Cirrus Logic EP93xx - Manual (Page 756)

25-18 DS785UM1
Copyright 2007 Cirrus Logic
Analog Touch Screen Interface
EP93xx User’s Guide
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5
2
5
25
Mask:
03FF_FFFF
Definition:
Analog Touch screen Setup and Deviation Register.
Bit Descriptions:
RSVD: Reserved. Unknown during read.
TDTCT: TouchDetect Read only bit. Allows the ARM Core the
ability to read the state of the TOUCH_DETECT line.
SDLY: Defines the amount of settling time between A / D samples
from 3 to 1024
μ
sec assuming a 1 MHz clock.
NSMP: Defines the number of samples averaged per X or Y
reading.
00 - 4 samples
01 - 8 samples
10 - 16 samples
11 - 32 samples
DEV: Defines the amount of max to min range deviation in a
sample set allowed before rejection.
000 - +/- 4 LSBs
001 - +/- 8 LSBs
010 - +/- 12 LSBs
011 - +/- 16 LSBs
100 - +/- 24 LSBs
101 - +/- 32 LSBs
110 - +/- 64 LSBs
111 - +/- 128 LSBs
ENABLE: Enables the touch screen scanning state machine.
0 - Disabled.
1 - Enabled.
DLY: Defines the amount of settling time between changes to
the touch screen drive conditions from 3 to 1024
μ
s
assuming a 1 MHz clock.