Maxim Integrated MAX32600, Руководство пользователя

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MAX32600 User’s Guide Analog Front End 8.3 ADC
adc_mode Mode Description
1000b High Performance Channel Scan Measure adc_smpl_cnt samples one time per channel.
1001b Low Power Channel Scan Measure adc_smpl_cnt samples with adc_sleep_cnt delay between channels. Single pass through
scan channels.
1010b High Performance Continuous Channel Scan High Performance Channel Scan continuously. When all channels have been measured scanning
begins again with the first scan channel.
1011b Low Power Continuous Channel Scan Low Power Channel Scan continuously. When all channels have been measured scanning begins
again with the first scan channel.
8.3.4.6 Interrupts
ADC interrupts are enabled using the ADC_INTR register. Refer to System Configuration and Management for details on setting up and configuring interrupts.
Out of Range Interrupts
The MAX32600 ADC supports an upper and lower set point to generate out of range interrupts if a measured sample goes above or below a configured threshold.
The out of range support simplifies monitoring an input signal for a threshold and allows the CPU to only wake when a set condition occurs.
Interrupt support is provided for a measured value being above the upper limit, below the lower limit, or outside the range of the two limits combined. To set the lower
threshold, write the desired value to the register field
ADC_LIMIT.lo_limit ; ADC_LIMIT.hi_limit is used to set the upper threshold.
The interrupt flag ADC_INTR.hi_rng is set by hardware when a measured value exceeds the upper limit threshold. Similarly, the ADC_INTR.lo_rng is set when a
measured value falls below the lower limit threshold. The ADC_INTR.out_rng flag is set when either of the previous conditions occur.
ADC Output FIFO
The MAX32600 ADC includes a 32-level-deep output FIFO with each entry 16 bits wide. The FIFO is read through the ADC_OUT.data_reg register. Multiple reads
to the register will return the next 16-bit value. The ADC interface can generate a variety of FIFO interrupts if enabled.
There are several status fields and interrupt flags provided to assist the application in handling the ADC Output FIFO:
• ADC_CTRL0.adc_fifo_full – set by hardware when the FIFO level has exceeded the almost full threshold level.
• ADC_TG_CTRL1.fifo_af_cnt – 4-bit field used to set the threshold for almost full warning.
• ADC_CTRL0.adc_fifo_empty – Reading a value of 1 indicates the ADC FIFO is empty.
Rev.1.3 April 2015 Maxim Integrated Page 414