812
Chapter 18
AFCAN Controller
User’s Manual U16580EE3V1UD00
If the LIPT pointer is incremented and matches the value of the RGPT pointer minus 1, the ROVF bit
(receive history list overflow) of the CnRGPT register is set to 1. This indicates that the RHL is full of
numbers of message buffers that have not been read. When further message reception and storing
occur, the last recorded message buffer number is overwritten by the number of the message buffer that
received and stored the newly received message. In this case, after the ROVF bit has been set (1), the
recorded message buffer numbers in the RHL do not completely reflect the chronological order. How-
ever messages itself are not lost and can be located by CPU search in message buffer memory with the
help of the DN-bit.
Caution:
If the history list is in the overflow condition (ROVF is set), reading the history list
contents is still possible, until the history list is empty (indicated by RHPM flag set).
Nevertheless, the history list remains in the overflow condition, until ROVF is cleared
by software. If ROVF is not cleared, the RHPM flag will also not be updated (cleared)
upon a message storage of newly received frame. This may lead to the situation, that
RHPM indicates an empty history list, although a reception has taken place, while the
history list is in the overflow state (ROVF and RHPM are set).
As long as the RHL contains 23 or less entries the sequence of occurrence is maintained. If more
receptions occur without reading the RHL by the host processor, complete sequence of receptions can
not be recovered.
Figure 18-29:
Receive history list
2
3
1
2
3
4
5
6
7
Receive hi
s
tory li
s
t (RHL)
2
3
1
2
3
4
5
6
7
Receive hi
s
tory li
s
t(RHL)
L
as
t in-me
ssa
ge
pointer(LIPT)
2
3
0
1
2
3
4
5
6
7
2
3
1
2
3
4
5
6
7
0
:
:
:
:
:
:
:
:
:
22
0
0
22
22
22
Me
ssa
ge
bu
ffer 7
Me
ssa
ge
bu
ffer 2
Me
ssa
ge
bu
ffer 9
Me
ssa
ge
bu
ffer 6
Me
ssa
ge
bu
ffer
8
Me
ssa
ge
bu
ffer 4
Me
ssa
ge
bu
ffer
3
Receive hi
s
tory
li
s
t get pointer
(RGPT)
Receive hi
s
tory li
s
t(RHL)
Me
ssa
ge
bu
ffer 1
Me
ssa
ge
bu
ffer 5
Me
ssa
ge
bu
ffer
8
Me
ssa
ge
bu
ffer 4
Me
ssa
ge
bu
ffer
3
Me
ssa
ge
bu
ffer 10
Me
ssa
ge
bu
ffer 6
Me
ssa
ge
bu
ffer 11
Me
ssa
ge
bu
ffer 9
Receive hi
s
tory
li
s
t get pointer
(RGPT)
L
as
t in-me
ssa
ge
pointer(LIPT)
ROVF = 1
LIPT i
s
b
locked.
Receive hi
s
tory
li
s
t get pointer
(RGPT)
Receive hi
s
tory
li
s
t get pointer
(RGPT)
L
as
t in-me
ssa
ge
pointer(LIPT)
Me
ssa
ge
bu
ffer 1
Me
ssa
ge
bu
ffer 9
Me
ssa
ge
bu
ffer 10
Me
ssa
ge
bu
ffer 5
Me
ssa
ge
bu
ffer
3
Me
ssa
ge
bu
ffer 4
Me
ssa
ge
bu
ffer
8
Me
ssa
ge
bu
ffer 11
Receive hi
s
tory li
s
t (RHL)
L
as
t in-me
ssa
ge
pointer(LIPT)
ROVF = 1
LIPT i
s
b
locked.
Me
ssa
ge
bu
ffer 15
Event:
- me
ssa
ge
bu
ffer 6, 9, 2
a
nd 7
a
re re
a
d
b
y ho
s
t proce
ss
or.
- Newly received me
ssa
ge
s
a
re
s
tored in me
ssa
ge
bu
ffer
3
, 4
a
nd
8
.
Event:
- reception in me
ssa
ge
bu
ffer 1
3
, 14
a
nd 15 occ
u
r
s
.
- Overflow
s
it
ua
tion occ
u
r
s
.
Event:
- 20 other me
ssa
ge
s
a
re received.
Me
ssa
ge
bu
ffer 6 c
a
rrie
s
l
as
t received me
ssa
ge.
- Upon reception in me
ssa
ge
bu
ffer 6, RHL i
s
f
u
ll.
- ROVF i
s
s
et.
ROVF = 1 define
s
th
a
t LIPT e
qua
l
s
RGPT - 1 while me
ssa
ge
bu
ffer n
u
m
b
er
s
tored to element indic
a
ted
b
y LIPT - 1.
Summary of Contents for V850E/PH2
Page 6: ...6 Preface User s Manual U16580EE3V1UD00...
Page 16: ...16 User s Manual U16580EE3V1UD00...
Page 28: ...28 User s Manual U16580EE3V1UD00...
Page 32: ...32 User s Manual U16580EE3V1UD00...
Page 84: ...84 Chapter 2 Pin Functions User s Manual U16580EE3V1UD00 MEMO...
Page 144: ...144 Chapter 3 CPU Functions User s Manual U16580EE3V1UD00 MEMO...
Page 192: ...192 Chapter 5 Memory Access Control Function PD70F3187 only User s Manual U16580EE3V1UD00 MEMO...
Page 312: ...312 Chapter 9 16 Bit Timer Event Counter P User s Manual U16580EE3V1UD00 MEMO...
Page 534: ...534 Chapter 11 16 bit Timer Event Counter T User s Manual U16580EE3V1UD00...
Page 969: ...969 Chapter 20 Port Functions User s Manual U16580EE3V1UD00 MEMO...
Page 970: ...970 Chapter 20 Port Functions User s Manual U16580EE3V1UD00...
Page 976: ...976 Chapter 22 Internal RAM Parity Check Function User s Manual U16580EE3V1UD00 MEMO...
Page 984: ...984 Chapter 23 On Chip Debug Function OCD User s Manual U16580EE3V1UD00 MEMO...
Page 1006: ...1006 Chapter 24 Flash Memory User s Manual U16580EE3V1UD00 MEMO...
Page 1036: ...1036 Chapter 27 Recommended Soldering Conditions User s Manual U16580EE3V1UD00 MEMO...
Page 1046: ...1046 Appendix A Index User s Manual U16580EE3V1UD00 MEMO...
Page 1052: ...1052 User s Manual U16580EE3V1UD00...
Page 1053: ......