AT32F435/437
Series Reference Manual
2022.11.11
Page 542
Rev 2.03
Bit 15: 8
ATWT
0xFC
rw
Attribute memory wait time
Specifies the attribute memory wait time when the
XMC_NWE and XMC_NOE is low.
00000000: 0 HCLK cycle is inserted
00000001: 1 additional HCLK cycle is inserted
……
11111111: 255 additional HCLK cycles are inserted
Bit 7: 0
ATST
0xFC
rw
Attribute memory setup time
This field defines the address setup time when access to
NAND Flash in an attribute space.
00000000: 0 HCLK cycle is inserted
00000001: 1 additional HCLK cycle is inserted
……
11111111: 255 additional HCLK cycles are inserted
24.7.3.5 IO space timing register 4 (XMC_ BK4TMGIO)
Accessed by words.
Bit
Register
Reset value
Type
Description
Bit 31: 24 IODHIZT
0xFC
rw
I/O space databus High resistance time
This field defines the databus high resistance duration
when write access to NAND Flash is started in an IO
space.
00000000: 0 HCLK cycle is inserted
00000001: 1 additional HCLK cycle is inserted
……
11111111: 255 additional HCLK cycles are inserted
Bit 23: 16 IOHT
0xFC
rw
I/O space hold time
This field defines the databus hold time when access to
NAND Flash in an IO space.
00000000: Reserved
00000001: 1 HCLK cycle is inserted
……
11111111: 255 HCLK cycles are inserted
Bit 15: 8
ATWT
0xFC
rw
Attribute memory wait time
Specifies the IO wait time when the XMC_NWE and
XMC_NOE is low.
00000000: 0 HCLK cycle is inserted
00000001: 1 additional HCLK cycle is inserted
……
11111111: 255 additional HCLK cycles are inserted
Bit 7: 0
IOST
0xFC
rw
IO space setup time
This field defines the address setup time when access to
NAND Flash in an IO space.
00000000: 0 HCLK cycle is inserted
00000001: 1 additional HCLK cycle is inserted
……
11111111: 255 additional HCLK cycles are inserted
24.7.4 SDRAM controller registers
24.7.4.1 SDRAM control register 1, 2 (SDRAM_CTRL1,SDRAM_CTRL2)
This register contains the control parameters for each SDRAM memory bank.
Bit
Register
Reset value
Type
Description
Bit 31: 15 Reserved
0x00000
resd
Kept at its default value.
Bit 14: 13 RD
0x0
rw
Read delay
This field defines the delay (in HCLK clock cycles) for
reading data after CAS latency.
00: No HCLK clock cycle delay
01: 1 HCLK clock cycle delay
10: 2 HCLK clock cycle delay
11: Reserved, do not use.
Note: The corresponding bits in the CTRL2 register are
“don’t care bit”
Bit 12
BSTR
0x0
rw
Burst read