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GD32L23x User Manual
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Table 2-4. 32KB flash base address and size for flash memory
Block
Name
Address range
size(bytes)
Main flash block
Page 0
0x0800 0000 - 0x0800 03FF
1KB
Page 1
0x0800 0400 - 0x0800 07FF
1KB
Page 2
0x0800 0800 - 0x0800 0BFF
1KB
Page 31
0x08007C00 - 0x0800 7FFF
1KB
Information block
Boot loader area
0x1FFF D000- 0x1FFF F7FF
10KB
Option bytes block
Option bytes
0x1FFF F800 - 0x1FFF F80F
16B
One-time program block
OTP bytes
0x1FFF_7000~0x1FFF_71FF
512B
Note:
The information block stores the boot loader. This block cannot be programmed or
erased by user.
2.3.2.
Read operations
The flash can be addressed directly as a common memory space. Any instruction fetch and
the data access from the flash are through the IBUS or DBUS from the CPU.
Wait state added:
The WSCNT bits in the FMC_WS register needs to be configured correctly depend on the
AHB clock frequency when reading the flash memory. The relation between WSCNT and
AHB clock frequency is show as the
Table 2-5. The relation between WSCNT and AHB
Table 2-5. The relation between WSCNT and AHB clock frequency when LDO is 1.1V
AHB clock frequency
WSCNT configured
<= 32MHz
0 (0 wait state added)
<= 64MHz
1 (1 wait state added)
Table 2-6. The relation between WSCNT and AHB clock frequency when LDO is 0.9V
AHB clock frequency
WSCNT configured
<= 16MHz
0 (0 wait state added)
<= 36MHz
1 (1 wait state added)
<= 48MHz
2 (2 wait state added)
<= 64MHz
3 (3 wait state added)
If system reset occurs, the AHB clock frequency is 16MHz and the WSCNT is 0.
Note:
1. If want to increase the AHB clock frequency. First, refer to the correspondence table
between WSCNT bit and AHB clock frequency, configure the WSCNT bits according to the
target AHB clock frequency. Then, increase the AHB clock frequency to the target frequency.