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AT32F435/437
Series Reference Manual
2022.11.11
Page 516
Rev 2.03
Table 24-20
Mode B— SRAM/NOR Flash chip select timing register
Bit
Description
Configuration
Bit 31: 30
Reserved
0x0
Bit 29: 28
ASYNCM: Asynchronous mode
0x1 (Mode B)
Bit 27: 24
DTLAT: Data latency
0x0
Bit 23: 20
CLKPSC: Clock prescale
0x0
Bit 19: 16
BUSLAT: Bus latency
Indicates the time the XMC_NE[x] from the rising edge to the
falling edge. Configure according to needs and memory
specifications
Bit 15: 8
DTST: Data setup time
Refer to
Configure according to needs and
memory specifications.
Bit 7: 4
ADDRHT: Address-hold time
0x0
Bit 3: 0
ADDRST: Address setup time
Refer to
Configure according to needs and
memory specifications.
Table 24-21
Mode B— SRAM/NOR Flash write timing register
Bit
Description
Configuration
Bit 31: 30
Reserved
0x0
Bit 29: 28
ASYNCM: Asynchronous mode
0x1 (Mode B)
Bit 27: 20
Reserved
0x0
Bit 19: 16
BUSLAT: Bus latency
Indicates the time the XMC_NE[x] from the rising edge to the
falling edge. Configure according to needs and memory
specifications
Bit 15: 8
DTST: Data setup time
. Configure according to needs and
memory specifications.
Bit 7: 4
ADDRHT: Address-hold time
0x0
Bit 3: 0
ADDRST: Address setup time
. Configure according to needs and
memory specifications.
Figure 24-9
NOR/PSRAM mode B 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
XMC_NADV
Don
t care
Address signals
Data signals
Chip select
signal
XMC_LB
XMC_UB
XMC_A[25
:
0]