GD32W51x User Manual
735
31:21
Reserved
Must be kept at reset value
20:16
FMSZ[4:0]
Flash memory size
This field defines the size of external memory using the follow ing formula:
Number of bytes in Flash memory = 2
[FMSZ+1]
FMSZ+1 is effectively the number of address bits in the Flash memory. The Flash
memory capacity can be up to 4GB in indirect mode, w hile it is limited to 256MB in
memory mapped mode.
This field can be modified only w hen BUSY = 0.
15:11
Reserved
Must be kept at reset value
10:8
CSHC[2:0]
Chip select high cycle
CSHC+1 defines the minimum number of CLK cycles w hich the chip select(CSN)
must stay high betw een tw o command sequences.
0: CSN stays high for at least 1 cycle betw een Flash memory commands
1: CSN stays high for at least 2 cycles betw een Flash memory commands
...
7: CSN stays high for at least 8 cycles betw een Flash memory commands
This field can be modified only w hen BUSY = 0.
7:1
Reserved
Must be kept at reset value
0
CKMOD
This bit indicates the SCK level w hen QSPI is free
0: CLK must stay low w hile CSN is high (QSPI is free).
1: CLK must stay high w hile CSN is high (QSPI is free).
This field can be modified only w hen BUSY = 0.
22.11.3.
Status register (QSPI_STAT)
Address offset: 0x08
Reset value: 0x0000 0004
This register can be accessed by word (32-bit).
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
Reserved
DMAEN
rw
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
Reserved
WSIE TMOUTIE
SMIE
FTIE
TCIE
TERRIE
WS
TMOUT
SM
FT
TC
TERR
rw
rw
rw
rw
rw
rw
r
r
r
r
r
r
Bits
Fields
Descriptions
31:17
Reserved
Must be kept at reset value
16
DMAEN
DMA enable
In indirect mode, DMA can be used to transfer data via QSPI_DA TA. DMA transfers