GD32W51x User Manual
733
21
Reserved
Must be kept at reset value
20:16
FL[4:0]
FIFO level
This field gives the number of valid bytes w hich are being held in the FIFO in indirect
mode. In memory-mapped mode and in automatic status polling mode, FL is zero.
15
FMC_MOD
Busy in FMC
mode
This bit is set w hen a command is transferring in FMC
mode. This bit is cleared
once the operation w ith the Flash memory in FMC
mode is completed.
14
BUSY
Busy
This bit is set w hen a command is transferring. This bit is cleared once the operation
w ith the Flash memory is finished and the FIFO is empty.
13:12
Reserved
Must be kept at reset value
11:8
FTL [3:0]
FIFO threshold level
This bits are useful in indirect mode, the threshold number of bytes in the FIFO that
w ill cause the FIFO threshold flag to be set.
In indirect w rite mode (FMOD = 00):
0: FT is set if there are 1 or more free bytes available to be w ritten to in the FIFO
1: FT is set if there are 2 or more free bytes available to be w ritten to in the FIFO
...
15: FT is set if there are 16 free bytes available to be w ritten to in the FIFO
In indirect read mode (FMOD = 01):
0: FT is set if there are 1 or more valid bytes that can be read from the FIFO
1: FT is set if there are 2 or more valid bytes that can be read from the FIFO
...
15: FT is set if there are 16 valid bytes that can be read from the FIFO
If DMAEN = 1, then the DMA controller for the corresponding channel must be
disabled before changing the FTL value.
7
Reserved
Must be kept at reset value
6
SCKDEN
SCK delay enable w hen read data from flash, it is only useful w hen sample shift is
1
0: SCK delay disabled
1: SCK delay enabled
5:4
SSAMPLE[1:0]
Sample shift
By default, the QSPI samples data 1/2 of a SCK cycle after the data is driven by the
Flash memory. This bit allow s the data is to be sampled later in order to account for
external signal delays.
0: No shift
1: 1/2 cycle shift
2: 1 cycle shift
3: Reserved