![ARTERY AT32F435 Series Скачать руководство пользователя страница 511](http://html1.mh-extra.com/html/artery/at32f435-series/at32f435-series_reference-manual_2977592511.webp)
AT32F435/437
Series Reference Manual
2022.11.11
Page 511
Rev 2.03
Figure 24-3 NOR/PSRAM m ode 1 read access
XMC_NE[x]
XMC_NOE
XMC_NWE
XMC_D[15
:
0]
Data from external
memory
1
HCLK
DTST+1
HCLK
High
2
HCLK
XMC capture
data
Memory address
High-Z
Don
t care
Data signals
Chip select
signal
XMC_A[25
:
0]
Address signals
XMC_LB
XMC_UB
Figure 24-4 NOR/PSRAM m ode 1 write access
XMC_A[25
:
0]
XMC_NE[x]
XMC_NOE
XMC_NWE
XMC_D[15
:
0]
1
HCLK
Data from XMC
1
HCLK
DTST+1
HCLK
High
High-Z
Memory address
Don
t care
Address signals
Data signals
Chip select
signal
XMC_LB
XMC_UB
Mode 2
As configured in Table 24-14 and Table 24-15,
the XMC uses mode 2 to access the external memory.
The timing of read operation is shown in Figure 24-5
The timing of write operation is shown in Figure
Table 24-14
Mode 2
— SRAM/NOR Flash chip select control register
Bit
Description
Configuration
Bit 31: 20
Reserved
0x0
Bit 19
MWMC: Memory write mode control
0x0
Bit 18: 16
CRPGS
:
CRAM page size
0x0
Bit 15
NWASEN: NWAIT in asynchronous
transfer enable
Configure according to memory specifications.