Datasheet

Section 15 Controller Area Network for Tiny (TinyCAN)
Rev. 4.00 Mar. 15, 2006 Page 311 of 556
REJ09B0026-0400
15.3.13 Unread Message Status Register (UMSR)
UMSR is a status flag that indicates that an unread message in each Mailbox has been overwritten
by a new receive message or a new receive message has been discarded.
Bit Bit Name
Initial
Value R/W Description
7 to 4 — All 0 — Reserved
These bits are always read as 0.
3
2
1
0
MB3
MB2
MB1
MB0
0
0
0
0
R/(W)*
R/(W)*
R/(W)*
R/(W)*
Status flags indicating that a new receive message has
overwritten/overrun an unread message.
[Setting condition]
When a new message is received before the
corresponding bit in RXPR or RFPR is cleared to 0
[Clearing condition]
When 1 is written to these bits
Note: * Only 1 can be written to clear the flag.