Operation 4
Table 46. write reg 01 H, data = 10Hex
(SETUP_1 register) AT7908E connected to BUS, remote frame request, standard message, length of data can be any
value.
SETUP_1
Disabled
1
TXRM
0
TXEM
0
TMRMR
0
TXDLC3
0
TXDLC1
0
TXDLC1
0
TXDLC0
0
SETUP_1
Disabled
0
TXRM
0
TXEM
0
TMRMR
1
TXDLC3
0
TXDLC1
0
TXDLC1
0
TXDLC0
0
Transmission request
Operation 5 and 6
Table 47. write reg 03 H, data =0AHex
(SETUP_3 register) Resynchronisation jump length = 2 system clock and transmission request.
SETUP_3
RxClr
0
Reset
0
IntClr
0
AbortTx
0
Txreq
0
RSJ2
0
RSJ1
1
RSJ0
0
SETUP_3
RxClr
0
Reset
0
IntClr
0
AbortTx
0
Txreq
0
RSJ2
0
RSJ1
1
RSJ0
0
At this point, the AT7908E starts to transmit the remote frame request until an acknowl-
edge comes from another CAN node.
In the next figure is reported the standard CAN format on the CAN BUS for the
REMOTE FRAME request.
Figure 13. Remote frame
SOF
ACK
End of
Frame
Control Field
TxOK bit Updated
45
AT7908E
4268D–AERO–11/09
ATMEL [ ATMEL ]
