hd66765 Renesas Electronics Corporation., hd66765 Datasheet - Page 29

• Manufacturer Part Number: hd66765
• Description: 396-channel Segment Driver With Internal Ram For 4096-color Displays - Hitachi Semiconductor
• Manufacturer: Renesas Electronics Corporation.

RAM Write Data Mask (R20h)
WM11–0: In writing to the GRAM, these bits mask writing in a bit unit. When WM11 = 1, this bit
masks the write data of DB11 and does not write to the GRAM. Similarly, the WM10–0 bits mask the
write data of DB10–0 in a bit unit. When SWP = 1, the upper and lower bytes in the write data mask are
swapped. For details, see the Graphics Operation Function section.
RAM Address Set (R21h)
AD15–0: Initially set GRAM addresses to the address counter (AC). Once the GRAM data is written,
the AC is automatically updated according to the AM and I/D bit settings. This allows consecutive
accesses without resetting addresses. Once the GRAM data is read, the AC is not automatically updated.
GRAM address setting is not allowed in the standby mode. Ensure that the address is set within the
specified window address.
Table 13
AD14–AD0
"0000"H–"0083"H
"0100"H–"0183"H
"0200"H–"0283"H
"0300"H–"0383"H
"AC00"H–"AC83"H
"AD00"H–"AD83"H
"AE00"H–"AE83"H
"AF00"H–"AF83"H
R/W
R/W
W
W
RS
RS
1
1
:
GRAM Address Range in Eight-grayscale Mode
DB15
DB15
AD
15
0
DB14
DB14
AD
14
0
DB13
DB13
AD
13
0
Figure 19 RAM Write Data Mask Instruction
GRAM Setting
Bitmap data for COM1
Bitmap data for COM2
Bitmap data for COM3
Bitmap data for COM4
Bitmap data for COM173
Bitmap data for COM174
Bitmap data for COM175
Bitmap data for COM176
Figure 20 RAM Address Set Instruction
DB12
DB12
AD
12
0
DB11
WM
DB11
AD
11
11
:
DB10
WM
DB10
AD
10
10
WM
DB9
DB9
AD
9
9
29
WM
DB8
DB8
AD
8
8
WM
DB7
DB7
AD
7
7
WM
DB6
DB6
AD
6
6
WM
DB5
DB5
AD
5
5
WM
DB4
DB4
AD
4
4
WM
DB3
DB3
AD
3
3
WM
DB2
DB2
AD
2
2
HD66765
WM
DB1
DB1
AD
1
1
WM
DB0
DB0
AD
0
0