NXP Semiconductors K22F series, Reference Manual, Page: 850 / 1407

36.4.3 DAC Status Register (DACx_SR)
If DMA is enabled, the flags can be cleared automatically by DMA when the DMA
request is done. Writing 0 to a field clears it whereas writing 1 has no effect. After reset,
DACBFRPTF is set and can be cleared by software, if needed. The flags are set only
when the data buffer status is changed.
Address: Base a 20h offset
Bit 7 6 5 4 3 2 1 0
Read 0 DACBFWM
F
DACBFRPT
F
DACBFRPB
F
Write
Reset 0 0 0 0 0 0 1 0
DACx_SR field descriptions
Field Description
7–3
Reserved
This field is reserved.
This read-only field is reserved and always has the value 0.
2
DACBFWMF
DAC Buffer Watermark Flag
This bit is set if the remaining FIFO data is less than the watermark setting. It is cleared automatically by
writing data into FIFO by DMA or CPU. Write to this bit is ignored in FIFO mode.
0 The DAC buffer read pointer has not reached the watermark level.
1 The DAC buffer read pointer has reached the watermark level.
1
DACBFRPTF
DAC Buffer Read Pointer Top Position Flag
In FIFO mode, it is FIFO nearly empty flag. It is set when only one data remains in FIFO. Any DAC trigger
does not increase the Read Pointer if this bit is set to avoid any possible glitch or abrupt change at DAC
output. It is cleared automatically if FIFO is not empty.
0 The DAC buffer read pointer is not zero.
1 The DAC buffer read pointer is zero.
0
DACBFRPBF
DAC Buffer Read Pointer Bottom Position Flag
In FIFO mode, it is FIFO FULL status bit. It means FIFO read pointer equals Write Pointer because of
Write Pointer increase. If this bit is set, any write to FIFO from either DMA or CPU is ignored by DAC. It is
cleared if there is any DAC trigger making the DAC read pointer increase. Write to this bit is ignored in
FIFO mode.
0 The DAC buffer read pointer is not equal to C2[DACBFUP].
1 The DAC buffer read pointer is equal to C2[DACBFUP].
Memory map/register definition
K22F Sub-Family Reference Manual, Rev. 4, 08/2016
850 NXP Semiconductors