5

* This specification are subject to be changed without notice.

EM73963A

4-BIT MICRO-CONTROLLER FOR LCD PRODUCT

6.14.2001

B

XA2

:

; - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

BANK 2

XB1 :

:

:

BXB

:

XB2 :

:

B

XB2

:

; - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

BANK 3

XC1 :

:

:

BXC

:

XC2 :

:

B

XC2

Fixed data can be read out by table-look-up instruction. Table-look-up instruction requires the Data point

(DP) to indicate the ROM address in obtaining the ROM code data (Except bank 0) :

LDAX

Acc ←

←

←

←

← ROM[DP]

L

LDAXI

Acc ←

←

←

←

← ROM[DP]

DP is a 12-bit data register that stores the program ROM address as pointer for the ROM code data.

User has to initially load ROM address into DP with instructions "STADPL", and "STADPM, STADPH",

then to obtain the lower nibble of ROM code data by instruction "LDAX" and higher nibble by instruction

"LDAXI"

PROGRAM EXAMPLE: Read out the ROM code of address 1777h by table-look-up instruction.

LDIA #07h;

STADPL

; [DP]

STADPM ; [DP]

STADPH

; [DP]

:

OUT #00H , P3 ; Set in bank 1

LDL #00h;

LDH #03h;

LDAX

; ACC ← 6h

STAMI

; RAM[30] ← 6h

LDAXI

; ACC ← 5h

STAM

; RAM[31] ← 5h

;

ORG 1777h

DATA 56h;

DATA RAM (372-nibble )

A total 372 - nibble data RAM is available from address 000 to 17Fh

Data RAM includes the zero page region, stacks and data area.