Users Guide: DS80C390 Supplement Manual
High-Speed Microcontroller User’s Guide: DS80C390 Supplement 
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B REGISTER (B) 
 7 6 5 4 3 2 1 0 
SFR F0h B.7 B.6 B.5 B.4 B.3 B.2 B.1 B.0 
  RW-0 RW-0 RW-0 RW-0 RW-0 RW-0 RW-0 RW-0 
R = Unrestricted Read, W = Unrestricted Write, -n = Value after Reset 
B.7-0 
Bits 7-0 
B Register. This register serves as a second accumulator for certain arithmetic 
operations. It is functionally identical to the B register found in the 80C32. 
CAN 1 MESSAGE CENTER 6 CONTROL REGISTER (C1M6C) 
  7 6 5 4 3 2 1 0 
SFR F3h  MSRDY  ETI  ERI  INTRQ  EXTRQ  MTRQ  ROW/TIH DTUP 
  RW-0 RW-0 RW-0 RW-0  RC-0  R*-0  R*-0  R*-0 
R = Unrestricted Read, C = Clear Only, * = See description below, -n = Value after Reset 
C1M6C 
Bits 7-0 
Operation of the bits in this register are identical to those found in the CAN 1 
Message One Control Register (C1M1C;ABh). Please consult the description 
of that register for more information. 
CAN 1 MESSAGE CENTER 7 CONTROL REGISTER (C1M7C) 
  7 6 5 4 3 2 1 0 
SFR F4h  MSRDY  ETI  ERI  INTRQ  EXTRQ  MTRQ  ROW/TIH DTUP 
  RW-0 RW-0 RW-0 RW-0  RC-0  R*-0  R*-0  R*-0 
R = Unrestricted Read, C = Clear Only, * = See description below, -n = Value after Reset 
C1M7C 
Bits 7-0 
Operation of the bits in this register are identical to those found in the CAN 1 
Message One Control Register (C1M1C;ABh). Please consult the description 
of that register for more information. 
CAN 1 MESSAGE CENTER 8 CONTROL REGISTER (C1M8C) 
  7 6 5 4 3 2 1 0 
SFR F5h  MSRDY  ETI  ERI  INTRQ  EXTRQ  MTRQ  ROW/TIH DTUP 
  RW-0 RW-0 RW-0 RW-0  RC-0  R*-0  R*-0  R*-0 
R = Unrestricted Read, C = Clear Only, * = See description below, -n = Value after Reset 
C1M8C 
Bits 7-0 
Operation of the bits in this register are identical to those found in the CAN 1 
Message One Control Register (C1M1C;ABh). Please consult the description 
of that register for more information. 










