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GD32F403xx User Manual
202
mpling
ratio
Raw
data
OVSS=
0000
shift
OVSS=
0001
shift
OVSS=
0010
shift
OVSS=
0011
shift
OVSS=
0100
shift
OVSS=
0101
shift
OVSS=
0110
shift
OVSS=
0111
shift
OVSS=
1000
2x
0x1FFE 0x1FFE 0x0FFF 0x07FF 0x03FF 0x01FF 0x00FF 0x007F 0x003F 0x001F
4x
0x3FFC 0x3FFC 0x1FFE 0x0FFF 0x07FF 0x03FF 0x01FF 0x00FF 0x007F 0x003F
8x
0x7FF8 0x7FF8 0x3FFC 0x1FFE 0x0FFF 0x07FF 0x03FF 0x01FF 0x00FF 0x007F
16x
0xFFF0 0xFFF0 0x7FF8 0x3FFC 0x1FFE 0x0FFF 0x07FF 0x03FF 0x01FF 0x00FF
32x
0x1FFE0 0xFFE0 0xFFF0 0x7FF8 0x3FFC 0x1FFE 0x0FFF 0x07FF 0x03FF 0x01FF
64x
0x3FFC0 0xFFC0 0xFFE0 0xFFF0 0x7FF8 0x3FFC 0x1FFE 0x0FFF 0x07FF 0x03FF
128x 0x7FF80 0xFF80 0xFFC0 0xFFE0 0xFFF0 0x7FF8 0x3FFC 0x1FFE 0x0FFF 0x07FF
256x 0xFFF00 0xFF00 0xFF80 0xFFC0 0xFFE0 0xFFF0 0x7FF8 0x3FFC 0x1FFE 0x0FFF
The conversion timings in oversampled mode do not change compared to standard
conversion mode: the sampling time remains equal throughout the oversampling sequence.
New data is supplied every N conversions, and the equivalent delay is equal to:
N*t
ADC
=N*(t
SMPL
+t
CONV
) (3-1)
12.5.
ADC sync mode
In devices with more than one ADC, the ADC sync mode can be used. In ADC sync mode,
the conversion starts alternately or simultaneously triggered by ADC0 to ADC1, according to
the sync mode configurated by the SYNCM[3:0] bits in ADC1_CTL0 register.
In sync mode, when configure the conversion which is triggered by an external event, the
ADC1 must be configured as triggered by the software. However, the external trigger must
be enabled for ADC0 and ADC1.
The f ollowing modes can be configured in
Table 12-7. ADC sync mode table
.
Table 12-7. ADC sync mode table
SYNCM[3: 0]
mode
0000
Free mode
0110
Routine parallel mode
0111
Routine follow-up fast mode
1000
Routine follow-up slow mode
In ADC sync mode, the DMA bit must be set even if it is not used; the converted data of ADC1
routine
channel can be read from the ADC0 data register.