Fluid Components Intl ST51A, Инструкция по установке, эксплуатации и техническому обслуживанию

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ST51A/ST75A/ST75AV Mass Flow Meters OPERATION
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Table 15 – Command Status Bytes, Bit Assignments
Byte Bit
Error/Status Description
Communication Error Response Code (No Comm Error)
Byte 0
0 Reserved – Bit cleared to zero.
Command-Specific Response Code (0-127)
See Table 16 below.
1 Buffer Overflow – The message was too long for the
received buffer of the device.
2 Reserved – Bit cleared to zero.
3 Longitudinal Parity Error – The longitudinal parity
calculated by the device did not match the check byte at
the end of the message.
4 Framing Error – The stop bit of one or more bytes received
by the device was not detected by the UART (i.e., a mark or 1
was not detected when a stop bit should have occurred).
5 Overrun Error – At least one byte of data in the receive
buffer of the UART was overwritten before it was read (i.e.
the slave did not process incoming byte fast enough).
6 Vertical Parity Error – The parity of one or more of the bytes
received by the device was not odd
7 1: Set bit means byte represents communications error. 0: Cleared bit means byte represents response code.
Byte 1
Device
Status
0 Primary Variable Out of Limits – The PV is beyond its operating limit.
1 Non-Primary Variable Out of Limits – A device variable not mapped to the PV is beyond its operating limits.
2 Loop Current Saturated – The loop current has reached its upper (or lower) endpoint limit and cannot increase (or
decease) any further.
3 Loop Current Fixed – The loop current is being held at a fixed value and is not responding to process variations.
4 More Status Available – More status information is available via
Command 48, Additional Device Status Bytes
(next section).
5 Cold Start – A power failure or device reset has occurred.
6 Configuration Changed – An operation was performed that changed the device’s configuration.
7 Device Malfunction – The device detected a serious error or failure that compromises device operation.
Table 16 – Command-Specific Response Codes
Code (Class) Description Code (Class) Description
00 (Success) No command-specific errors 12 (Error) Upper Range value too low/Invalid mode
02 (Error) Invalid selection/Invalid Poll Address 13 (Error) Upper and Lower Range values out of
limit
03 (Error) Passed parameter too large 14 (Warning) Span too small/Status byte mismatch
04 (Error) Passed parameter too small 16 (Mode Error) Access restricted
05 (Error) Too few data bytes received 18 (Error) Invalid units code
06 (Misc Error) Device-specific command error 29 (Error) Invalid Span
07 (Mode Error) In Write-Protect mode 30 (Error) Command response truncated
09 (Error) Invalid date code/Configuration change
counter mismatch/Lower range value too
high/Incorrect loop current mode or value
32 (Error) Busy
10 (Error) Lower Range value too low 64 (Error) Command not implemented
11 (Error) Upper Range value too high/Loop
current not active (device in multidrop mode)
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