Campbell Hausfeld SDM-CAN Manual Do Utilizador

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Section 3.  Programming CR10X, CR7 and CR23X 
  
3.5 Program Examples 
Examples of specific instructions which decode/encode CAN data are shown in 
Appendix C. This section gives some general examples of program constructs 
which show the general principles of operation. 
3.5.1  Reading CAN Data
 
The following example reads a 16 bit engine speed value from a CAN network 
running at 250K baud. 
;{CR23X} 
*Table 1 Program 
  01: 1.0       Execution Interval (seconds) 
 
;Retrieve Data from CAN network  
 
1:  SDM-CAN (P118) 
 1: 0        SDM Address 
 2: 4        Time Quanta 
 3: 5        Tseg1 
 4: 2        Tseg2 
 5: 1024     ID Bits 0..10 (-- for 11-bit CAN ID) 
 6: 7680     ID Bits 11..23 
 7: 12       ID Bits 24..28 
 8: 2        Rx, unsigned int, LSB 1st 
 9: 33       Start Bit No. 
10: 16       No. of Bits 
11: 1        No. of Values 
12: 1        Loc [ Eng_Spd   ] 
13: 0.125    Mult 
14: 0.0      Offset 
 
*Table 2 Program 
  02: 0.0000    Execution Interval (seconds) 
*Table 3 Subroutines 
 
End Program 
 
The above example uses the J1939 standard to define the ID 
parameter and value position in the data frame. Please refer to 
Appendix C for an explanation of the application of the SDM-CAN 
interface to networks complying to the J1939 standard. 
NOTE 
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