Touchscreen Controller Registers
12.5.1.10 CTRL Register (offset = 40h) [reset = 0h]
CTRL is shown in
and described in
.
@TSC_ADC_SS Control Register
Figure 12-14. CTRL Register
31
30
29
28
27
26
25
24
Reserved
R-0h
23
22
21
20
19
18
17
16
Reserved
R-0h
15
14
13
12
11
10
9
8
Reserved
HW_preempt
HW_event_mapping
R-0h
R/W-0h
R/W-0h
7
6
5
4
3
2
1
0
Touch_Screen_Enabl
AFE_Pen_Ctrl
Power_Down
ADC_Bias_Select
StepConfig_WriteProt
Step_ID_tag
Enable
e
ect_n_active_low
R/W-0h
R/W-0h
R/W-0h
R/W-0h
R/W-0h
R/W-0h
R/W-0h
LEGEND: R/W = Read/Write; R = Read only; W1toCl = Write 1 to clear bit; -n = value after reset
Table 12-14. CTRL Register Field Descriptions
Bit
Field
Type
Reset
Description
31-10
Reserved
R
0h
9
HW_preempt
R/W
0h
0 = SW steps are not pre-empted by HW events.
1 = SW steps are pre-empted by HW events
8
HW_event_mapping
R/W
0h
0 = Map HW event to Pen touch irq (from AFE).
1 = Map HW event to HW event input.
7
Touch_Screen_Enable
R/W
0h
0 = Touchscreen transistors disabled.
1 = Touchscreen transistors enabled
6-5
AFE_Pen_Ctrl
R/W
0h
These two bits are sent directly to the AFE Pen Ctrl inputs.
Bit 6 controls the Wiper touch (5 wire modes)Bit 5 controls the X+
touch (4 wire modes)User also needs to make sure the ground path
is connected properly for pen interrupt to occur (using the
StepConfig registers)Refer to section 4 interrupts for more
information
4
Power_Down
R/W
0h
ADC Power Down control.
0 = AFE is powered up (default).
1 = Write 1 to power down AFE (the tsc_adc_ss enable (bit 0)
should also be set to off)
3
ADC_Bias_Select
R/W
0h
Select Bias to AFE.
0 = Internal.
1 = Reserved.
2
StepConfig_WriteProtect_
R/W
0h
0 = Step configuration registers are protected (not writable).
n_active_low
1 = Step configuration registers are not protected (writable).
1
Step_ID_tag
R/W
0h
Writing 1 to this bit will store the Step ID number with the captured
ADC data in the FIFO.
0 = Write zeroes.
1 = Store the channel ID tag.
0
Enable
R/W
0h
TSC_ADC_SS module enable bit.
After programming all the steps and configuration registers, write a
1to this bit to turn on TSC_ADC_SS.
Writing a 0 will disable the module (after the current conversion).
1048
Touchscreen Controller
SPRUH73H – October 2011 – Revised April 2013
Copyright © 2011–2013, Texas Instruments Incorporated