Looking at below table in datasheet I am wondering if only channels 0 and 1 do support pre-sampling. What about the other channels?
Pre-sampling works for both ADC (ADC_0 and ADC_1) and for all the 16 channels (16 for each ADC)
The pre-sampling registers need to be set correctly:
External channels 0-8 and 11-14 (PSCR.PREVAL0)
Internal channels 9, 10 and 15 (PSCR.PREVAL1)
Note: ADC_0/1 channel 9 is reserved for factory test, but nevertheless the pre-sampling works.
In attached test code used following configurations are valid for:
- ADC_0: Ch_0 .. Ch_15
- ADC_1: Ch_0 .. Ch_15
- ADC_0 = VDD_HV_ADR0
- ADC_1 = VDD_HV_ADR1
- PRECONV = 1 // The ADC will perform a pre-sampling followed by a conversion (the sampling is bypassed, so the conversion result is that of the pre-sampled value)
Moreover, it is possible to show the conversion results (VDD=0xFFF in 12 bits) using a PC connection (HYPER TERMINAL), a RS232 cable and the mini module.
The communication parameters are:
- Baud Rate = 19200
- Data bits = 8
- Parity = None
- Stop bit = 1
- PAD_LIN0_TXD PCR = 18
- PAD_LIN0_RXD PCR = 19