LCD Controller

4 /24

Issue date: 13 August, 1999

Syntek Semiconductor Co., Ltd.

STK55C324

The middle bits are in the order.

0040-00DF for zero page area.

0100-01DF for stacks. This area is overlapped with 0000-00DF.

2) ROM

8000-FFFF for program area.

FFFF, FFFE - IRQ vector.

FFFD, FFFC - RES vector.

FFFB, FFFA - NMI vector.

3) Others

1000 To enter stand-by mode. Write only.

* Write this address, the CPU will be hold with LCD state no change.

* When in stand-by mode, the NMI and IRQ will wake up the CPU.

1001 To enter sleep mode. Write only.

Bit 0 = 1 Sleep mode 1

1 = 1 Sleep mode 2

In sleep mode 1, both of the main system oscillator and 32.768KHz sub-system oscillator will be

stopped. So, all functions are stopped and only external interrupt can wake up this chip. The LCD

display will be turn off while getting into sleep mode 1. If the LCD is turned on after wake-up

immediately, then some garbage may display on the LCD. It is better to turn off the LCD by software

before enter sleep mode 1. After wake up, the software has to delay several ms before turn on the

LCD because the crystal will take several mS to stable.

In sleep mode 2, only main system oscillator will be stopped. So, the following functions will still keep

working.

* The LCD will be kept on.

* The fix-time timer will keep going.

* The NMI, port 1, and fix-time timer interrupt will wake up this chip.

* CPU will keep working if clock source is 32.768K Hz.

1002 Watch timer control register. Write only.

Bit 1 : = 0 Set fix-time timer interrupt at 2 Hz

= 1 Set fix-time timer interrupt at 1 Hz