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M0A21/M0A23 Series
May 06, 2022
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220
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Rev 1.02
M0
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ANUAL
LDROM with IAP
LDROM with IAP
CBS[1:0]
00
Controlled by CONFIG0
Boot Source
01
10
11
LDROM without IAP
LDROM without IAP
APROM with IAP
APROM with IAP
APROM without IAP
APROM without IAP
Figure 6.4-8 Boot Source Selection
CBS[1:0]
Boot Selection/System Memory Map
Vector Mapping Supporting
00
LDROM with IAP
Yes
01
LDROM without IAP
No
10
APROM with IAP
Yes
11
APROM without IAP
No
Table 6.4-1 Vector Mapping Support
In-Application-Programming (IAP)
The M0A21/M0A23 provides In-Application-Programming (IAP) function for user to switch the code
executing between APROM and LDROM. User can enable the IAP function by booting chip and setting
the chip boot selection bits in CBS (CONFIG0[7:6]) as 10 or 00.
When chip boots with IAP function enabled, any executable code (align to 512 bytes) is allowed to map
to the system memory vector(0x0000_0000~0x0000_01FF) any time. User can change the remap
address to FMC_ISPADDR and then trigger ISP procedure with the “Vector Page Remap” command.
In-System-Programming (ISP)
The M0A21/M0A23 supports In-System-Programming (ISP) function allowing the embedded Flash
memory to be reprogrammed under software control. ISP is performed without removing the
microcontroller from the system through the firmware and on-chip connectivity interface, such as UART,
I
2
C, and SPI.
The M0A21/M0A23 ISP provides the following functions for embedded Flash memory.
Supports Flash page erase function
Supports Flash data program function
Supports Flash data read function
Supports company ID read function
Supports unique ID read function
Supports memory checksum calculation function