FEDL9209-01

LAPIS Semiconductor

ML9209-xx

13/29

Description of Commands and Functions

1. “DCRAM data write” command

(Specifies the address of DCRAM and writes the character code of CGROM and CGRAM.)

DCRAM (Data Control RAM) has a 4-bit address to store character codes of CGROM and CGRAM.

A character code specified by DCRAM is converted to an alphanumeric character pattern via CGROM or

CGRAM.

The DCRAM can store 16 characters worth of character codes.

[Command format]

X0 X1 X2 X3

1

0

0

0

B0 B1 B2 B3 B4 B5 B6 B7

1st byte

(1st)

LSB

MSB

C0 C1 C2 C3 C4 C5 C6 C7

B0 B1 B2 B3 B4 B5 B6 B7

2nd byte

(2nd)

LSB

MSB

: Setup and DCRAM address in the write mode

of DCRAM data are specified.

(Example: Specify DCRAM address 0H.)

: Specify character code of CGROM and CGRAM.

(It is written into DCRAM address 00H.)

To specify the character code of CGROM and CGRAM to the next address continuously, specify only character

code as follows.

Since the address of DCRAM is automatically incremented, address specification is unnecessary.

C0 C1 C2 C3 C4 C5 C6 C7

B0 B1 B2 B3 B4 B5 B6 B7

2nd byte

(3rd)

LSB

MSB

C0 C1 C2 C3 C4 C5 C6 C7

B0 B1 B2 B3 B4 B5 B6 B7

2nd byte

(4th)

LSB

MSB

: Specify character code of CGROM and CGRAM.

(It is written into DCRAM address 1H.)

: Specify character code of CGROM and CGRAM.

(It is written into DCRAM address 2H.)

B0 B1 B2 B3 B4 B5 B6 B7

2nd byte

(17th)

LSB

MSB

C0 C1 C2 C3 C4 C5 C6 C7

B0 B1 B2 B3 B4 B5 B6 B7

2nd byte

(18th)

LSB

MSB

: Specify character code of CGROM and CGRAM.

(It is written into DCRAM address FH.)

: Specify character code of CGROM and CGRAM.

(It is rewritten into DCRAM address 0H.)

C0 C1 C2 C3 C4 C5 C6 C7

X0 (LSB) to X3 (MSB): DCRAM address (4 bits: 16 characters worth)

C0 (LSB) to C7 (MSB): Character code of CGROM and CGRAM (8 bits: 256 characters worth)