n
——Indicates the number of bits of meaningless data in the message data [from (8-n) Bit to the 7th Bit
data is meaningless] (n is valid when e=1 and s=1, otherwise n is 0)
e
——
Normal transmission when e=0, accelerated transmission when e=1
;
s
——Indicates whether the data length is specified, 0 means the data
length is not specified, 1 means the data length is specified
e=0
,
s=0
——Keep by
CiA
;
e=0
,
s=1
——Data Bit is the Bit counter, byte4 is LSB,
byte7 is MSB
e=1——Data Bit is the data to be downloaded.
Table 10-10 and 10-11 show the format of sending and receiving SDO message when reading
parameters.
Table 10-10 Send SDO message when reading parameters
Table
10-11
receive SDO message when reading parameters
Note :
When the SDO message is sent, the command word is 0x40;
If the received data is 1 bit, the received command word is 0x4F; if the received data is 2 bits, the received command
word is 0x4B; if the received data is 4 bits, the received command word is 0x43; if there is an error in the received
data , the received command word is 0x80.
Table 10-12 and 10-13 show the format of sending and receiving SDO message when modifying
parameters.
Table
10-12 Send SDO message when edit parameters
Table 10-13
Receive SDO message when edit parameters
Note :
If the SDO message is sent successfully, the received command word is 0x60; if the
SDO message fails to be sent, the received command word is 0x80.
If the data to be sent is 1 Bit, the command word to send is 0x2F;
If the data to be sent is 2 bits, the command word to send is 0x2B;
If the data to be sent is 4 bits, the sending command word is 0x23.
When the SDO message fails to be sent, you can troubleshoot the problem