Figure 14-36: Can 1 To 4 Information Registers (C1Last To C4Last) - NEC V850E/CA2 JUPITER Preliminary User's Manual

(4) CAN 1 to 4 information registers (C1LAST to C4LAST)
The CxLAST registers return the number of the last received message and last CAN protocol error
of the corresponding CAN module x (x = 1 to 4 for the derivatives µPD703129(A) and
µPD703129(A1), x = 1 to 2 for the derivative µPD703128(A)).
These registers can be read-only in 8-bit and 16-bit units.

Figure 14-36: CAN 1 to 4 Information Registers (C1LAST to C4LAST)

15 14 13
C1LAST 0 0 0
C2LAST 0 0 0
C3LAST 0 0 0
C4LAST 0 0 0
Bit Position Bit Name
LERR3 to
11 to 8
LERR0
LREC7 to
7 to 0
LREC0
Notes: 1. The register address is calculated according to the following formula:
effective address = PP_BASE + address offset
2. This error code only occurs in single-shot mode (SSHT bit of the CxDEF register = 1).
496
Chapter 14 FCAN Interface Function
12 11 10 9 8
0 LERR3 LERR2 LERR1 LERR0 LREC7 LREC6 LREC5 LREC4 LREC3 LREC2 LREC1 LREC0
0 LERR3 LERR2 LERR1 LERR0 LREC7 LREC6 LREC5 LREC4 LREC3 LREC2 LREC1 LREC0
0 LERR3 LERR2 LERR1 LERR0 LREC7 LREC6 LREC5 LREC4 LREC3 LREC2 LREC1 LREC0
0 LERR3 LERR2 LERR1 LERR0 LREC7 LREC6 LREC5 LREC4 LREC3 LREC2 LREC1 LREC0
Holds the code of the last CAN protocol error.
LERR3 LERR2
0 0
0 0
0 0
0 0
0 1
0 1
0 1
0 1
1 0
Others than above
Remark: The LERR3 to LERR0 bits cannot be cleared. Thus these bits remain
unchanged until the next error occurs.
Holds the message buffer number of the last received message.
LREC7 to LREC0
0 to 31
32 to 255
Preliminary User's Manual U15839EE1V0UM00
7 6 5 4
Function
LERR1 LERR0
0 0 No error (reset state only)
0 1 CAN bus bit error
1 0 CAN bus stuff error
1 1 CAN bus CRC error
0 0 CAN bus form error
0 1 CAN bus acknowledgement error
1 0
CAN bus arbitration lost
1 1 CAN module overrun error
0 0 CAN wake-up from CAN bus
Reserved
Receive Message Buffer Number
Message buffer number of the last received message
Reserved (not possible)
Address
3 2 1 0
Offset
1054H
1094H
10D4H
1114H
Code of Last CAN Protocol Error
Note 2
Initial
Note 1
value
00FFH
00FFH
00FFH
00FFH