SLAU367P October 2012 – April 2020 MSP430FR5041 , MSP430FR5043 , MSP430FR50431 , MSP430FR5847 , MSP430FR58471 , MSP430FR5848 , MSP430FR5849 , MSP430FR5857 , MSP430FR5858 , MSP430FR5859 , MSP430FR5867 , MSP430FR58671 , MSP430FR5868 , MSP430FR5869 , MSP430FR5870 , MSP430FR5872 , MSP430FR58721 , MSP430FR5887 , MSP430FR5888 , MSP430FR5889 , MSP430FR58891 , MSP430FR5922 , MSP430FR59221 , MSP430FR5947 , MSP430FR59471 , MSP430FR5948 , MSP430FR5949 , MSP430FR5957 , MSP430FR5958 , MSP430FR5959 , MSP430FR5962 , MSP430FR5964 , MSP430FR5967 , MSP430FR5968 , MSP430FR5969 , MSP430FR5969-SP , MSP430FR59691 , MSP430FR5970 , MSP430FR5972 , MSP430FR59721 , MSP430FR5986 , MSP430FR5987 , MSP430FR5988 , MSP430FR5989 , MSP430FR5989-EP , MSP430FR59891 , MSP430FR5992 , MSP430FR5994 , MSP430FR59941 , MSP430FR6005 , MSP430FR6007 , MSP430FR6035 , MSP430FR6037 , MSP430FR60371 , MSP430FR6041 , MSP430FR6043 , MSP430FR60431 , MSP430FR6045 , MSP430FR6047 , MSP430FR60471 , MSP430FR6820 , MSP430FR6822 , MSP430FR68221 , MSP430FR6870 , MSP430FR6872 , MSP430FR68721 , MSP430FR6877 , MSP430FR6879 , MSP430FR68791 , MSP430FR6887 , MSP430FR6888 , MSP430FR6889 , MSP430FR68891 , MSP430FR6920 , MSP430FR6922 , MSP430FR69221 , MSP430FR6927 , MSP430FR69271 , MSP430FR6928 , MSP430FR6970 , MSP430FR6972 , MSP430FR69721 , MSP430FR6977 , MSP430FR6979 , MSP430FR69791 , MSP430FR6987 , MSP430FR6988 , MSP430FR6989 , MSP430FR69891
22.2.8 AUTOSSDIS (Auto Conversion Start Disable) Bit
The SDHS supports two different ways to start data conversion after power up (see Table 22-7).
Table 22-7 Conversion Control Mode
| Mode | Control | Power up SDHS | Conversion Start | Operation | ||
|---|---|---|---|---|---|---|
| SDHSCTL0.AUTOSSDIS | When SDHSCTL0.TRGSRC = 0 | When SDHSCTL0.TRGSRC = 1 | When SDHSCTL0.TRGSRC = 0 | When SDHSCTL0.TRGSRC = 1 | ||
| Auto conversion start: disabled | 1 | SDHSCTL4.SDHSON = 1 | ASQ_ACQARM = 1 (from ASQ) | SDHSCTL5.SSTART = 1 | ASQ_ACQTRG = 1 (from ASQ) | Power up and conversion start are controlled separately. The SDHS settling time must be satisfied before asserting the conversion start signal. |
| Auto conversion start: enabled | 0 | SDHSCTL4.SDHSON = 1 | ASQ_ACQARM = 1 (from ASQ) | Not Required | Not Required | Data conversion automatically begins after power up. The SDHS settling time is automatically applied. |
When SDHSCTL0.AUTOSSDIS = 0, automatic conversion start is enabled. Conversion automatically starts after the SDHS is powered on. During power up, the SDHS settling time is monitored and when the SDHS is settled, conversion automatically begins. See Figure 22-21 for the sequence of conversion start and stop in this mode.
When SDHSCTL0.AUTOSSDIS = 1, auto conversion start is disabled (default after reset). In this mode, power control and conversion control are separate (see Figure 22-22). This mode can be used when data conversion start time needs to be precisely controlled. It is important that the SDHS settling time must has satisfied before data conversion start signal is applied. If the data conversion start trigger signal is applied during the settling time, the SDHS data conversion is automatically delayed until the settling time has passed. SDHS settling time is The greater of the PGA settling time and SDHS modulator settling time. See the device-specific data sheet for the settling times.
Figure 22-21 Conversion Start and Stop When SDHSCTL0.AUTOSSDIS = 0 
Figure 22-22 Conversion Start and Stop When SDHSCTL0.AUTOSSDIS = 1