ST2601B

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Step1: use the macro “SWITCH_SYSCLK_32K_TO_RC ”to change Sysclk to RC

(7) sample code

1. When B/W, 4G, 16G mode change to fast B/W mode or fast B/W mode change to B/W, 4G, 16G mode, must turn off LCD.

for example: B/W, 4G, 16G mode change to fast B/W mode.

;====Step1 LCD OFF ===

LDA LCTR

ORA #10000000B

STA

LCTR

;====Step2 set GL[3:2]=11, fast B/W mode ===

LDA LCTR

ORA #00001100B

STA

LCTR

;=== Step3 set Frame rate about 65 Hz ===

LDA #6

;when Sysclk is changed to 32k, LFRA can’tbe modified. Thus LFRA

STA

LFRA

;is determined by equation2. Let the frame rate in sysclk=32k mode is

;about 65hz

LDA #00001000B

;since LFRA has been determined, LCKR is determined by frame rate equation.

STA

LCKR

;Let the frame rate in Sysclk=RC mode is about 65hz

;===Step4 LCD ON ===

LDA LCTR

AND #~10000000B

STA

LCTR

[After setting up fast B/W mode, then switch SYSCK from RC to 32k]

2. Sysck from RC change to 32k…

Please use the macro “SWITCH_SYSCLK_RC_TO_32K”.

This macro will use 4 bytes RAM. They are show below.

;===== used ram ====

LCD_FLAG

DS

1

IENAL_BAK

DS

1

IENAH_BAK

DS

1

LPCK_BAK

DS 1

And this macro will also use LCD interrupt. Please copy below program in LCD interrupt service routine.

;==== LCD interrupt service routine ===

LCDFR_ISR:

PHA

LDA #FFH

STA

LCD_FLAG

RMB7

IENAL

;DISABPLE LCD INTERRUPT

PLA

RTI

The declaration of this macro is show below (please don’tmodify this macro)

SWITCH_SYSCLK_RC_TO_32K

.MACRO

;=== backup LPCK ===

LDA LPCK

STA

LPCK_BAK

LDA #2

STA

LPCK

;=== BACKUP IENAL/H AND ONLY ENABLE LCD INT ===

SEI

LDA IENAL

STA

IENAL_BAK

LDA IENAH

STA

IENAH_BAK

LDA #10000000B

;ONLY ENABLE LCD INT

STA

IENAL

STZ

IENAH

LDA #01111111B