Riftek RF603 Series, Руководство пользователя

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Triangulation Laser Sensors, RF605 Series
RF605 [Revision 2.0] 10th January 2011 valid for sensors with serial numbers 11000 and higher
13
and then follows higher tetrad. When multi-byte values are transferred, the transmission
begins with lower byte.
The following is the format
of two ‗message‘ data bursts for transmission of byte:
DAT(7:0)
Byte 0 Byte 1
1 0 0 0 DAT(3:0) 1 0 0 0 DAT(7:4)
11.5.5. Answer
"Answer‘‘ is data burst that can be transmitted by ‗slave‘ in the course of the ses-
sion.
All messages with a message burst contain 1 in the most significant digit. Data in
a message are transferred in tetrads . When byte is transmitted, lower tetrad goes first,
and then follows higher tetrad. When multi-byte values are transferred, the transmission
begins with lower byte.
When ‗answer‘ is transmitted, the message contains:
SB-bit, characterizes the updating of the result. If SB is equal to "1" this
means that the sensor has updated the measurement result in the buffer, if
SB is equal to "0" - then non-updated result has been transmitted (see. Note
1, p.10.3.). SB=0 when parameters transmit;
two additional bits of cyclic binary batch counter (CNT). Bit values in the
batch counter are identical for all sendings of one batch. The value of batch
counter is incremented by the sending of each burst and is used for formation
(assembly) of batches or bursts as well as for control of batch losses in re-
ceiving data streams
.
The following is the format of two ‗answer‘ data bursts for transmission of byte:
DAT(7:0)
Byte 0 Byte 1
1 SB CNT(1:0) DAT(3:0) 1 SB CNT(1:0) DAT(7:4)
11.5.6. Data stream
‗Data stream‘ is an infinite sequence of data bursts or batches transmitted from
‗slave‘ to ‗master‘, which can be interrupted by a new request. In transmission of ‗data
stream‘ one of the ‗slaves‘ fully holds data transfer channel, therefore, when ‗master‘
produces any new request sent to any address, data streaming process is stopped. Also,
there is a special request to stop data streaming.
11.5.7. Request codes and list of parameters
Request codes and list of parameters are presented in Chapter 13.
12. Analog outputs
Changing of the signal at analog output occurs in synchronism with the changing
of the result transferred through the bit-serial interface
12.1. Current output
4…20 mA
The connection scheme is shown in the figure. The value of load resistor should
not be higher than 500
Ом. To reduce noise, it is recommended to install RC filter be-
fore the measuring instrument. The filter capacitor value is indicated for maximum sam-
pling frequency of the sensor (9,4 kHz) and this value increases in proportion to the fre-
quency reduction.