LCD Controller

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Issue date: 13 August, 1999

Syntek Semiconductor Co., Ltd.

STK55C324

4 : = 0 CPU clock is system clock.

= 1 CPU clock is 32.768K Hz.

7-5 : Reserved.

The default values for each bit is zero.

1003 IRQ flag register. Read & write.

Read function :

Bit 0 : = 1 Fix-time timer interrupt, IRQ1.

1 : = 1 Timer interrupt, IRQ2.

2 : = 1 External interrupt, IRQ3.

Write function :

Bit 0 : = 0 Clear fix-time timer interrupt.

1 : = 0 Clear timer interrupt.

2 : = 0 Clear external interrupt.

* Before firmware exits the interrupt routine, the interrupt flag must be cleared. Otherwise, the IC will

get into interrupt again.

* Write 0 to clear the corresponding IRQ but do not use ‘STZ

$1003’ to clear all interrupts at the

same time. Following instructions are recommended

LDA

$1003

STA

IRQBuff

EOR

#0FFH

STA

$1003

;Clear all active interrupts at the same time

LDA

IRQBuff

AND

#1

BEQ

next_irq

* Do NOT use TRB to test and clear this register. Following instructions are recommended.

LDA

$1003

AND

#1

;Check IRQ 1

BEQ

next_irq

STA

$1003

;Clear the active interrupt.

1004 Port 1 data. Read & write.

1005 Set port 1 bit function. Write only.

* An '1' in this register will set the corresponding pin of port 1 as an output pin.

* The default values for each bit is zero. A pull-up resistor can be added to the pin by code option.