Receive/Transmit Process Data; Bfm #20] Data Exchange Control - Mitsubishi Electric MELSEC-F FX3U-CAN User Manual

FX -CAN User's Manual
3U
6.3

Receive/Transmit Process Data

BFM #10000 to #10319 and #11000 to #11319 locations in the FX
communication to the CAN bus. The mapping for where each data is sent/received is explained in the
following chapter.
Note
®
In the CANopen
to #11003 (TPDO1/RPDO1) are usable. BFM #4 to #399, BFM #10004 to #10319 and BFM #11004 to
#11319 are not accessible.
6.4

[BFM #20] Data Exchange Control

To ensure that the FX
set in BFM #20 the corresponding Bit to ON before reading data (FROM) and after writing data (TO). The
data exchange control signal ensures, by internal buffer exchange, that TO data from the PLC will be
transmitted by PDO.
PDO transmit data will only be sent to the CAN bus if the module is in NMT state Operational and after setting
the corresponding bits in BFM #20 to ON. As long as the reading of the previous data is not finished and a
new exchange command to BFM #20 has not been sent, FROM data will not be overwritten by further PDO.
If the module is in NMT state Operational, PDO data received from other nodes can be read by the FX
FX /FX /FX
3GC 3U 3UC
to the module and sent to the network by using a TO instruction.
The exchange data bit's will be reset automatically when the data exchange between BFM and Object
Dictionary/Data exchange buffer is finished.
Note
• BFM #20 bit 0 will be reset automatically.
• During an active data exchange (BFM #20 bit 0 is ON), new write access to this BFM will be ignored.
Bit
Data exchange status
OFF: Data exchange between BFM's and Data Exchange
Buffer completed
ON: Module exchanges data between BFM's and Data
exchange buffer
Bit 0
Note: This bit has the same function as Bit 8
Bit 1 to 7 Reserved
Only in CANopen
Data exchange status (only OD data)
OFF: Data exchange between BFM's and Data Exchange
Buffer completed
ON: Module exchanges data between BFM's and Data
exchange buffer
Note: This bit has the same function as Bit 0
Bit 8
→ When using the 11 bit CAN-ID Layer 2 mode or 29 bit CAN-ID Layer 2 mode,
417 Mode (BFM #21 = K417), only BFM #0 to #3, BFM #10000 to #10003 and BFM #11000
-CAN module can handle the CANopen
3U
/FX5U/FX5UC PLC by using a FROM instruction, and transmit PDO data can be written
FROM (Read Access)
®
modes:
6.3 Receive/Transmit Process Data
-CAN module are used for data
3U
®
→ When using CANopen
®
→ When using CANopen
®
data in a consistent way, it is necessary to
Description
TO (Write Access)
Data exchange mode Control
OFF: No data exchange between BFMs and CANopen
object dictionary / Layer 2 message buffer
ON: Activate data
®
CANopen object dictionary / Layer 2 message buffer
Notes:
• This bit merges the function of Bit 8, 9 and 12.
• If the bit is set and the Module is not in CANopen
Pre-Operational or Stopped, the PDO data will be
exchanged after going into Operational state.
®
Only in CANopen modes:
Data exchange mode setting (only OD data)
OFF: No data exchange between BFM and CANopen
object dictionary
ON: Activate data exchange between BFM and CANopen
object dictionary
Notes:
• The RPDO data of the Virtual Input mapping BFMs are
not included in this data exchange. It can be handled
separately by Bit 9.
• The data will be also exchanged by setting Bit 0
• If the bit is set and the Module is not in CANopen
Operational, the PDO data will be exchanged after going
into Operational state.
6 Allocation of Buffer Memories
405 mode, refer to Chapter 7
417 mode, refer to Chapter 8
refer to Chapter 9
exchange between BFMs
®
state
®
state
111
1
2
3
4
5
/
3G
6
7
®
and
8
9
®
®
10