hd66108 Renesas Electronics Corporation., hd66108 Datasheet - Page 14

• Manufacturer Part Number: hd66108
• Description: Ram-provided 165-channel Lcd Driver For Liquid Crystal Dot Matrix Graphics - Hitachi Semiconductor
• Manufacturer: Renesas Electronics Corporation.

2. Display Memory Construction and Word Length Setting
The HD66108T has a bit-mapped display memory of 165
MPU is stored in the display memory, with the MSB (most significant bit) on the left and the LSB (least
significant bit) on the right.
The sections on the LCD panel corresponding to the display memory bits in which 1’s are written will be
displayed as on (black).
Display area size of the internal RAM is determined by control register (FCR) settings (refer to Table 1).
The start address in the Y direction for the display area is always Y0, independent of the register setting.
In contrast, the start address in the X direction is X0 in the modes for 165-column-output, 65-row-output
from the right side, and 33-row-output from the right side, and is X32 in the 65-row-output mode from
the left and right sides.
Each display area contains the number of dots shown in Table 1, beginning from each start address.
For more detail, refer to “4.2 Row Output Data Setting,” Figures 15 to 19.
In the display memory, one X address is assigned to each word of 8 or 6 bits long in X direction. (Either
8 or 6 bits can be selected as word length of display data.) Similarly, one Y address is assigned to each
row in Y direction.
Accordingly, X address 20 in the case of 8-bit word and X address 27 in the case of 6-bit word have 5 and
3 bits of display data, respectively. Nevertheless, data is also stored here with the MSB on the left (Figure
5).
Figure 4 Relationship between Memory Construction and Display
COM65
COM1
COM2
Y64
Y0
(MSB)
X0 X1 X2 X3 X4 X5 X6 X7
1
DB7
Display on
0
1
0
0
1
0
165
(LSB)
DB0
display memory
1
156
65-dot LCD
65-bit
65 bits. As shown in Figure 4, data from the
X164
HD66108
967