GD32F20x User Manual
739
These bits specify the delay from a Self-refresh command to an Activate
command in SDRAM memory clock cycle unit.
0x0: 1 cycle
0x1: 2 cycles
……
0xF: 16 cycles
3:0
LMRD[3:0]
Load Mode Register Delay
These bits specify the delay between a Load Mode Register command and a
Refresh or Active command in SDRAM memory clock cycle unit.
0x0: 1 cycle
0x1: 2 cycles
......
0xF: 16 cycles
SDRAM command register (EXMC_SDCMD)
Address offset: 0x150
Reset value: 0x0000 0000
This register has to be accessed by word(32-bit)
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
Reserved
MRC[12:7]
rw
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
MRC[6:0]
NARF[3:0]
DS0
DS1
CMD[2:0]
rw
rw
rw
rw
rw
Bits
Fields
Descriptions
31:22
Reserved
Must be kept at reset value
21:9
MRC[12:0]
Mode register content
These bits specify the SDRAM Mode Register content which will be programmed
when CMD
= ‘100’.
8:5
NARF[3:0]
Number of successive Auto-refresh
These bits specify how many successive Auto-refresh cycles will be send when
CMD
= ‘011’.
0x0: 1 Auto-refresh cycle
0x1: 2 Auto-refresh cycles
....
0xE: 15 Auto-refresh cycles
0xF: Reserved
4
DS0
Device select 0
Содержание GD32F20 Series
Страница 1: ...GigaDevice Semiconductor Inc GD32F20x ARM Cortex M3 32 bit MCU User Manual Revision 2 2 Oct 2019 ...
Страница 191: ...GD32F20x User Manual 191 Bits Fields Descriptions 31 0 TRNDATA 31 0 32 Bit Random data ...
Страница 290: ...GD32F20x User Manual 290 conversion is ongoing ...
Страница 325: ...GD32F20x User Manual 325 15 0 ALRM 15 0 RTC alarm value low ...
Страница 385: ...GD32F20x User Manual 385 ...
Страница 523: ...GD32F20x User Manual 523 clears AERR bit by writing 0 to it ...