User port (RS-485) commands - HMT130

HMT130 User Guide

Document code
M211280EN
Revision
D
Language
English (United States)
Product
HMT130
Document type
User guide

The RS-485 interface enables communication between RS-485 network and HMT130 transmitter. The RS-485 interface is not isolated.

Set the RS-485 interface by using the commands listed in this section. Other serial line commands are presented in List of serial commands.

Table 1. SERI command
seri [b p d s]<cr>
where
b
bit rate (1200, 2400, 4800, 9600, 19200, 38400, 57600, 115200)
p
parity (n = none, e = even, o = odd)
d
data bits (7 or 8)
s
stop bits (1 or 2)

Use the seri command to input RS-485 bus settings. This command affects the serial port where the settings are given (service port or user port).

Table 2. SERI2 command
seri2 [b p d s]<cr>
where
b
bit rate (1200, 2400, 4800, 9600, 19200, 38400, 57600, 115200)
p
parity (n = none, e = even, o = odd)
d
data bits (7 or 8)
s
stop bits (1 or 2)
The seri2 command is equivalent to the seri command, but it affects only the user port settings. The main purpose of the command is to change the user port settings via the service port.
Table 3. ECHO command
Syntax Description
echo [x]<cr>
where
x
ON or OFF (default=OFF)
Use the echo command to enable/disable echo of characters received over the serial line.
When using a 2-wire connection, echo must be always disabled (OFF).
Table 4. SMODE command
smode [xxxx]<cr>
where
xxxx
STOP,RUN or POLL
  • STOP: measurements are output only when the send command is given, all commands can be used
  • RUN: measurements are output automatically, only the s command can be used to stop the output
  • POLL: measurements are output only when the send [addr] command is given specifying a polled transmitter's address
Use the smode command to set the default serial interface mode.
When several transmitters are connected to the same line, each transmitter must be entered an own address in the initial configuration, and POLL mode must be used.
Table 5. SDELAY command
Syntax Description
sdelay [delay]<cr>
where
delay
RS-485 turnaround time in milliseconds, range 0 … 1000 ms.
Use the sdelay command to set the answer delay (RS-485 turnaround time) for the User Port.
Example:
>sdelay 100
Turnaround time     : 100
>
Table 6. INTV command
Syntax Description
intv [n xxx]<cr>
where
n
1 ... 255
xxx
S, MIN or H

Use the intv command to set the RUN mode output interval.

The time interval is used only when the RUN mode is active. Setting the RUN output interval to zero enables the fastest possible output rate.

Example: set output interval to 10 min:
>intv 10 min
Output intrv.    :    10 min
> 
Table 7. ADDR command
Syntax Description
addr [aa]<cr>
where
aa
address (0 ... 99) (default = 0)
Use the addr command to view or input the RS-485 transmitter address.
Addresses are required only for POLL mode (see Table 3.
Example: Configure the transmitter to use address 99 (after the ?prompt)
>addr
Address : 2 ?  99
>
Table 8. SEND command
Syntax Description
send [aa]<cr>
where
aa
address of the transmitter (set with the addr command)
Use the send command to output the reading once in POLL mode.
Table 9. OPEN command
Syntax Description
open [aa]<cr>
where
aa
address of the transmitter (set with the addr command)
When all transmitters on the RS-485 bus are in POLL mode, the open command sets one transmitter temporarily to STOP mode so that other commands can be entered.
Table 10. CLOSE command
Syntax Description
close<cr>

The close command switches the transmitter back to the POLL mode.

Example:
>OPEN 2      // (opens the line to transmitter 2, other transmitters stay in POLL mode)
>CRH      // (for example, calibration performed)
...
>CLOSE      // (line closed)