GD32F403xx User Manual
595
11: Mode D access
27:20
Reserved
Must be kept at reset value.
19:16
WBUSLAT[3:0]
Bus latency
Bus latency added at the end of each write transaction to match with the minimum
time between consecutive transactions.
0x0: Bus latency = 1 * HCLK period
0x1: Bus latency = 2 * HCLK period
……
0xF: Bus latency = 16 * HCLK period
15:8
WDSET[7:0]
Data setup time
This field is meaningful only in asynchronous access.
0x00: Reserved
0x01: Data setup time = 2 * HCLK period
……
0xFF: Data setup time = 256 * HCLK period
7:4
WAHLD[3:0]
Address hold time
This field is used to set the time of address hold phase, which onl y used in mode
D and multiplexed mode.
0x0: Reserved
0x1: Address hold time = 2 * HCLK
……
0xF: Address hold time = 16 * HCLK
3:0
WASET[3:0]
Address setup time
This field is used to set the time of address setup phase.
Note:
Meaningful only in asynchronous access of SRAM,ROM,NOR Flash
0x0: Address setup time = 1 * HCLK
0x1: Address setup time = 2 * HCLK
……
0xF: Address setup time = 16 * HCLK
21.4.2.
NAND Flash/PC Card controller registers
NAND Flash/PC Card control registers (EXMC_NPCTLx) (x=1, 2, 3)
Address offset: 0x40 + 0x20 * x, (x = 1, 2, and 3)
Reset value: 0x0000 0018
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
ECCSZ[2:0]
ATR[3]
rw
rw