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Nations Technologies Inc.
Tel
:
+86-755-86309900
:
Address: Nations Tower, #109 Baoshen Road, Hi-tech Park North.
Nanshan District, Shenzhen, 518057, P.R.China
Figure 9-10 Schematic diagram of synchronous injection mode conversion of 4 channels
9.9.4
Fast alternate mode
This mode is for regular sequences (usually one channel). The external trigger comes from the multiplexer of ADC1,
which is determined by ADC_CTRL2.EXTRSEL[2:0]. When the trigger occurs, ADC2 converts immediately and
ADC1 starts converting after 7 ADC clock cycles. If ADC_CTRL2.CTU is set for ADC1 and ADC2, then the selected
regular sequence will be converted continuously.
The converted data will be stored in the ADC_DAT register. The high halfword of ADC_DAT is the conversion data
of ADC2, and the low halfword of ADC_DAT is the conversion data of ADC1. If ADC1 or ADC2 sets
ADC_CTRL1.ENDCIEN, when the conversion of the regular sequence of ADC1 or ADC2 is completed, an ENDC
interrupt will be generated. At this time, if ADC_CTRL2.ENDMA is set, a DMA transfer request can be generated,
and the data of ADC_DAT can be passed through DMA transfers to SRAM.
Note:
1. When using fast alternate mode, make sure that no injection channel is externally triggered.
2. The sampling time must be less than 7 ADC clock cycles to avoid overlapping sampling cycles when ADC1 and
ADC2 convert the same channel.
CH1
CH2
CH3
CH4
CH4
CH3
CH2
CH1
ADC1
ADC2
Conversion
Sampling
Trigger
JENDC