User Manual
Apollo3 Blue Datasheet
DS-A3-0p9p1 Page 138 of 909 2019 Ambiq Micro, Inc.
All rights reserved.
3.8.2.19 SHADOWVALID Register
Register to indicate whether the shadow registers have been successfully loaded from the Flash
Information Space.
OFFSET: 0x000001A4
INSTANCE 0 ADDRESS: 0x400201A4
Register to indicate whether the shadow registers have been successfully loaded from the Flash
Information Space.
3.8.2.20 SCRATCH0 Register
Scratch register that is not reset by any reset
OFFSET: 0x000001B0
0
BOOTLOADER-
LOW
0x1 RW
Determines whether the bootloader code is visible at address 0x00000000
or not. Resets to 1, write 1 to clear.
ADDR0 = 0x1 - Bootloader code at 0x00000000.
Table 167: SHADOWVALID Register
3
1
3
0
2
9
2
8
2
7
2
6
2
5
2
4
2
3
2
2
2
1
2
0
1
9
1
8
1
7
1
6
1
5
1
4
1
3
1
2
1
1
1
0
0
9
0
8
0
7
0
6
0
5
0
4
0
3
0
2
0
1
0
0
RSVD
INFO0_VALID
BLDSLEEP
VALID
Table 168: SHADOWVALID Register Bits
Bit Name Reset RW Description
31:3 RSVD 0x0 RO
RESERVED.
2 INFO0_VALID 0x1 RO
Indicates whether info0 contains valid data
VALID = 0x1 - Flash info0 (customer) space contains valid data.
1 BLDSLEEP 0x1 RO
Indicates whether the bootloader should sleep or deep sleep if no image
loaded.
DEEPSLEEP = 0x1 - Bootloader will go to deep sleep if no flash image
loaded
0VALID 0x1RO
Indicates whether the shadow registers contain valid data from the Flash
Information Space.
VALID = 0x1 - Flash information space contains valid data.
Table 166: BOOTLOADER Register Bits
Bit Name Reset RW Description