S=
Serial Number
The
S
erial number command reads the factory set PPT serial number. If the response has an ‘!’
character instead of ‘=‘, there was an EEPROM parity error.
Inquiry: *dd
S=
RS-485 type only
In multidrop bus configuration only this command must be used to identify a PPT for address
assignment. Command *99
S=
ssssssss, where ssssssss is the 8 character serial number of the PPT
(in this case the leading zeros of the serial number must be used because the identification match is
made on all 8 ASCII characters—not the decimal value of the serial number), identifies the PPT for
identification address assignment. The address assignment is then performed by a *99
ID
nn com-
mand, where nn is the address.
Note
: If two PPT units on a RS-485 bus have the same ID then you can use the sequence
below to re-assign ID numbers
Action:
*99WE
*99S=
ssssssss
(this allows the PPT to accept the next *99ID command)
*99WE
*99ID
=nn (this assigns the PPT #ssssssss the ID number ‘nn’)
Where:
ssssssss
is the PPT serial number with sufficient leading zeros to provide 8 characters.
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