EP9312-CBZ Cirrus Logic Inc, EP9312-CBZ Datasheet - Page 753

• Manufacturer Part Number: EP9312-CBZ
• Description: IC ARM9 SOC UNIVERSAL 352PBGA
• Manufacturer: Cirrus Logic Inc
• Series: EP9r

Specifications of EP9312-CBZ

• Core Size: 16/32-Bit
• Core Processor: ARM9
• Speed: 200MHz
• Connectivity: EBI/EMI, EIDE, Ethernet, I²C, IrDA, Keypad/Touchscreen, SPI, UART/USART, USB
• Peripherals: AC'97, DMA, I&sup2:S, LCD, LED, MaverickKey, POR, PWM, WDT
• Number Of I /o: 16
• Program Memory Type: ROMless
• Ram Size: 32K x 8
• Voltage - Supply (vcc/vdd): 1.65 V ~ 3.6 V
• Data Converters: A/D 8x12b
• Oscillator Type: External
• Operating Temperature: 0°C ~ 70°C
• Package / Case: 352-BGA
• Controller Family/series: (ARM9)
• No. Of I/o's: 16
• Ram Memory Size: 16MB
• Cpu Speed: 200MHz
• No. Of Timers: 4
• No. Of Pwm Channels: 2
• Digital Ic Case Style: BGA
• Embedded Interface Type: AC97, I2S, SPI, UART, USB
• Rohs Compliant: Yes
• Processor Series: EP93xx
• Core: ARM920T
• Data Bus Width: 32 bit
• 3rd Party Development Tools: MDK-ARM, RL-ARM, ULINK2
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Program Memory Size: -
• Lead Free Status / Rohs Status: Details
• Other names: 598-1258

DS785UM1
25.2.5 Measuring Touch Screen Resistance
The analog switch array can be configured to get an approximation of touch screen
resistance. This may be useful for advanced touch screen algorithms that either try to
determine how hard a touch screen is being pressed, or if it is being pressed in more than
one location. The touch screen controller built-in algorithm does not use this feature. More
advanced algorithms would need to perform either primary or additional scanning through the
APB interface. Please note that the initial A / D converter read should be viewed as a convert
command where the data provided is stale and should be discarded.
The register values for TSDirect can be derived from the switch positions in the diagram. A
“1” in the register bit position indicates that the switch is made or closed. Therefore, the
TSDirect value for 4- or 8-wire X-axis resistance measurement should be set to
0x0040_1601, the TSDirect value for 4- or 8-wire Y-axis resistance measurement should be
set to 0x0080_4604, and the TSDirect value for 5-wire resistance measurement should be
set to 0x0080_4604. See
X+
Y+
X-
Y-
4/8 wire Measure X-AXIS
100K
100K
Resistance
SW22
SW23
SW19
SW11
SW20
SW13
SW21
SW12
SW14
SW24
SW25
SW26
SW27
SW15
SW16
SW17
SW18
SW0
SW1
SW2
SW3
SW4
SW5
SW6
SW7
VDD
SW10
SW9
A/D CONVERTER
REF-
REF+
IN
Figure 25-9. Measure Resistance Switching Diagram
Figure
X+
Y+
X-
Y-
Copyright 2007 Cirrus Logic
4/8 wire Measure Y-AXIS
25-9.
100K
100K
Resistance
SW22
SW23
SW19
SW11
SW20
SW13
SW21
SW12
SW14
SW24
SW25
SW26
SW27
SW15
SW16
SW17
SW18
SW0
SW1
SW2
SW3
SW4
SW5
SW6
SW7
VDD
SW10
SW9
A/D CONVERTER
REF+
REF-
IN
Not used
Not used
Not used
Wiper
Z+/-
Z-/+
V+
V-
5 wire Measure Corner to
Corner Resistance
Analog Touch Screen Interface
100K
100K
SW22
SW23
SW19
SW11
SW20
SW13
SW21
SW12
SW14
SW24
SW25
SW26
SW27
SW15
SW16
SW17
SW18
SW0
SW1
SW2
SW3
SW4
SW5
SW6
SW7
EP93xx User’s Guide
VDD
SW10
SW9
A/D CONVERTER
REF+
REF-
IN
25-15
25