Pressure Systems 98RK-1 - Manual (Page 37)

Pressure Systems, Inc. 98RK-1 & 9816 User’s Manual©
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The error response consists of the letter ‘N’ (for NAK, or negative acknowledge), followed by a
2-digit hexadecimal error code. The following table lists the error codes that can be returned
from a 9816 NetScanner
™ System module:
CODE MEANING
00 (Unused)
01 Undefined Command Received
02 Unused (by TCP/IP)
03 Input Buffer Overrun
04 Invalid ASCII Character Received
05 Data Field Error
06 Unused (by TCP/IP)
07 Specified Limits Invalid
08 NetScanner error: invalid parameter
09 Insufficient source air to shift calibration valve
0A Calibration valve not in requested position
The Acknowledge response is returned from a module when a command is received that
requires no data to be returned, and no error is detected. It indicates successful parsing and
execution of the last received command. It consists of the letter ‘A’ (for ACK, or acknowledge).
The Acknowledge with Data response is returned when a module receives a command
requesting data. Model 9816 modules will typically return only the requested data values, each
preceded by a space character (except for format 7). No 'A' (acknowledge) letter begins this
data response. Data are returned for the highest requested channel number first. Data for
lower requested channels follow in reverse order (e.g., P&S, then 16-1).
3.1.4.1
Interpreting Offset Values (Re-zero Calibration Adjustment)
When a Model 9816 module is instructed to execute the command Calculate and Set Offsets
('h'), a datum corresponding to the calculated offset correction term (or coefficient) is returned
for each affected channel. Each such coefficient value is stored internally, and will be
subtracted in all subsequently calculated data conversions, to correct for zero drift effects. The
command only returns them in the response (in current engineering units (EU) of pressure near
0.0) to allow the user to make reasonableness checks on them. The Read Internal
Coefficients ('u') command will return them on demand.
3.1.4.2
Interpreting Gain Values (Span Calibration Adjustment)
When a Model 9816 module is instructed to execute the command Calculate and Set Gains
('Z'), a datum corresponding to the calculated gain correction term (or coefficient) is returned
for each affected channel. Like the offset coefficient, each gain coefficient is stored internally,
and will be used in all subsequently calculated data conversions, to correct for gain change
effects. The command returns them in the response (as a unitless factor near 1.0) to allow the