1998 Jul 30

11

Philips Semiconductors

Product specification

LCD controller/driver

PCF2105

Fig.6 Relationship between CGRAM addresses, data and display patterns.

Character code bits 0 to 3 correspond to CGRAM address bits 3 to 6.

CGRAM address bits 0 to 2 designate character pattern line position. The 8th line is the cursor position and display is performed by logical OR with the

cursor. Data in the 8th line will appear in the cursor position.

Character pattern column positions correspond to CGRAM data bits 0 to 4; bit 4 being at the left end, as shown in this figure.

CGRAM character patterns are selected when character code bits 4 to 7 are all logic 0. CGRAM data is logic 1 corresponds to selection for display.

Only bits 0 to 5 of the CGRAM address are set by the ‘set CGRAM address’ instruction. Bit 6 can be set using the ‘set DDRAM address’ instruction or

by using the auto-increment feature during CGRAM write. All bits 0 to 6 can be read using the ‘read busy flag and address’ instruction.

handbook, full pagewidth

MGA800 - 1

7

654

321

0

654

321

0

432

10

higher

order

bits

lower

order

bits

lower

order

bits

higher

order

bits

lower

order

bits

higher

order

bits

0

000

000

0

0

000

000

0

001

00

0

010

00

0

011

0

100

0

0

0

101

00

0

110

00

0

111

000

00

000

00

0

001

0

0

0

010

00

00

011

100

101

00

00

110

00

00

111

000

00

001

0

000

000

1

0

001

0

000

001

0

0

000

111

1

0

000

111

1

0

000

111

1

0

000

111

1

01

0

0

000

100

101

110

1

1

1

1

1

1

1

1

1

1

1

1

1

1

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1

11

1

character codes

(DDRAM data)

CGRAM

address

character patterns

(CGRAM data)

character

pattern

example 1

cursor

position

character

pattern

example 2