ISD94100 Series Technical Reference Manual
Sep 9, 2019
Page
196
of 928
Rev1.09
IS
D
9
410
0
S
ER
IE
S
T
E
C
HN
ICA
L
RE
F
E
RE
NCE
M
AN
U
AL
CBS[1:0]
Running mode
Load System Vector table from
Support Vector Re-Mapping
00
LDROM with IAP
0x0010_0000 - 0x0010_01FF
Yes
01
LDROM without IAP
0x0010_0000 - 0x0010_01FF
No
10
APROM with IAP
0x0000_0000 - 0x0010_01FF
Yes
11
APROM without IAP
0x0000_0000 - 0x0010_01FF
No
Table 6.4.4-2 Boot Configuration
6.4.4.2.1 Boot from LDROM with IAP support
By writing 0b00 into CBS[1:0] bits in CONFIG0, the ISD94100 device will map the system vector
table into LRDOM space, which has physical memory address from 0x0100_0000 - 0x0100_01FF.
In other words, MCU will no longer load the vector value from APROM address 0x0000_0000 to
0x0000_01FF, it loads the vector values from LDROM space 0x0010_0100 to 0x0010_01FF.
In this mode, the MCU boots from LDROM, and has the access to all memory space, including
512KB APROM and 4KB LDROM. The device can read, erase and write other parts of the memory
so that the IAP function can be implemented.
This mode supports dynamic remapping so that APROM, LDROM or SRAM address can be
remapped into system vector table. Remapping can be achieved by first writing the target remap-
to address to FMC_ISPADDR register and then triggering ISP procedure with the “Vector Remap”
command (0x2E). The targeted remapping address needs to be in alignment with 512 bytes. In
VECMAP (FMC_ISPSTS[23:9]), shows the finial system vector mapping address.
0x0000_0000
0x0010_0000
0x0010_0FFF
ApplicationROM
(APROM)
Loader ROM
(LDROM 4KB)
Reserved
Reserved
DFBA
0x0000_01FF
0x0000_0200
System Vector Table
512
KB
Data Flash
0x0007_FFFF
0x0010_01FF
0x0010_0200
4
KB
Mapping to
Figure 6.4-4 Boot from LDROM with IAP support