VT-MODEM Industrial External Modem (page 144)
3Com US Robotics 56K Data/Fax External Modem
Step
Action
1
Ensure that the switches are set to the factory settings:
Switch
Setting
Position
Function
1
OFF
UP
Normal DTR operations
2
OFF
UP
Verbal (word) results
3
ON
DOWN
Enable result codes
4
OFF
UP
Displays keyboard commands
5
ON
DOWN
Disables auto answer
6
OFF
UP
Modem sends CD signal when it connects with another
modem
7
OFF
UP
Loads Y0-Y4 configuration from user-defined
nonvolatile memory (NVRAM)
8
ON
DOWN
Enables recognition (smart mode)
2
Connect the modem to a PC. If your computer’s RS-232 port has a 25-pin connector, use a
DB-25 male to DB-25 female RS-232 cable. If your computer’s RS-232 port has a 9-pin
connector, use a DB-25 male to DB-9 female modem cable.
3
Power-up the modem.
4
Run a serial communication port program such as Hyperterminal.
5
Within the communication program, select the port to which the modem is connected.
6
Configure the port to these settings:
baud rate = 1200, 2400, 4800, 9600, 19200, 38400, 57600 (Must match Baud Rate
configured in HC900 Controller)
data bits = 8
parity = none
stop bits = 1
flow control = none
7
In the program's terminal window, restore factory defaults by keying-in the following command
string:
AT &F0
Then, press the ENTER key.
The modem should respond with OK.