Freescale Semiconductor Evaluation Board MPR031/2 for 2- or 3-pad touch sensor controllers DEMOMPR031 DEMOMPR031 データシート
製品コード
DEMOMPR031
MPR03X
Sensors
14
Freescale Semiconductor
5.4
Baseline Values
In addition to the second level filter data, the data from the baseline filter (or third level filter) is also displayed. In this case, the
least two significant bits are removed before the 10-bit value is displayed in the register.
least two significant bits are removed before the 10-bit value is displayed in the register.
5.4.1
The Baseline Value register contains the third level filtered data on each of the electrodes. It is a truncated 10 bit A/D value
displayed in the 8 bit register. The address of the ELE0 Baseline Value register is 0x1A. The address of the ELE1 Baseline Value
register is 0x1B. The address of the ELE2 Baseline Value register is 0x1C.
displayed in the 8 bit register. The address of the ELE0 Baseline Value register is 0x1A. The address of the ELE1 Baseline Value
register is 0x1B. The address of the ELE2 Baseline Value register is 0x1C.
Figure 20. Filtered Data High Register
7
6
5
4
3
2
1
0
R
BV
W
Reset:
0
0
0
0
0
0
0
0
= Unimplemented
Table 9. Filtered Data High Register Field Descriptions
Field
Description
7:0
BV
BV
Baseline Value – The Baseline Value byte displays the higher 8 bits of the 10 bit
baseline value.
00000000 Encoding 0 – The 10 bit baseline value is between 0 and 3.
~
11111111 Encoding 255 – The 10 bit baseline value is between 1020 and 1023.
baseline value.
00000000 Encoding 0 – The 10 bit baseline value is between 0 and 3.
~
11111111 Encoding 255 – The 10 bit baseline value is between 1020 and 1023.