DS80C390_00 Datasheet, PDF (122/155 Pages) Dallas Semiconductor – High-Speed Microcontroller User’s Guide Supplement

DS80C390 High-Speed Microcontroller User’s Guide Supplement
CAN Media ID Mask Register 0 (CnMID0)
MOVX
Address¹
7
6
5
4
3
2
1
0
xxxx00h
CAN Media ID Mask Register 1 (CnMID1)
MOVX
Address¹
7
6
5
4
3
2
1
0
xxxx02h
CAN Media ID Mask Registers 1-0. These registers function as the mask when
performing the Media Identification test. This register can only be modified
during a software initialization (SWINT=1). If MDME=0, the Media
Identification test will not be performed and the contents of these registers is
ignored. If MDME=1, the CAN module will perform an additional qualifying test
on Data Bytes 0 and 1 of the incoming message, regardless of the state of the
EX/ ST bit. Data byte 1 will be compared against CAN Media Byte Arbitration
Register 1 utilizing CnMID1 as a mask, and Data byte 0 will be compared against
CAN Media Byte Arbitration Register 0 utilizing CnMID0 as a mask. Any bit in
the CnMID1, CnMID0 masks programmed to 0 will ignore the state of the
corresponding Data Byte bit when performing the test. Any bit in the CnMID1,
CnMID0 masks programmed to 1 will force the state of the corresponding Data
Byte bit and CAN Media Byte Arbitration Registers 1 and 0 to match before
considering the incoming message a match. Programming either Media ID Mask
Register to 00h effectively disables the Media ID test for that byte. As such the
CnMID1, CnMID0 masks act as a don’t care following a system Reset.
CAN Media Arbitration Register 0 (CnMA0)
MOVX
Address¹
7
6
5
4
3
2
1
0
xxxx01h
CAN Media Arbitration Register 1 (CnMA1)
MOVX
Address¹
7
6
5
4
3
2
1
0
xxxx03h
CAN Media Arbitration Register 1-0. These registers function as the arbitration
field when performing the Media Identification test. If MDME=0, the Media
Identification test will not be performed and the contents of these registers is
ignored. If MDME=1, the CAN module will perform an additional qualifying test
on Data Bytes 0 and 1 of the incoming message, as mentioned in the description of
the CAN Media ID Mask Registers. This register can only be modified during a
software initialization (SWINT=1).
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