Satec EM133, Reference Manual

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Table 2-1 Read Request Block
Bytes Description Range Type Notes
0,1 Command control See Table 2-3 UINT16
2,3 Start point ID 0x0000-0xFFFF UINT16
Table 2-2 Write Request Block
Bytes Description Range Type Notes
0,1 Command control See Table 2-3 UINT16
2,3 Start point ID 0x0000-0xFFFF UINT16
4-31 Data block INT16/INT
32
32-bit integers occupy two
16-bit words – most
significant first
Table 2-3 Request Control
Byte Bits Description Range Notes
0 0-1 Operation 00=No operation
01=Read
10=Write
11=Clear
“Clear” and “No operation” remove the last
master command sent and clear the CANopen
input buffer. After the device restarts, “Write”
commands are ignor ed until “Clear” or “Read” is
sent first for device synchronization.
2 Data type 0=32-bit integer
1=16-bit integer
32-bit integers occupy two 16-bit words – most
significant first
3 Unused
4 16-bit linear
scaling 0=disabled
1=enabled Only applied to 16-bit analog registers. Will not
affect binary registers and counters.
5-6 Unused
7 Synchronization
bit 0-1 Toggle the bit to synchronize a response
1 0-3 Word count 1-14 Defines the number of words in the data block
4-7 Unused
Note: Bit 0 is a least significant bit (LSB).
The following table describes the mapping between RPDOs and data bytes received by the
EM133:
Table 2-4 RPDO-EM133 Received Data Bytes Mapping
Communication object COB ID [hex] EM133 Received Bytes
RPDO1 0x200 + Node ID (e.g. 0x027E for Node ID = 126) Byte #0 ÷ Byte #7
RPDO2 0x300 + Node ID (e.g. 0x037E for Node ID = 126) Byte #8 ÷ Byte #15
RPDO3 0x400 + Node ID (e.g. 0x047E for Node ID = 126) Byte #16 ÷ Byte #23
RPDO4 0x500 + Node ID (e.g. 0x057E for Node ID = 126) Byte #24 ÷ Byte #31
Example:
In order to read seven data points in a double word format (32 bits), i.e. 14 words,
starting with point 0x0C00 (V1-V3, I1-I3, kW L1, see section 3.1 below), from EM133
with CANopen Node ID = 126, the CANopen master writes a request as follows:
COB ID DLC Byte 1 Byte 2 Byte 3 Byte 4 Byte 5 Byte 6 Byte 7 Byte 8
2 7 E 8 0 1 0 E 0 C 0 0 0 0 0 0 0 0 0 0
The first byte (Byte 1) contains a READ command (0x01), the second byte requests
reading of 14 words (0x0E), and bytes 3 and 4 specify the start point address of 0x0C00.
The CANopen master can request the EM133 to transmit TPDO1÷TPDO4 that contains the
data it needs by sending an empty TPDOs with the RTR flag.