TSC2301EVM Touch Screen Controller Evaluation Module User’s Guide November 2002 Data Acquisition Products SLAU098
IMPORTANT NOTICE Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, modifications, enhancements, improvements, and other changes to its products and services at any time and to discontinue any product or service without notice. Customers should obtain the latest relevant information before placing orders and should verify that such information is current and complete.
EVM IMPORTANT NOTICE Texas Instruments (TI) provides the enclosed product(s) under the following conditions: This evaluation kit being sold by TI is intended for use for ENGINEERING DEVELOPMENT OR EVALUATION PURPOSES ONLY and is not considered by TI to be fit for commercial use.
EVM WARNINGS AND RESTRICTIONS It is important to operate this EVM within the input voltage range of 6 VDC to 12 VDC and output voltage of 3 VDC described in the EVM User’s Guide. Exceeding the specified input range may cause unexpected operation and/or irreversible damage to the EVM. If there are questions concerning the input range, please contact a TI field representative prior to connecting the input power.
How to Use This Manual Preface Read This First About This Manual This users guide describes the function and operation of the TSC2301 touch screen controller evaluation module. This manual will help you quickly set up the evaluation board and its accompanying software, so that you may rapidly test and evaluate the TSC2301. A complete circuit description, as well as schematic diagram and bill of materials are included.
Related Documentation From Texas Instruments The information in a caution or a warning is provided for your protection. Please read each caution and warning carefully. Related Documentation From Texas Instruments To obtain a copy of any of the following TI documents, call the Texas Instruments literature response center at (800) 477-8924 or the product information center (PIC) at (972) 644-5580. When ordering, please identify this booklet by its title and literature number.
Contents Contents 1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.1 Device Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.2 EVM Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.3 Analog Inputs/Outputs . . . . . . . . . . . . . . . . . . . . . . .
Contents 3.4.3 3.4.4 3.4.5 4 Data Acquisition Screen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-13 Audio Screen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-13 Bass Boost Filter Screen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-16 Physical Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Chapter 1 Introduction The TSC2301 is an advanced touch screen controller, which communicates to a host processor through an SPI serial interface. In addition, a full stereo audio codec is included in the TSC2301, and audio data is communicated to the device over an I2S bus. The TSC2301EVM accesses both of these buses through the use of a USB microcontroller, which provides a way to generate data for both buses from a PC running Windows 98SE, 2000, or XP. Topic Page 1.1 Device Characteristics . . . .
Device Characteristics 1.1 Device Characteristics The TSC2301 is a complete PDA analog interface circuit. It contains a complete 12-bit A/D resistive touch screen converter, including drivers, the control to measure touch pressure, a 4-by-4 matrix keyboard controller, and 8-bit D/A converter output for LCD contrast control. The TSC2301 interfaces to the host controller through a standard SPI serial interface.
Analog Inputs/Outputs 1.3 Analog Inputs/Outputs Touch screen inputs are provided to the controller through J13. This connector is standard on 3M Touch Systems (formerly MicroTouch) TouchTek 4 touch screens. Alternate touch screen input connections are provided on the J12 terminal block. The other analog inputs are brought onto the board through the J14 terminal block. The AUX1 and AUX2 inputs must be between 0 V and 3.3 V, while the battery inputs, VBAT1 and VBAT2 may range from 0 V to 6 V. 1.
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Chapter 2 Getting Started This chapter guides you through unpacking your EVM, and setting it up so you can begin working with it immediately. Topic Page 2.1 Unpacking the EVM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2 2.2 Default Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2 2.3 Quick Start . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Unpacking the EVM 2.1 Unpacking the EVM Unpacking the TSC2301EVM, check to make sure you received all the material that should be in the box. The EVM kit should include the following: - TSC2301EVM board, PWB 6438187 - CD-ROM, 6438190 If any of these components is missing, contact Texas Instruments for a replacement. 2.2 Default Configuration The TSC2301EVM features a few simple means of configuring its operation. The default settings for these items are shown in Table 2-1.
Quick Start Figure 2-1. Default Software Screen In order to use the touch screen features, a 4-wire resistive touch screen must be connected to J12 or J13 of the TSC2301EVM.
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Chapter 3 Operation This chapter describes each function of the TSC2301 evaluation kit and how to use the accompanying software to control and use the TSC2301. Topic Page 3.1 Jumpers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2 3.2 I/O Connectors and Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3 3.3 Circuit Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Jumpers 3.1 Jumpers The following table shows the function of each jumper on the EVM: Table 3-1. Jumper/Function Reference Reference Designator Setting Function 1 to 2 SPI POL select pin = 0 V 2 to 3 SPI POL select pin = 3.3 V JMP2 1 to 2 JMP3 JMP1 JMP4 JMP5 JMP6 3.1.1 Factory Default Subsection 2 to 3 3.1.1 LINE IN left attenuator Installed 3.1.2 1 to 2 LINE IN right attenuator Installed 3.1.2 1 to 2 MIC BIAS from fixed resistor 2 to 3 MIC BIAS from TSC2301 2 to 3 3.1.
I/O Connector and Signals 3.1.5 EEPROM A1 Select The TSC2301EVM loads its firmware from an onboard EEPROM. In order to use the firmware in this EEPROM, its A1 address line must be pulled low, so JMP6 should stay installed for normal use. This jumper may be removed when firmware updates are to be made. 3.2 I/O Connector and Signals The various connectors on the TSC2301EVM are described in this section. 3.2.1 GPIO Connector This 12-pin header provides access to the six GPIO pins on the TSC2301.
I/O Connector and Signals Table 3-4. Audio Connectors Reference Designator Name Description J3 Line In Stereo line level audio inputs J4 J5 J6 3.2.
I/O Connector and Signals 3.2.6 Audio Data (I2S) Connector The I2S bus, which carries audio data to and from the TSC2301, is brought out to header J10. Table 3-7. Audio Data Connector Reference Designator Audio Data (I2S) connector J10 3.2.7 Description Pin Number Signal Name 1 MCLK 3 BCLK 5 LRCLK 7 I2SDIN 9 I2SDOUT 2,4,6,8,10 Ground External SPI Connector The TSC2301 SPI port is brought out to the J11 header.
Circuit Description Table 3-9. Touch Screen Input Reference Designator J12, J13 3.2.9 Description Touch screen input Pin Number Signal Name Function 1 X- Touch screen X- electrode 2 Y+ Touch screen Y+ electrode 3 X+ Touch screen X+ electrode 4 Y- Touch screen Y- electrode Analog Input Connector The auxiliary and battery inputs to the touch screen controller are brought onto the motherboard through a terminal block, J14. The pinout is shown in Table 3-10. Table 3-10.
Circuit Description Do not drive the external SPI bus when the firmware is loaded and the onboard microprocessor is active. Disable the microprocessor by removing JMP6 and cycling power to the TSC2301EVM if you want to use the external SPI bus. Each signal from the SPI inputs is connected directly to the TSC2301. As such, signals on these pins must not exceed the power supply voltage of the TSC2301, which is 3.3 V on this EVM.
Circuit Description 3.3.4 Keyboard Interface A 4x4 matrix keypad is included with the TSC2301EVM. This keypad connects directly to the TSC2301. No other circuitry is needed since the TSC2301 contains all the keypad control circuitry. 3.3.5 LCD BIas D/A Converter Circuit The TSC2301 contains a current-output D/A converter, which is designed to be used with a two resistor pullup network to turn the current into a voltage.
Program Description 3.4 Program Description After installing the software for the TSC2301EVM as described in Section 2.3, you may begin using it to evaluate and develop with the TSC2301. 3.4.1 Human Interface Screen The program’s interface is a simple, five-tab interface. Clicking on a tab takes you to the functions associated with that tab. The program begins on the Human Interface tab , the default as shown in Figure 3-1. Figure 3-1.
Program Description 3.4.1.1 Touch Screen Section The touch screen box on this screen is updated when a touch is detected on the touch screen. As the touch screen is drawn upon, the motion on the touch screen is translated into pixels on the screen. The software takes X, Y, and Z readings, which are shown at the top of this box. As the touch pressure is increased, the pixel size increases; a lighter touch results in smaller pixel sizes.
Program Description Figure 3-2. Configuration Screen 3.4.2.1 ADC Control Section This section controls all the parameters of the A/D converter. Each slider controls one parameter, whose value is shown next to the slider. Each slider is described below. - Resolution Selects between 8-, 10-, and 12-bit resolution. - Conversion Clock The internal clock which runs the A/D converter can run at 8, 4, 2, or 1 MHz.
Program Description - Averaging Several readings may be taken and then averaged to give a single result. No averaging can be chosen, or 4, 8, or 16 readings can be averaged. Note that these settings apply to all operations of the A/D converter, not just the touch screen operations. Thus, resolution and averaging can be changed to increase accuracy in the data acquisition functions. 3.4.2.
Program Description is set by using the slider in this section. Note that sliders, when selected, can change value by either moving the mouse or using the arrow keys on the PC keyboard. Note that the DAC output voltage is dependent upon the resistor network and pullup voltage used on the hardware. Refer to the TSC2301 data sheet for more information on the DAC operation. 3.4.3 Data Acquisition Screen The data acquisition functions of the TSC2301 can be accessed on this screen, shown in Figure 3-4.
Program Description Figure 3-5. Audio Screen 3.4.4.1 ADC Section Checking the Power Up This Section checkbox can enable the audio ADC. This enables the other controls in this section of the screen. Checking the Stereo Volume box ties the left and right channels of the volume control together, so they can be moved as one. When in stereo volume mode, checking either channel’s Mute checkbox mutes both channels.
Program Description Figure 3-6. Microphone Input Selected The microphone gain may be set to 0 dB, 6 dB, or 12 dB. A microphone bias voltage can also be generated by the TSC2301; checking the Mic Bias On checkbox enables this feature. Note that to use this feature, JMP4 must be set to positions 2-3. 3.4.4.2 DAC Section Like the ADC section, the TSC2301 audio DAC can be powered on or off. Volume controls work the same as in the ADC section. Two digital filters are provided by the TSC2301 for the audio DAC.
Program Description The TSC2301’s mono output can take as its source either the left channel ADC input signal, or a mono mix of the TSC2301 audio output. The source is selectable when the mono output is enabled. 3.4.5 Bass Boost Filter Screen The Bass Boost Filter screen displays all of the coefficients for the bass boost filter function of the TSC2301. Since these are programmable, other functions may be programmed, not just bass boost. This screen is shown in Figure 3-7. Figure 3-7.
Chapter 4 Physical Description This chapter contains the component locations, bill of materials, and the schematics. Topic Page 4.1 Component Locations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2 4.2 Bill of Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3 4.3 Schematics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Component Locations 4.
Bill of Materials 4.
Bill of Materials Qty Reference Designators Manufacturer Mfr Part number Description 4 R27, R28, R29, R42 Panasonic or alternate ERJ-6ENF3091V RES 3.09 kΩ 1/10W 1% 0805 SMD 4 R11, R12, R13, R14 Panasonic or alternate ERJ-6GEYJ512V RES 5.
Schematics 4.3 Schematics Schematic diagrams of the TSC2301EVM showing the TSC2301 connections and the USB and connectors are shown on the following pages.
1 2 3 4 5 6 Revision History REV ECN Number Approved I2SDOUT I2SDIN JMP2 2 1 LRCLK C12 BCLK R13 5.1K 1uF MCLK D C17 220pF +3.3V R11 5.1K J3 D JMP3 X+ R14 29 15 62 54 VDDHP AVDD 23 24 25 26 27 MCLK BCLK LRCLK I2SDIN I2SDOUT 22 COO COI R12 5.
1 2 3 4 5 6 REVISION HISTORY REV ENGINEERING CHANGE NUMBER APPROVED J12 1 2 D D J7 USB SLAVE CONN TP7 3 BCLK +3.3V SCL SDA 1 2 3 24LC64I/SN 1 3 5 7 9 C35 33pF C34 33pF R35 1 2 3 4 2 4 6 8 10 X- 0 J13 J10 WP VSS LRCLK 7 4 VCC A0 A1 A2 1 2 3 4 C30 1uF R34 I2SDOUT U3 8 TERMBLOCK-4 I2SDIN 6 +3.3V 4 MCLK R28 3.09K R27 3.09K 5 VCC DD+ GND TP8 Y+ 0 R36 X+ 0 TOUCH SCREEN R37 AUDIO DATA Y- 0 X1 100pF C33 R29 .001uF 3.09K C41 .1uF C42 .
