Datasheet

531
SAM7X Series [DATASHEET]
6120K–ATARM–11-Feb-14
36.8.17 CAN Message Data Low Register
Name: CAN_MDLx
Access Type: Read-write
• MDL: Message Data Low Value
When MRDY field is set in the CAN_MSRx register, the lower 32 bits of a received message can be read or written by the soft-
ware application. Otherwise, the MDL value is locked by the CAN controller to send/receive a new message.
In Receive with overwrite, the CAN controller may modify MDL value while the software application reads MDH and MDL regis-
ters. To check that MDH and MDL do not belong to different messages, the application has to check the MMI field in the
CAN_MSRx register. In this mode, the software application must re-read CAN_MDH and CAN_MDL, while the MMI bit in the
CAN_MSRx register is set.
Bytes are received/sent on the bus in the following order:
1. CAN_MDL[7:0]
2. CAN_MDL[15:8]
3. CAN_MDL[23:16]
4. CAN_MDL[31:24]
5. CAN_MDH[7:0]
6. CAN_MDH[15:8]
7. CAN_MDH[23:16]
8. CAN_MDH[31:24]
31 30 29 28 27 26 25 24
MDL
23 22 21 20 19 18 17 16
MDL
15 14 13 12 11 10 9 8
MDL
76543210
MDL