TWR-LCD Freescale Semiconductor, TWR-LCD Datasheet - Page 6

• Manufacturer Part Number: TWR-LCD
• Description: LCD MODULE FOR TWR SYSTEM
• Manufacturer: Freescale Semiconductor

Specifications of TWR-LCD

• Accessory Type: LCD Display
• Product: Microcontroller Modules
• Data Bus Width: 32 bit
• Core Processor: MCF51JM
• Interface Type: USB, I2C, SPI
• Operating Supply Voltage: 5 V
• Silicon Manufacturer: Freescale
• Core Architecture: Coldfire
• Core Sub-architecture: Coldfire V1
• Silicon Core Number: MCF51
• Silicon Family Name: Flexis - MCF51AC, MCF521x, MCF5301x
• Rohs Compliant: Yes
• For Use With/related Products: Freescale Tower System
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

If utilizing a Tower MCU module to drive the SPI to the LCD display controller, use SW1‐DIP5 to specify
the desired SPI chip select.
3.2.3 Resistive Touch Overlay
The TWR‐LCD display features an integrated analog resistive touch panel. The panel can be access by
either the on‐board MCF51JM MCU or a compatible Tower MCU module. The selection of which MCU
interfaces the Touch Panel is independent of which MCU is driving the LCD display controller
(designated by JM/ELE).
Use SW1‐DIP6 to specify which MCU has access to the resistive touch panel. Refer to Section 4 for
more configuration details.
Setting the TP SEL (SW1‐DIP6) configuration switch to the “Off” position will indicate to the on‐board
MCF51JM MCU that it is the interfacing MCU to the touch panel’s analog signals.
Setting the TP SEL configuration switch to the “On” position will indicate to the on‐board MCF51JM
MCU that the tower MCU Module is the interfacing MCU to the touch panel’s analog signals. It is
required that on‐board MCF51JM MCU firmware detect the status of the To SEL signal and tri‐state the
respective on‐board MCF51JM MCU ADC signals.
SW5 is used to isolate the touch panel’s analog signals from the Tower Elevator Side Expansion Port.
This ensures correct isolation of the analog signals when the on‐board MCF51JM MCU is used. SW5‐
DIP[4:1] should all be set to the “Off” position if the on‐board MCF51JM MCU is being used to interface
the resistive touch panel.
SW5-DIP 1
SW5-DIP 2
SW5-DIP 3
(SW1-DIP5)
(SW1-DIP6)
SPI CS SEL
TP SEL
Touch Panel
Isolation (XPLS)
Touch Panel
Isolation (XMNS)
Touch Panel
OFF
OFF
ON
ON
Table 5 ‐ Resistive Touch Analog Isolation Settings
Table 4 ‐ Resistive Touch MCU Selection
Table 3 ‐ Tower MCU SPI CS Selection
Select SPI0 CS1 as the chip-select for LCD SPI interface
Select SPI0 CS0 as the chip-select for LCD SPI interface
Disables MCF51JM connection to the LCD Touch Panel
Enables MCF51JM connection to the LCD Touch Panel
Use SW5 to enable ADC connection from Primary Elevator Connector
Ensure that all switches on SW5 DIP are OFF
OFF
OFF
ON
ON
ON
TWR‐LCD User’s Manual
Connects AN4 (TWR-ELEV) to XPLS Touch Panel Signal
Connects AN5 (TWR-ELEV) to XMNS Touch Panel Signal
Connects AN6 (TWR-ELEV) to YMNS Touch Panel Signal
Disconnects AN4 from Touch Panel
Disconnects AN5 from Touch Panel
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