Texas Instruments MSC1210 manual Shift Summation Count

Models: MSC1210

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Summation/Shifter Register

SSCON1 and SSCON0 (SSCON.7 and SSCON.6, respectively) control which of the four modes the summation register will operate in.

SCNT0, SCNT1, and SCNT2 (SSCON.3 through SSCON.5) are used to indi- cate how many ADC samples should be obtained and summed to the summa- tion register. The number of samples that will be obtained and added are:

SCNT2

SCNT1

SCNT0

Summation Count

 

 

 

 

0

0

0

2

 

 

 

 

0

0

1

4

 

 

 

 

0

1

0

8

 

 

 

 

0

1

1

16

 

 

 

 

1

0

0

32

 

 

 

 

1

0

1

64

 

 

 

 

1

1

0

128

 

 

 

 

1

1

1

256

 

 

 

 

When the requested number of samples have been obtained and summed, a summation auxiliary interrupt will be triggered, if enabled.

SHF2, SHF1, and SHF0 (SSCON.0 through SSCON.2) are used to indicate by what value the final summation value should be divided. Specifically, the value indicates how many bits to the right the final summation value will be shifted, less one. Thus, a shift count of 0 reflects a final right shift by 1, which equates to a divide by 2. A shift count of 4 reflects a final right shift by 5, which equates to a divide by 32.

SHF2

SHF1

SHF0

Shift

Summation Count

 

 

 

 

 

0

0

0

1

2

 

 

 

 

 

0

0

1

2

4

 

 

 

 

 

0

1

0

3

8

 

 

 

 

 

0

1

1

4

16

 

 

 

 

 

1

0

0

5

32

 

 

 

 

 

1

0

1

6

64

 

 

 

 

 

1

1

0

7

128

 

 

 

 

 

1

1

1

8

256

 

 

 

 

 

Analog-to-Digital Converter

12-17

 

Page 153
Image 153
Texas Instruments MSC1210 manual Shift Summation Count