Information
TSIx_GENCS field descriptions (continued)
Field Description
11101 30 times per electrode
11110 31 times per electrode
11111 32 times per electrode
18–16
PS
Electrode Oscillator prescaler. .
This bit-field can only be changed if the TSI module is disabled (TSIEN bit = 0)
000 Electrode Oscillator Frequency divided by 1
001 Electrode Oscillator Frequency divided by 2
010 Electrode Oscillator Frequency divided by 4
011 Electrode Oscillator Frequency divided by 8
100 Electrode Oscillator Frequency divided by 16
101 Electrode Oscillator Frequency divided by 32
110 Electrode Oscillator Frequency divided by 64
111 Electrode Oscillator Frequency divided by 128
15
EOSF
End of Scan Flag.
This flag is set when all active electrodes are scanned is ended after a scan trigger. Writing "1" to this bit
will clear the flag to 0.
14
OUTRGF
Out of Range Flag.
This flag is set if the result register of the low power enabled electrode is outside the range defined by the
TSI_THRESHOLD register. This flag is only set when the TSI is in low power mode. It can be read once
the CPU wakes up. Writing "1" to this bit will clear the flag to 0.
13
EXTERF
External Electrode error occurred
This flag is set when an active electrode has a result register either 0x0000 or 0xFFFF. Writing "1" to this
bit will clear the flag to 0.
0 No fault happend on TSI electrodes
1 Short to VDD or VSS was detected on one or more electrodes.
12
OVRF
Overrun error Flag. This flag is set when a scan trigger occurs while a scan is still in progress. Writing "1"
to this bit will clear the flag to 0.
0 No over run.
1 Over Run occurred.
11–10
Reserved
This read-only field is reserved and always has the value zero.
9
SCNIP
Scan In Progress status
"1" indicates a scanning process is in progress,this bit is read-only and changes automatically by the TSI
model.
8
SWTS
Software Trigger Start
Write a "1" to this bit will start a scan sequence and write a "0" to this bit has no effect.
7
TSIEN
Touch Sensing Input Module Enable
Table continues on the next page...
Chapter 48 Touch sense input (TSI)
K20 Sub-Family Reference Manual, Rev. 2, Feb 2012
Freescale Semiconductor, Inc. 1197