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Proton Products InteliSENS PD30 Instruction Manual (Issue 1a)
P
ROTON STANDARD PARAMETER ACCESS PROTOCOL
This protocol provides access to individual parameters or blocks of parameters and is typically used in
a production environment where the gauge is connected to a computer, PLC or similar device.
The parameters consist of 16-bit words (DW) and are divided into input and output groups:
Input parameters may be read and written and are used to configure the gauge.
Output parameters are read only and provide access to gauge status and measurement data.
They may be requested to stream continuously from the gauge.
The Proton standard protocol RS-232 data format is:
Number of data bits
Parity
Number of stop bits
Flow control
Default baud rate
8
None
1
None
115200 bit / s
P
ARAMETER WORD FORMATS
Bit pattern words
Words defined as a bit pattern are formatted as 4 characters representing bits 15
– 0 in hexadecimal
(0
– 9; A – F in capitals only), with bit 15 as the most significant bit. Unused or reserved bits are set to
binary zero.
Numerical value words
Words defined as a numerical value are formatted as a string of characters representing the value in
decimal format, complete with sign where appropriate, but with no decimal point and leading zeros
suppressed.
Double length words
Double word length parameters are accessed by the address of the first word only. The data in both
words is formatted together as a single string.
R
EADING INPUT PARAMETERS
If a PC-based terminal program (such as MS Windows HyperTerminal) and keyboard is being used
for RS-232 communication with the gauge, then the carriage return followed by line feed (<CR><LF>)
sequence of commands can be replaced by a single press of the ‘Enter
↵
’ key.
Reading a single input parameter
Use the following request format to read a single input parameter value:
Request
format
?[Input parameter number]<CR><LF>
Response
format
[Input parameter value]<CR><LF>
Reading a block of input parameters
Use the following request format to read a contiguous block of input parameter values:
Request
format
?[Input parameter number][Space][Number of parameters]<CR><LF>
