Hanna Instruments HI 720 Series - Manual (Page 29)

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Command Parameter Remarks
SET CNNP
1
P
2
C
1
C
2
C
3
C
4
Sets setup item C.NN (e.g. “r.01”) with
parameter P
1
P
2
C
1
C
2
C
3
C
4
(*) (not available
if the controller is in setup mode)
EVF not available Requests the event log file (not available if
the controller is in setup mode)
EVN not available Requests new event log file (not available if
the controller is in setup mode)
AER not available Requests active errors (always available)
CLS not available To start cleaning (for advanced cleaning;
always available)
CLP not available To abort cleaning (always available)
HLD not available To enter/exit the hold mode
(always available; password required)
KDS not available Same as DIAG key (always available)
KCD not available Same as CAL DATA key (always available)
KUP not available Same as up arrow key (always available)
KRG not available Same as right arrow key (always available)
KST not available Same as SETUP key (always available)
KCL not available Same as CAL key (always available)
KDW not available Same as down arrow key (always available)
KCF not available Same as CFM key (always available)
(*) C
1
C
2
C
3
C
4
are ASCII chars corresponding to the setup item content; P
1
is an additional
byte used fo r sign as follows:
P
1
= + if>0
P
1
= - if<0
When the sign is not used, set P
1
to “+”.
P
2
is used with particular meaning for the following items:
G.01: P
2
= 0 if range is 1999 μS/cm
P
2
= 1 if range is 19.99 mS/cm
P
2
= 2 if range is 199.9 mS/cm
G.02: P
2
= 0 if range is 1000 ppm
P
2
= 1 if range is 10.00 ppt
P
2
= 2 if range is 100.0 ppt
P
2
= 3 if range is 1000 ppt
RS485 Protocol for HI 720
Commands are composed of four parts: address, command identifier, param-
eter, end of command. The end of command corresponds to the CR char (0x0d).
Some commands are used when the master is requesting information from the
controller, others when the master wants to set a parameter in the process memory
(RAM or EEPROM).
The master software must send the command string with a maximum delay of
20 ms between each character.
If the general password has not been entered, the program on the master must
not allow setting commands other than keyboard or cleaning start/stop com-
mands. After the general password recognition through the “PWD” command,
a 1-minute time-out is let before the process meter locks again, i.e. if the PC
program waits for more than 1 minute between two subsequent commands, the
second one is not fulfilled and the “PWD” command must be issued again.
This is the complete list of available commands:
Command Parameter Remarks
MDR not available Requests the software code for model
identification (always available)
HOP not available Requests hardware options
STS not available Requests the instrument status (relays, LEDs,
configuration change flag, etc.)
ECR not available Requests last acquired conductivity, TDS or
concentration value (always available, but
the retrieved value is the last measurement
performed when the controller was in idle
or control mode)
TMR not available Requests last acquired temperature value
(always available, but the retrieved value is
the last measurement performed when the
controller was in idle or control mode)
CAR not available Requests last calibration data
(always available)
GET CNN Requests setup item C.NN
(e.g. “r.01” ; always available)
PWD C
1
C
2
C
3
C
4
Sends the general password (always available)