System Integration Unit (SIU)
MPC5510 Microcontroller Family Reference Manual, Rev. 1
Freescale Semiconductor
6-17
Preliminary
6.3.2.7
Overrun Status Register (SIU_OSR)
The SIU_OSR contains flag bits that record an overrun. These flag bits are cleared by writing 1 to the bits
(w1c); writing 0 has no effect.
Offset:
SI 000x1C
Access: User read/write
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
R
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
R
0
0
0
0
0
0
0
0
0
0
0
DIRS4 DIRS3 DIRS2 DIRS1
0
W
Reset
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
Do not write a 1 to bit 31 as it will block interrupt function of IRQ0.
Figure 6-7. DMA/Interrupt Request Select Register (SIU_DIRSR)
Table 6-9. SIU_DIRER Field Descriptions
Field
Description
bits 0–26 Reserved.
DIRSn
DMA/Interrupt Request Select n. Selects between a DMA or interrupt request when an edge triggered event occurs
on the corresponding IRQn pin.
0 Interrupt request selected.
1 DMA request selected.
bit 31
Reserved.
Note: Reserved bit 31 is writeable, but setting this bit will block the interrupt function of IRQ0. Thus, this bit should
not be written to a one.
Offset
:
SI 0x0020
Access: User read/write
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
R
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
R OVF15 OVF14 OVF13 OVF12 OVF11 OVF10 OVF9 OVF8 OVF7 OVF6 OVF5 OVF4 OVF3 OVF2 OVF1 OVF0
W
w1c
w1c
w1c
w1c
w1c
w1c
w1c
w1c
w1c
w1c
w1c
w1c
w1c
w1c
w1c
w1c
Reset
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Figure 6-8. Overrun Status Register (SIU_OSR)