schmersal Praxi 100, Manual

Page: 41 / 52

41
6.5.2 Example 2 - Read Process Data
Command Master - Slave:
Answer Slave - Master:
Reply Frame:
Message Frame:
Read the Process Data 42103…42104 with command 4 (Read Input Registers).
Table 41.
Table 40.
Table 39.
Table 42.
The reply to the Read Input Registers message contains the values of the read registers.
Address 01 hex Slave address 1 hex (= 1)
Function 04 hex Function 4 hex (= 4)
Data
Starting address HI 08 hex
Starting address 0836 hex (= 2102)
Starting address LO 36 hex
No. of registers HI 00 hex
Number of registers 0002 hex (= 2)
No. of registers LO 02 hex
Error Check
CRC HI 93 hex
CRC field 93A5 hex (= 37797)
CRC LO A5 hex
Address 01 hex Slave address 1 hex (= 1)
Function 04 hex Function 4 hex (= 4)
Data
Byte Count 04 hex Byte Count 4 hex (=4)
Data HI 13 hex
Speed reference = 1388 hex (=5000 => 50.00%)
Data LO 88 hex
Data HI 09 hex
Output Frequency = 09C4 hex (=2500 =>25.00Hz)
Data LO C4 hex
Error Check
CRC HI 78 hex
CRC field 78E9 hex (=30953)
CRC LO E9 hex
01 10 07 D0 00 03 80 85
01 04 08 36 00 02 93 A5