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XC161 Derivatives
Peripheral Units (Vol. 2 of 2)
TwinCAN Module
User’s Manual
21-31
V2.2, 2004-01
TwinCAN_X1, V2.1
MMC
<d>
= ‘000’:
The operation with a standard message object on the destination side is illustrated in
.
Figure 21-17 Data Frame Reception in Normal Gateway Mode with a Standard
Destination Message Object (MMC
<d>
= ‘000’)
A matching data frame, arrived at the source node, is automatically copied to the
destination node’s message object addressed by CANPTR
<s>
. Bitfield CANPTR
<d>
is
loaded with the destination message object number. Regardless of control bit
SRREN
<d>
, remote frames, received on the destination node, are not transferred to the
source side, but can be directly answered by the destination message object. For this
purpose, control bitfields TXRQ
<d>
and RMTPND
<d>
are set to ‘10’, which immediately
initiates a data frame transmission on the destination CAN bus if CPUUPD
<d>
is reset to
‘01’.
MCA05487
FSIZE = ‘00000’
CANPTR = <d>
MMC = ‘100’
Node = <s>
DIR = ‘0’
DATA
ID
DLC
TXRQ = ‘01’
RMTPND = ‘01’
NEWDAT = ‘10’
INTPND
FSIZE = ‘00000’
CANPTR = <d>
MMC = ‘000’
Node = <d>
DIR = ‘1’
DATA
ID
DLC
TXRQ
RMTPND
NEWDAT = ‘10’
INTPND
Pointer to Destination
Message Object
Data Frame (GDFS<s> = ‘1’)
Data Frame
Copy Data Frame
Gateway
Destination
Gateway
Source
Gateway
Destination CAN Bus
Source CAN Bus
Pointer to
Destination
Message
Object
Copy if DLCC<s> = ‘1’
Copy
Copy if IDC<s> = ‘1’
Reset
Reset
Set
Set if RXIE<s> = ‘1’
Set if RXIE<d> = ‘1’
Set
Unchanged
Set if GDFS<s> = ‘1’