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GD32F403xx User Manual
567
EXMC Pin
Direction
Mode
Functional description
(muxed)
Input/output
Async/Sync
(non-muxed)
Data bus
EXMC_NE[x]
Output
Async/Sync
Chip selection,
x=0/1/2/3
EXMC_NOE
Output
Async/Sync
Read enable
EXMC_NWE
Output
Async/Sync
Write enable
EXMC_NWAIT
Input
Async/Sync
Wait input signal
EXMC_NL(NADV)
Output
Async/Sync
Address valid
Table 21-2. PSRAM non-muxed signal description
EXMC Pin
Direction
Mode
Functional description
EXMC_CLK
Output
Sync
Clock signal for sync
EXMC_A[25:0]
Output
Async/Sync
Address Bus
EXMC_D[15:0]
Input/output
Async/Sync
Data Bus
EXMC_NE[x]
Output
Async/Sync
Chip selection, x=0/1/2/3
EXMC_NOE
Output
Async/Sync
Read enable
EXMC_NWE
Output
Async/Sync
Write enable
EXMC_NWAIT
Input
Async/Sync
Wait input signal
EXMC_NL(NADV)
Output
Async/Sync
Latch enable (address
valid enable, NADV)
EXMC_NBL[1]
Output
Async/Sync
Upper byte enable
EXMC_NBL[0]
Output
Async/Sync
Lower byte enable
Supported memory access mode
Table below shows an example of the supported devices type, access modes and
transactions when the memory data bus is 16-bit for NOR, PSRAM and SRAM.
Table 21-3. EXMC bank 0 supports all transactions
Memory
Access Mode
R/W
AHB
Transaction
Size
Memory
Transaction
Size
Comments
NOR Flash
Async
R
8
16
Async
R
16
16
Async
W
16
16
Async
R
32
16
Split into 2 EXMC
accesses
Async
W
32
16
Split into 2 EXMC
accesses
Sync
R
16
16
Sync
R
32
16
PSRAM
Async
R
8
16
Содержание GD32F403 Series
Страница 1: ...GigaDevice Semiconductor Inc GD32F403xx Arm Cortex M4 32 bit MCU User Manual Revision 2 6 Jul 2022 ...
Страница 177: ...GD32F403xx UserManual 177 Peripheral Channel 0 Channel 1 Channel 2 Channel 3 Channel 4 SDIO SDIO ...
Страница 217: ...GD32F403xx UserManual 217 ensures that no conversion is in progress ...