Condec DLR334 User Manual
Page 6
PAGE 6
74845
RESPONSE
VALID ENTRY INVALID ENTRY CAN NOT PERFORM
(NONE) =
(NONE)
(NONE)
(NONE)
(ECHO) =
:
:NAK
:NAC
(ACK) =
:ACK
:NAC
6.0
CHECK OPTION:
The check option is setup in the print duplex mode of port 1. It can be applied to the duplex serial in
the RS485 mode or in non addressable mode.
If check setup is set for ‘NONE’ (OFF), no characters are transmitted for check.
Checksum: if checksum is selected the check consists of two ASCII characters.
♦
All ASCII characters including the starting character and terminating character preceding
the checksum is included in the checksum.
♦
The ASCII characters are binary summed (not including the parity bit).
♦
The least significant byte is divided into four bits each “nibbles” and 30H is added to
each. Therefore a sum of 5EH will be transmitted as 35H and 3EH or ‘5>’.
Xor: if exclusive or is selected the check consists of two ASCII characters.
♦
All ASCII characters preceding the checksum are exclusively or’ed together.
♦
The check byte is then calculated to give a result of zero when it is exclusively or’ed in.
♦
The check byte is divided into four bits each and 30H is added to each.
7.0
RS485:
The RS485 protocol is the same as the standard duplex except the two character destination address
and two character origin address is included after the starting character.
The host computer’s address is fixed at ‘00’ and the DLR address can be set between 1 and 98.
When the setup is not set for the RS485 mode the RS485 transceiver is set for transmit only (RS422
applications).
8.0
COMMAND CODE SUMMARY:
The Response is shown in the ‘Ack/Nak’ mode.
The ‘D’ column represents the data character length including the ‘|’ seperator but not the ‘{‘or’}’
brackets.
COMMAND CODE SUMMARY TABLE II
COMMAND
RESPONSE
D
DESCRIPTION
GENERAL:
ZED
ACK
-
Zero.
TAD
ACK
-
Tare. ;later
WEIGHT/PRESSURE/RATE DATA RECALL:
PDR
PDR
{pr,units,par,stat}
11
Display data recall.
PGR
PGR
{pr,units,par,stat}
11
Pressure recall.
PVR
PVR
{pr,units,par,stat}
11
R.P.M. recall
PHR
PHR
{pr,units,par,stat}
11
HP recall
PNR
PNR
{pr,units,par,stat}
11
∆T recall. ;later
PPR
PPR
{pr,units,par,stat}
11
Max data recall.
PMR
PMR
{pr,units,par,stat}
11
Min data recall.
STATUS RECALL:
PSR
PSR
{stat}
1
Pressure status recall (motion, etc.)
MSR
MSR
{units,mode}
3
Unit/mode status recall.
ISR
ISR
{I1|I2}
3
Input status recall.