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GD32F20x User Manual
721
Figure 25-33. Read access when FIFO not hit (BRSTRD=1, CL=2, SDCLK=2, PIPED=2)
@0x4
Data1
@0x8
Data2
@0xC
Data3
...
...
AHB Master IF
SDRAM
Memroy
Read @0x0
Data0 @0x0
Data1 @0x4
Data2 @0x8
Data3 @0xc
Read FIFO
Figure 25-34. Read access when FIFO hit (BRSTRD=1)
@0x4
Data1
@0x8
Data2
@0xC
Data3
...
...
AHB Master IF
SDRAM
Memroy
Read @0x8
Read FIFO
Data2 @0x8
The read FIFO will be flushed and ready to be filled with new data, when a write access or a
precharge command occurs.
The address decoder sub-module translate the address of the AHB bus address to chip select,
internal bank address, row address and column address according to the configuration of
external memory device.
The active cache sub-module records whether the internal banks (up to 8) are in the active
state. When an internal bank is in active state, the corresponding row address is also recorded.
When an AHB access or an auto-refresh command is issued, the RW split module will look
up this record and decide whether to generate the Active/Precharge commands or not.
Before read/write operation, the targeted row must be activated, the value of EXMC_A[15:14]
selects the bank, and EXMC_A[12:0] select the row. The selected row remains active until a
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 ...