Node Guarding; Transfer Synchronization - Satec EM133 Reference Manual

Table 2-9 TPDO-EM133 Sent Data Bytes Mapping
Communication object
TPDO1
TPDO2
TPDO3
TPDO4
Example:
The device response to the example request in "Master Request Block" above is as
following:
COB ID DLC
1 F E 8
2 F E 8
3 F E 8
4 F E 8
The first four bytes of the response (TPDO1 Bytes 1-4) just repeat the master request
"010E0C00" and the following bytes contain requested data, each point four bytes (32
bits) long, high order bytes first:
TPDO1 Bytes 5-8 (V1): "0000048A" in hex, or 1162 decimal. Asuming the meter PT ratio
is set 1.0, the voltage unit is 0.1V and the actual V1 reading is 116.2V.
TPDO2 Bytes 1-4 (V2): "0000048A" in hex, or 1162 decimal, so the actual V2 reading is
116.2V.
TPDO2 Bytes 5-8 (V3): "0000048C" in hex, or 1164 decimal, so the actual V3 reading is
116.4V
The other requested parameters are place in the EM133 transmited data as follows:
TPDO3 Bytes 1-4: I1
TPDO3 Bytes 5-8: I2
TPDO4 Bytes 1-4: I3
TPDO4 Bytes 5-8: kW L1
The values of these parameters are calculated as showed for the phase voltages.

Node Guarding

The EM133 CANopen module is not configured to use Heartbeat Node Guarding by
default. Hense the CANopen master should either configure the node to use the Heartbeat
protocol or use the "Guard Time" node guarding protocol for checking whether a node is
"alive" or not.

Transfer Synchronization

When a master request is responded, the response synchronization bit is synchronized
with the master synchronization bit. Since CANopen master transfers are handled in a
cyclic fashion (as mentioned in the "Overview" section above), this bit allows the master
to control a sequence of pairs "request-response" by simply toggling the synchronization
bit in the successive master requests.
In write requests, repeated writes will not be handled if the synchronization bit does not
change. If a number of successive writes is required, either toggle the synchronization bit,
or send a "Read" or "Clear" command after each write to clear your previous write
command.
10
COB ID [hex]
0x180 + Node ID (e.g. 0x01FE for Node ID = 126)
0x280 + Node ID (e.g. 0x02FE for Node ID = 126)
0x380 + Node ID (e.g. 0x03FE for Node ID = 126)
0x480 + Node ID (e.g. 0x04FE for Node ID = 126)
Byte 1 Byte 2 Byte 3
0 1 0 E 0 C
0 0 0 0 0 4
X X X X X X
X X X X X X
Byte 4 Byte 5 Byte 6
0 0 0 0 0 0
8 A 0 0 0 0
X X X X X X
X X X X X X
EM133 Sent Bytes
Byte #0 ÷ Byte #7
Byte #8 ÷ Byte #15
Byte #16 ÷ Byte #23
Byte #24 ÷ Byte #31
Byte 7 Byte 8
0 4 8 A
0 4 8 C
X X X X
X X X X