ElmoMC CANopen DS 301 Implementation Guide - Manual (Page 44)

If an interpreter command cannot be serviced for any reason, bit 6 in byte 3 of TPDO2 is
set on, and byte 4 of the response contains the Elmo error code (refer to the EC command
section of the SimplIQ Command Reference Manual).
9.1 Binary Interpreter Commands and Results
The sequences in this section illustrate the binary interpreter options for setting, querying
and executing commands.
9.1.1 Set and Query Commands
The host (client) sends commands (RPDO2) for setting variables in eight bytes (DLC=8).
The drive (server) transmits the reply (TPDO2) as an asynchronous event of the received
object.
9.1.1.1 RPDO2 Structure
RPDO2 is used to set values for the drive and query (get) values from it. The structure of
the command is as follows:
ƒ
Bytes 0 to 3 are the header, which includes the command, command index (when
needed) and data type (float or integer).
ƒ Bytes 4 to 7 are the data, which is always four bytes. The format can be integer or
float. The bytes are interpreted in little endian format (see
Appendix ).
The following table describes the format in which the host sends commands to the drive:
Byte 0 1 2 3 4 - 7
Bits 0…7 0…7 0…7 0…5 6 7
Description First
command
character
Second
command
character Index for array
parameter. 0 for
scalar command See
note 0: Integer
1: float Data in little
endian
format
Note: Bytes 0 and 1, which represent the command character in ASCII, must be
uppercase.
Byte 3, bit 6:
When this bit is set to 1, the drive treats the command as a “query” and not as a “setting.”
In this case, the rest of the data bytes are discarded and the drive replies to the command
according to 4 bytes DLC. For compatibility reasons, bytes 4 to 7 should be 0.
CANopen DS 301 Implementation Guide Binary Interpreter Commands
MAN-CAN301IG (Ver. 2.1)
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