Rev. 1.0, 09/02, page 377 of 568
15.3.16 Unread Message Status Register (UMSR)
UMSR is a 16-bit register containing status flags that indicate, for individual mailboxes (buffers),
that a received message has been overwritten by a new receive message before being read. When
overwritten by a new message, data in the unread receive message is lost.
Bit
Bit Name
Initial Value
R/W
Description
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
UMSR7
UMSR6
UMSR5
UMSR4
UMSR3
UMSR2
UMSR1
UMSR0
UMSR15
UMSR14
UMSR13
UMSR12
UMSR11
UMSR10
UMSR9
UMSR8
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
R/(W)
*
R/(W)
*
R/(W)
*
R/(W)
*
R/(W)
*
R/(W)
*
R/(W)
*
R/(W)
*
R/(W)
*
R/(W)
*
R/(W)
*
R/(W)
*
R/(W)
*
R/(W)
*
R/(W)
*
R/(W)
*
[Setting condition]
•
When a new message is received before RXPR
is cleared
[Clearing condition]
•
Writing
1
•
When the received message has been
overwritten by a new message before being
read.
Note:
*
Only 1 can be written to clear the flag.
Summary of Contents for H8S/2627
Page 22: ...Rev 1 0 09 02 page xx of xxxvi Index 565 ...
Page 30: ...Rev 1 0 09 02 page xxviii of xxxiv ...
Page 36: ...Rev 1 0 09 02 page xxxiv of xxxiv Table 23 9 Flash Memory Characteristics 561 ...
Page 82: ...Rev 1 0 09 02 page 46 of 568 ...
Page 88: ...Rev 1 0 09 02 page 52 of 568 ...
Page 98: ...Rev 1 0 09 02 page 62 of 568 ...
Page 156: ...Rev 1 0 09 02 page 120 of 568 ...
Page 390: ...Rev 1 0 09 02 page 354 of 568 ...
Page 480: ...Rev 1 0 09 02 page 444 of 568 ...
Page 512: ...Rev 1 0 09 02 page 476 of 568 ...
Page 528: ...Rev 1 0 09 02 page 492 of 568 ...
Page 580: ...Rev 1 0 09 02 page 544 of 568 ...