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AT32F435/437
Series Reference Manual
2022.11.11
Page 543
Rev 2.03
When this bit is set, it indicates that single AHB requests
(single or burst) are processed as bursts. Several data will
be prefetched and stored into the FIFO.
0: Single read requests are not processed as bursts
1: ingle read requests are always processed as bursts
Note: The corresponding bits in the CTRL2 register are
“don’t care bit”
Bit 11: 10 CLKDIV
0x0
rw
Clock division configuration
SDRAM clock configuration.
00: SDCLK clock disabled
01: HCLK/4
10: HCLK/2
11: HCLK/3
Note: The corresponding bits in the CTRL2 register are
“don’t care bit”
Bit 9
WRP
0x0
rw
Write protection
This bit is set to enable the SDRAM write protection.
0: Write access allowed
1: Write access forbidden
Bit 8: 7
CAS
0x0
rw
CAS latency
This field is used to select CAS latency.
00: Reserved, do not use.
01: 1 cycle
10: 2 cycles
11: 3 cycles
Bit 6
INBK
0x0
rw
Internal banks
This bit is used to define the number of internal banks.
0: 2 internal BANKs
1: 4 internal BANKs
Bit 5: 4
DB
0x0
rw
SDRAM data bus
This field enables 8-bit or 16-bit data bus width.
00: 8 bits
01: 16 bits
10: Reserved, do not use.
11: Reserved, do not use.
Bit 3: 2
RA
0x0
rw
Row address
This field defines the number of a row address, including
11 bits, 12 bits and 13 bits.
00: 11 bits
01: 12 bits
10: 13 bits
11: Reserved, do not use.
Bit 1: 0
CA
0x0
rw
Column address
This field defines the number of a column address,
including 8 bits, 9 bits, 10 bits and 13 bits.
00: 8 bits
01: 9 bits
10: 10 bits
11: 11 bits
24.7.4.2 SDRAM timing register 1, 2 (SDRAM_TM1,SDRAM_TM2)
This register contains the timing parameters of each SDRAM bank.
Bit
Register
Reset value
Type
Description
Bit 31: 28 Reserved
0x0
resd
Kept at its default value.
Bit 27: 24 TRCD
0xF
rw
Row active to Read/Write delay
This field defines the delay between the activate command
and a read/write command in number of clock cycles.
0000: 1 cycle
0001: 2 cycles
....
1111: 16 cycles
Bit 23:20
TRP
0xF
rw
Precharge to active delay
This field defines the delay between a precharge
command and another command in number of clock