RayTek LineScanner MP150, Руководство по протоколу

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Transmission of Temperature Lines
MP150 Protocol
Rev. B4 Aug 2019
15
2 Bytes for current output 3 (LSB first!)
Triggerbyte = one byte which is 1 if the external trigger pin is active, 0 otherwise
Checksum
= two-byte check sum (low, high), calculation starts after FrameStart
4.4.3 The Checksum of a Line or Snapshot
The Checksum of a line or snapshot is calculated as the sum of all eight-bit-characters, starting after
FrameStart. The sum is limited to a 16-bit number
– so it should be cut (in C code: sum &= 0xFFFF).
4.4.4 MP40 Line Modes
LM = 0: no [Sektorinfos] to Line Transfer
LM = 1: [Sektorinfos] contains Sector Values
LM = 2: [Sektorinfos] contains Zone Values
LM = 5: Sector Values (like LM =1) with bit 15 = Sector Alarm, bit 14 = serial Alarm
LM = 6: Zone Values (like LM =2) with bit 15 = Zone Alarm, bit 14 = serial Alarm
Taking the composition from the preceding sections as basis these modes omit the elements
[FrameStart], [Triggerbyte] and [Checksum].
4.4.5 MP50 Line Modes
LM = 8 ... F
hex
differ from line modes 0 ... 6 in providing the additional framing. They should be used at
least for the communication via RS485. (Unlike Ethernet the RS232 itself has no mechanism against
communication errors.)
4.4.6 MP150 Line Modes
4.4.6.1 Line Mode 11
hex
LM = 11
hex
: the six bytes of the traditional sector values are changed in their contents:
•
previous current output 1:
internal temperature in hundredth of °C (MSB first!),
•
previous current output 2:
If background temperature compensation via voltage input is configured then it contains the
background temperature (as integer in °C) calculated from the voltage, otherwise it contains
the voltage. This field may be extended if the functions of the voltage input get extended
– so
please use it in conjunction with its configuration!
•
previous current output 3:
error bits (see section 3.4
Error Handling , page 11)
Note: Error bit 31 and 30 are right shifted 16 bits, because the field here only consists of 16
bits, in contrast to the original error value with its 32 bit.
4.4.6.2 Line Mode 12
hex
LM = 12
hex
changes the first 2 bytes of LineMode 11
hex
from the internal temperature (it is already
contained with less resolution) to a snapshot/line counter:
Sectorinfos =
2 Bytes for snapshot/line counter
2 Bytes for background temperature / voltage input
2 Bytes for error bits (see section 3.4
Error Handling , page 11)