Despatch P1400+ Temperature Controller - Manual (Page 71)

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Table 24. ASCII Parameter Key
{S} is the Start of Message character L (Hex 4C) or R (Hex 52).
L is used for Controllers; R is used for Profilers.
{N} is the slave device address (in the range 1 - 99); addresses 1 - 9 may be represented
by a single digit (e.g. 7) or in two-digit form, the first digit being zero (e.g. 07).
{P} is a character which identifies the parameter to be interrogated/modified.
{C}
is the command (Refer to the Serial Communications Application Layer
information for each Model Group )
# indicates that {DATA} is to follow (Hex 23)
{DATA} is a string of numerical data in ASCII code (refer to the Data Element table below)
P is the Program Number
S S is the Segment Number (01 to 16)
* is the End of Message Character (Hex 2A)
No space characters are permitted in messages. Any syntax errors in a received message will cause
the slave instrument to issue no reply and await the Start of Message character.
Table 25. ASCII Data Element – Sign/Decimal Point Position
{DATA} Content Data Format Description
abcd0 +abcd Positive value, no decimal place
abcd1 +abc.d Positive value, one decimal place
abcd2 +ab.cd Positive value, two decimal places
abcd3 +a.bcd Positive value, three decimal places
Abcd5 - abcd Negative value, no decimal place
Abcd6 - abc.d Negative value, one decimal place
Abcd7 - ab.cd Negative value, two decimal places
Abcd8 - a.bcd Negative value, three decimal places
(in the Data Content, abcd represents the data value, the last digit indicates data format)
Type 1 Message
L {N} ? ? *
This message is used by the master device to determine whether the addressed slave device is
active.
The reply from an active slave is
L {N} ? A *
An inactive device will give no reply.