11.5.2 Transmission Protocol
Basic condition
The LB 134 can send and receive.
The response time of the LB 134 is at most 2 seconds.
The transmission pattern is as follows:
* TDV FDV PRC MBR TYP ITM (MSK Data)*CSM*CR
<—Frame header———————>
<—————————Frame—————————>
where
(..) optional
TDV to device 0001 - 9999
FDV from device 9001 - 9008
PRC Process 00 - 03
MBR Member 00 - 06
TYP Type 00 - 03
ITM Item 00 - 30
MSK Mask on data 000000 - FFFFFF (not used)
Data data variable length
CSM checksum empty if no checksum
00 - FF 8 Bit checksum
CR carriage return
(Minimum length = 20, maximum 255)
The stars "*" must always be included, even if CSM is empty.
The LB 134 answers, with TDV and FDV being exchanged in the frame.
The LB 134 does not respond to request, if
1. TDV does not match address
2. FDV is not between 9001 and 9008
3. The transmission pattern is incorrect
4. The checksum is not correct
Explanation of the transmission frame
1. TDV = logical address of LB 134 set by user program
2. FDV = logical address of host computer, set in the user program. Always 9001.
3. PRC = process
00 = system level
01 = read radiological data
03 = digital outputs on/off, reset
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