Campbell Hausfeld Serial I/O Interface SDM-SIO4 - Manual (Page 20)

SDM-SIO4 User Guide
3-4
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i[ ] Scan until any ASCII characters entered between the brackets are
encountered. The maximum number of characters between the brackets is 255.
Note that this filter does not remove the matched character from the buffer.
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n n Discard ‘n’ bytes. ‘n’ can be in the range of 0-255.
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N n Read ‘n’ bytes. ‘n’ can be in the range of 0-255 (not converted to
Campbell Scientific floating point).
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pn Hexadecimal byte should be here, n=number of bytes to convert (n=1 to
3 hex pairs) to Campbell Scientific floating point.
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rn Send the byte received to port ‘n’ for re-transmission. ‘n’ can be
1-4. The byte is removed from the receive buffer.
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s Stop the filter until commanded by the datalogger to restart.
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t[ ] Search for an exact string match between the [ ]. All ASCII characters
up to and including the matching string are removed from the receive buffer
before the next filter type starts.
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T[ ] Search for an exact string match between the [ ]. All ASCII characters
up to the matching string are removed from the receive buffer before the next
filter type starts. (Same as t[ ], except matching strings are not removed).
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u[ ] Convert ASCII floating point into Campbell Scientific floating point
format until the termination character/string between [ ] is seen. The
termination character is removed from the buffer.
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vn[ ] Convert ‘n’ ASCII hex pairs into Campbell Scientific floating point
format until the termination character/string between [ ] is seen. ‘n’ can be 1-3.
The termination character/string is removed from the buffer.
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wn[ ] Convert ‘n’-byte binary data into Campbell Scientific floating point
format until the termination character/string between [ ] is seen. ‘n’ can be 1-3.
The termination character/string is removed from the buffer.
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x This marks the start of a data set. A data set is a set of converted data for
the datalogger to collect. When this filter type is used the data in the data set is
only available to the datalogger when all parts of the data set have been
converted – see ‘X’, below.
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X This marks the end of a data set. This makes the data converted in the
data set available to the datalogger. This also means that data after this is
available to the datalogger as soon as the SDM-SIO4 has converted each
value. If the end of the data set is at the end of the filter string then this filter is
not required as the end of the filter string is always the end of a data set.
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z Flush the UART FIFO (serial port hardware buffer) and the Receive
buffer associated with the port that is using this filter type. This does not,
however, clear the converted data buffer.
As an example, take the following sensor output string:
battery 12.65V,current 12mA
The filter string might be:
i[b]n8Fi[c]n8F
Output to the datalogger would be 12.65 and 12 as Campbell Scientific floating
point numbers. This filter string works as follows:
1. i[b] waits for the trigger character ‘b’ of ‘battery’.