
Hardware Description
3-40
Copyright © ARM Limited 2000. All rights reserved.
3.12.1
Touch screen controller
To use the touch screen controller within the UCB1200, you must connect the touch
screen to the CPU board using the connector JP3.
This touch screen uses a four-wire interface consisting of the signals
UCB_TSPY
,
UCB_TSPX
,
UCB_TSMY
, and
UCB_TSM
.
The controller carries out three types of
measurement:
•
X-Y position
•
pressure
•
plate resistance
The measurement type is defined in the touch screen control register. Measurements
are typically taken by carrying out a sequence of:
1.
Selecting the mode.
2.
Selecting the appropriate input to the ADC.
3.
Reading the value from the ADC data register.
The section Programming the UCB1200 on page 4-27 provides more information about
interface timing.
3.12.2
Audio codec
The audio codec is a 12-bit sigma-delta codec with programmable sample rates. It has
outputs capable of directly driving a speaker and microphone, with programmable
voltage levels.
The audio sample rate is derived from the SIB clock input to the UCB1200. The sample
rate is programmable in the audio control register A. The sample rate is given by the
following equation:
The audio divisor must be greater than 5 and less than 128.
The UCB1200 samples both edges of the clock. The clock signal must have a 50% duty
cycle if an odd divisor is used.
The audio codec drives the on-board microphone and speaker sockets, and the
microphone and speaker on the distribution board, if connected. The distribution board
devices are disconnected if external devices are connected into the jack sockets. The
connector JP48 provides a +3V power source for active microphones.
F
sa
2 F
sibclk
⋅
(
)
64 audio_divisor
⋅
(
)
------------------------------------------------
=
Summary of Contents for Prospector P1100
Page 1: ...ARM DUI 0122A Prospector P1100 User Guide ...
Page 4: ...iv Copyright ARM Limited 2000 All rights reserved ARM DUI 0122A ...
Page 86: ...Hardware Description 3 54 Copyright ARM Limited 2000 All rights reserved ARM DUI 0122A ...
Page 140: ...Connector reference A 18 Copyright ARM Limited 2000 All rights reserved ARM DUI 0122A ...