EPSON Research and Development

Page 13

Vancouver Design Center

 

 

 

4.2.2 Standard Epson LCD Connector, J4

A shrouded 40-pin header, J4, is also added to the CPU module to connect to LCD panels. This header is the standard LCD connector used on Epson Research and Development evaluation boards and can be used to directly connect LCD panels to the S1D13704/5 controller. All LCD signals are buffered to allow 3.3V or 5.0V logic LCD panels to be connected. Jumper, JP9, selects between these two types of panels.

A positive power supply for panels requiring a positive bias voltage is supplied to header J4, by the LCD module through the 50-pin LCD module connector, J3. No negative power supply is available on the LCD module, therefore only panels which have their own bias voltage supply, or those that use a positive supply, can be connected to J4. The LCD module can only support these panels as well.

Header, J4, and its associated buffers and components have been left unpopulated on the CPU module. These parts can be added by the user if desired.

4.3 LCD Controller

4.3.1 S1D13704 vs. S1D13705

The LCD controller used in conjunction with the TMPR3912/22U microprocessor can either be a S1D13704 or a S1D13705. If a S1D13704 is used, jumper JP7 must be set to position 1 2. This setting allows CNF4 to be configured for the S1D13704. CNF4 controls the polarity of the LCDPWR signal and can be set either high or low with jumper, JP11. If a S1D13705 is used, jumper JP7 must be set to position 2 3. This setting allows pin 45 of the LCDC to be used as address bit, AB16, which is needed on the S1D13705 to accom- modate the larger display memory.

4.3.2 LCDPWR Polarity

The power supply on the LCD module used LCDON, an active low signal to turn on the supply. This signal is connected to LCDPWR. Since LCDPWR is configurable on the S1D13704 and is set active high on the S1D13705, a facility must be provided to invert this signal if it is active high so that LCDON will be the right polarity to turn on the LCD power supply. Jumper, JP10 must be set to position 1 2 if LCDPWR is active low and to position 2 3 if LCDPWR is active high.

4.3.3 S1D13704\75 Chip Select

Minimal glue logic is used on the CPU module to provide the chip select signal, CS#, for the LCDC. A simple AND gate activates the S1D13704/5 whenever the PC Card slot #1 is accessed, whether it be memory space or attribute space.

S5U13704/5 - TMPR3912/22U CPU Module

 

Issue Date: 01/03/07

X00A-G-004-02

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Image 527
Epson technical manual Standard Epson LCD Connector, J4, LCD Controller 1 S1D13704 vs. S1D13705, Lcdpwr Polarity